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Łastowska O, Starosta R, Jabłońska M, Kubit A. Exploring the Potential Application of an Innovative Post-Weld Finishing Method in Butt-Welded Joints of Stainless Steels and Aluminum Alloys. Materials (Basel) 2024; 17:1780. [PMID: 38673137 PMCID: PMC11051480 DOI: 10.3390/ma17081780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 03/29/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024]
Abstract
The prerequisite of the weld bead finishing is intricately linked to the quality of the welded joint. It constitutes the final, yet pivotal, stage in its formation, significantly influencing the reliability of structural components and machines. This article delineates an innovative post-weld surface finishing method, distinguished by the movement of a specialized cutting tool along a butt weld. This method stands out due to its singular approach to machining allowance, wherein the weld bead height is considered and eradicated in a single pass of the cutting tool. Test samples were made of AISI 304L, AISI 316L stainless steels and EN AW-5058 H321, EN AW-7075 T651 aluminum alloys butt-welded with TIG methods. Following the welding process, the weld bead was finished in accordance with the innovative method to flush the bead and the base metal's surface. For the quality control of welded joints before and after the weld finishing, two non-destructive testing methods were chosen: Penetrant Testing (PT) and Radiographic Testing (RT). This article provides results from the examination of 2D profile parameters and 3D stereometric characteristics of surface roughness using the optical method. Additionally, metallographic results are presented to assess changes in the microstructure, the microhardness, and the degree of hardening within the surface layer induced by the application of the innovative post-weld finishing method.
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Affiliation(s)
- Olga Łastowska
- Department of Engineering Sciences, Faculty of Marine Engineering, Gdynia Maritime University, 81-87 Morska St., 81-225 Gdynia, Poland;
| | - Robert Starosta
- Department of Engineering Sciences, Faculty of Marine Engineering, Gdynia Maritime University, 81-87 Morska St., 81-225 Gdynia, Poland;
| | - Monika Jabłońska
- Faculty of Mechanical and Electrical Engineering, Polish Naval Academy, 69 Jana Smidowicza Str., 81-127 Gdynia, Poland;
| | - Andrzej Kubit
- Department of Manufacturing and Production Engineering, Rzeszow University of Technology, al. Powst. Warszawy 8, 35-959 Rzeszow, Poland;
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Baruwa AO, Chasqueira F, Arantes-Oliveira S, Caramês J, Marques D, Portugal J, Martins JNR. Comparative Analysis of Endodontic ISO Size 06, 08, and 10 Stainless Steel K-Files Used for Glide Path Procedures. Dent J (Basel) 2024; 12:98. [PMID: 38668010 PMCID: PMC11048936 DOI: 10.3390/dj12040098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/21/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Small-sized stainless steel hand files are conventionally employed in root canal treatment procedures for canal scouting and for glide path establishment, owing to their superior flexibility and proficiency in navigating confined spaces. Given the diversity of brands available in the market, there exists potential variability in their physical characteristics, thereby influencing clinical performance. Consequently, this study aims to conduct a comparative analysis of the design, metallurgy, and mechanical characteristics among seven stainless steel hand file brands across ISO sizes 06, 08, and 10. A total of 315 new 25 mm length stainless steel hand files with apical sizes of 0.06, 0.08, and 0.10 from seven distinct brands were included in the study. A meticulous inspection of all instruments was undertaken to identify any structural deformations that might render them ineligible for the study. The design inspection involved the random selection of instruments from each group, which were examined under various microscopes, including a dental operating microscope, optical microscope, and scanning electron microscope. Furthermore, two instruments from each group underwent energy-dispersive X-ray spectroscopy analysis for elemental composition documentation. Mechanical tests were conducted to evaluate the instruments' resistance to lateral deformation (buckling) and their microhardness. Statistical analysis was executed using the nonparametric Mood's median test, with a predetermined significance level of 0.05. Regarding the instruments design, all files exhibited an active blade length ranging from 16 to 17 mm. However, variations were observed in the number of spirals, tip designs, and sizes, with the API K-File notably larger in sizes 0.06 and 0.08 compared to the other instruments. Despite uniform elements composition, differences in geometric features and mechanical properties were evident. Concerning buckling strength, the API K-File demonstrated superior performance across all tested sizes, while the Dentsply ReadySteel, SybronEndo, and Mani K-Files exhibited lower results (p < 0.05). In microhardness assessments, both the API and Oro K-Files displayed the lowest outcomes, with medians of 531 HVN and 532 HVN, respectively, whereas the SybronEndo K-File exhibited the highest microhardness (657 HVN). Despite similar metallurgical composition, the observed distinctions in geometric features and mechanical properties underscore the impact of the manufacturing process on the characteristics of glide path stainless steel endodontic files. These disparities may ultimately influence their clinical performance.
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Affiliation(s)
- Abayomi Omokeji Baruwa
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal; (A.O.B.); (S.A.-O.); (J.C.); (D.M.); (J.P.)
| | - Filipa Chasqueira
- Instituto Universitário Egas Moniz, 2829-511 Monte da Caparica, Portugal;
| | - Sofia Arantes-Oliveira
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal; (A.O.B.); (S.A.-O.); (J.C.); (D.M.); (J.P.)
- Grupo de Investigação em Materiais Dentários (BIOMAT), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), 1600-277 Lisboa, Portugal
- LIBPhys-FCT UID/FIS/04559/2013 (https://doi.org/10.54499/UIDB/04559/2020), 1600-277 Lisboa, Portugal
| | - João Caramês
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal; (A.O.B.); (S.A.-O.); (J.C.); (D.M.); (J.P.)
- LIBPhys-FCT UID/FIS/04559/2013 (https://doi.org/10.54499/UIDB/04559/2020), 1600-277 Lisboa, Portugal
- Instituto de Implantologia, 1070-064 Lisboa, Portugal
| | - Duarte Marques
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal; (A.O.B.); (S.A.-O.); (J.C.); (D.M.); (J.P.)
- LIBPhys-FCT UID/FIS/04559/2013 (https://doi.org/10.54499/UIDB/04559/2020), 1600-277 Lisboa, Portugal
- Instituto de Implantologia, 1070-064 Lisboa, Portugal
- Grupo de Investigação em Bioquimica e Biologia Oral (GIBBO), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), 1600-277 Lisboa, Portugal
- Centro de Estudos de Medicina Dentária Baseada na Evidência (CEMDBE), 1600-277 Lisboa, Portugal
| | - Jaime Portugal
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal; (A.O.B.); (S.A.-O.); (J.C.); (D.M.); (J.P.)
- Grupo de Investigação em Materiais Dentários (BIOMAT), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), 1600-277 Lisboa, Portugal
| | - Jorge N. R. Martins
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal; (A.O.B.); (S.A.-O.); (J.C.); (D.M.); (J.P.)
- LIBPhys-FCT UID/FIS/04559/2013 (https://doi.org/10.54499/UIDB/04559/2020), 1600-277 Lisboa, Portugal
- Instituto de Implantologia, 1070-064 Lisboa, Portugal
- Grupo de Investigação em Bioquimica e Biologia Oral (GIBBO), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), 1600-277 Lisboa, Portugal
- Centro de Estudos de Medicina Dentária Baseada na Evidência (CEMDBE), 1600-277 Lisboa, Portugal
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Hsu HC, Wu SC, Fang WC, Ho WF. Experimental Investigation of the Impact of Niobium Additions on the Structural Characteristics and Properties of Ti-5Cr-xNb Alloys for Biomedical Applications. Materials (Basel) 2024; 17:1667. [PMID: 38612179 PMCID: PMC11012571 DOI: 10.3390/ma17071667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/02/2024] [Accepted: 04/03/2024] [Indexed: 04/14/2024]
Abstract
In this study, a series of Ti-5Cr-xNb alloys with varying Nb content (ranging from 1 to 40 wt.%) were investigated to assess their suitability as implant materials. Comprehensive analyses were conducted, including phase analysis, microscopy examination, mechanical testing, and corrosion resistance evaluation. The results revealed significant structural alterations attributed to Nb addition, notably suppressing the formation of the ω phase and transitioning from α' + β + ω to single β phase structures. Moreover, the incorporation of Nb markedly improved the alloys' plastic deformation ability and reduced their elastic modulus. In particular, the Ti-5Cr-25Nb alloy demonstrated high values in corrosion potential and polarization resistance, signifying exceptional corrosion resistance. This alloy also displayed high bending strength (approximately 1500 MPa), a low elastic modulus (approximately 80 GPa), and outstanding elastic recovery and plastic deformation capabilities. These aggregate outcomes indicate the promising potential of the β-phase Ti-5Cr-25Nb alloy for applications in orthopedic and dental implants.
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Affiliation(s)
- Hsueh-Chuan Hsu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 406053, Taiwan; (H.-C.H.); (S.-C.W.)
| | - Shih-Ching Wu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 406053, Taiwan; (H.-C.H.); (S.-C.W.)
| | - Wei-Ching Fang
- Department of Materials Science and Engineering, Da-Yeh University, Changhua 515006, Taiwan
| | - Wen-Fu Ho
- Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 811726, Taiwan
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Reidelbach C, Swoboda M, Spraul M, Vach K, Patzelt SBM, Hellwig E, Polydorou O. Effects of erosion and abrasion on resin-matrix ceramic CAD/CAM materials: An in vitro investigation. Eur J Oral Sci 2024; 132:e12967. [PMID: 38105518 DOI: 10.1111/eos.12967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 11/27/2023] [Indexed: 12/19/2023]
Abstract
The aim of the study was to evaluate the effects of erosion and abrasion on resin-matrix ceramic CAD/CAM materials [CERASMART (GC); VITA ENAMIC (VITA Zahnfabrik); Lava Ultimate (3 M)] in comparison to feldspar ceramic (VITABLOCS Mark II, VITA Zahnfabrik) and resin composite materials (ceram.x universal, Dentsply Sirona). Daily brushing and acid exposure were simulated using a brushing apparatus and a solution of 0.5 vol% citric acid. Microhardness, surface roughness, and substance loss were measured at baseline and after simulation of 1 and 3 years of function. All materials showed a decrease in microhardness after 3 years and an increase in surface roughness (Ra) after 1 and 3 years. The Ra increase was statistically significantly lower for the resin-matrix ceramics than for feldspar ceramic and similar to composite material. After 3 years, only feldspar ceramic showed no significant substance loss. In conclusion, resin-matrix ceramics demonstrate reduced roughening compared to feldspar ceramics, potentially improving restoration longevity by preventing plaque buildup, but differences in abrasion resistance suggest the need for further material-specific research. Future research should aim to replicate clinical conditions closely and to transition to in vivo trials.
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Affiliation(s)
- Cosima Reidelbach
- Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Michael Swoboda
- Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Mathias Spraul
- Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Kirstin Vach
- Institute for Medical Biometry and Statistics, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Sebastian B M Patzelt
- Praxis für Zahnmedizin, Zimmern ob Rottweil, Germany
- Department of Prosthetic Dentistry, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Elmar Hellwig
- Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Olga Polydorou
- Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
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Fidan M, Yağci Ö. Effect of aging and fiber-reinforcement on color stability, translucency, and microhardness of single-shade resin composites versus multi-shade resin composite. J ESTHET RESTOR DENT 2024; 36:632-642. [PMID: 37622399 DOI: 10.1111/jerd.13125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/23/2023] [Accepted: 08/07/2023] [Indexed: 08/26/2023]
Abstract
OBJECTIVE The purpose of this study was to evaluate the effect of aging and fiber-reinforcement on the color stability, translucency, and microhardness of single-shade resin composites versus multi-shade resin composite. MATERIALS AND METHODS Four resin composites (Filtek Z250, Omnichroma, Vittra APS Unique, Zenchroma) were tested. Three subgroups of specimens were prepared for each of the composites: control, polyethylene fiber-reinforcement, and glass fiber-reinforcement- groups (n = 10/per group). The samples were subjected to aging for 10,000 thermal cycles. Color differences (ΔE00 ) were calculated after aging. Relative translucency parameter (RTP00 ) and microhardness values were calculated before and after aging. A two-way analysis of variance and the generalized linear model was used (p < 0.05). RESULTS The lowest and highest ΔE00 values were found for Filtek Z250 (0.6 ± 0.2) and Omnichroma resin composites (1.6 ± 0.4), respectively. The ΔE00 value of the polyethylene fiber-reinforcement group (1.2 ± 0.6) was significantly higher than the ΔE00 value of the glass fiber-reinforcement group (1.0 ± 0.4, p < 0.001). The RTP00 value of the glass fiber-reinforcement group (1.92 ± 0.78) was significantly higher than the RTP00 value of the polyethylene fiber-reinforcement group (1.72 ± 0.77, p < 0.001). The highest microhardness values were found in glass fiber-reinforcement group (76.48 ± 17.07, p < 0.001). CONCLUSION Single-shade resin composites were more translucent, had higher color change, and lower hardness than multi-shade resin composite. For relative translucency and microhardness, statistical significance was found in the material and fiber type interaction. The glass fiber-reinforcement provided higher translucency, lower color change and higher microhardness values than polyethylene fiber-reinforcement group after aging. Thermocycling had a significant impact on the color stability, translucency parameter, and microhardness of the tested resin composite materials. CLINICAL SIGNIFICANCE Single-shade resin composite materials have greater color-changing potential. The glass fiber-reinforcement optimize resin material mechanical properties and color stability more than polyethylene fiber-reinforcement.
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Affiliation(s)
- Muhammet Fidan
- Department of Restorative Dentistry, Faculty of Dentistry, Usak University, Usak, Turkey
| | - Özhan Yağci
- Department of Restorative Dentistry, Faculty of Dentistry, Usak University, Usak, Turkey
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Ravi B, Paulraj J, Maiti S, Shanmugam R. Assessing the Influence of Thermocycling on Compressive Strength, Flexural Strength, and Microhardness in Green-Mediated Nanocomposite-Enhanced Glass Ionomer Cement Compared to Traditional Glass Ionomer Cement. Cureus 2024; 16:e56078. [PMID: 38618398 PMCID: PMC11009900 DOI: 10.7759/cureus.56078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 03/13/2024] [Indexed: 04/16/2024] Open
Abstract
Background and objective Glass ionomer cement (GIC), also known as polyalkenoate cement, has been extensively used in dentistry for both luting and restorative purposes. Despite being the first choice for aesthetic restorations due to their chemical bonding ability to teeth, GICs have faced challenges such as low mechanical properties, abrasion resistance, and sensitivity to moisture, leading to the search for improved materials. This study aims to assess the effects of thermocycling on the compressive, flexural strength, and microhardness of green-mediated nanocomposite-modified GIC in comparison to traditional GIC. Methodology Green-mediated nanoparticles, consisting of chitosan, titanium, zirconia, and hydroxyapatite (Ch-Ti-Zr-HA), were synthesized using a one-pot synthesis technique to form nanocomposites. These nanocomposites were then incorporated into GIC specimens in varying concentrations (3%, 5%, and 10%), denoted as Group I, Group II, and Group III, respectively. Group IV served as the control, consisting of conventional GIC. To assess the performance of the novel restorative materials over an extended period, compressive strength, flexural strength, and microhardness were measured before and after thermocycling using a universal material testing machine. Furthermore, scanning electron microscopy (SEM) analysis was carried out following the thermocycling process. The collected data were subjected to statistical analysis through one-way analysis of variance (ANOVA) and paired t-tests. Results The findings demonstrated that, in comparison to the control group, both the mean compressive strength and flexural strength, as well as hardness, were notably higher for the 10% and 5% nanocomposite-modified GIC specimens before and after thermocycling (P < 0.05). Notably, there was no notable difference observed between the 5% and 10% concentrations (P > 0.05). These results suggest that incorporating green-mediated nanocomposites (Ch-Ti-Zr-HA) modified GIC at either 5% or 10% concentration levels leads to improved mechanical properties, indicating their potential as promising alternatives in dental restorative materials. Conclusions Based on our findings, it can be inferred that the 10% and 5% concentrations of green-mediated (Ch-Ti-Zr-HA) modified GIC exhibit superior compressive and flexural strength compared to conventional GIC. Additionally, analysis of the scanning electron microscope (SEM) morphology revealed that green-mediated GIC displays smoother surface characteristics in contrast to conventional GIC. These results underscore the potential advantages of utilizing green-mediated nanocomposite-modified GIC in dental applications, suggesting enhanced mechanical properties and surface quality over conventional.
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Affiliation(s)
- Bharath Ravi
- Department of Pedodontics and Preventive Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Jessy Paulraj
- Department of Pedodontics and Preventive Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Subhabrata Maiti
- Department of Prosthodontics, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Rajeshkumar Shanmugam
- Nanobiomedicine Lab, Centre for Global Health Research, Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, IND
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Kavoor S, Ranjini MA, Aziz NA, Ashok HK, Nadig RR. In vitro evaluation of the effect of addition of biomaterials to carbamide peroxide on the bleaching efficacy and microhardness of enamel. J Conserv Dent Endod 2024; 27:310-314. [PMID: 38634034 PMCID: PMC11019809 DOI: 10.4103/jcde.jcde_310_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/19/2024] [Accepted: 02/12/2024] [Indexed: 04/19/2024]
Abstract
Background and Aim Teeth bleaching, although considered safe and conservative, cause microscopic changes in the tooth structure. The aim of this study is to evaluate the bleaching efficacy of carbamide peroxide (CP) bleaching gel when modified with the incorporation of bioactive glass (BG) and hydroxyapatite (HA) and its effect on enamel microhardness. Materials and Methods Forty-five maxillary incisors were decoronated, artificially stained and mounted in acrylic. The samples were divided into three groups of 15 each and subjected to the following bleaching protocol for 8 h/day at 37°C for 2 weeks: Group 1 - 16% CP, Group 2 - CP modified with BG, and Group 3 - CP modified with hydroxyapatite (HA). Spectrophotometric color assessment using CIE L*a*b* system and Vickers microhardness were assessed before and after bleaching. Data were analyzed using Student's paired t-test and one-way ANOVA followed by Tukey's post hoc analysis. Results There was a significant change in color (L*a*b*) in all the three groups when compared to the baseline values. However, no significant difference in the total color change (ΔE) was observed between the three groups. Enamel microhardness reduced significantly in the CP group, whereas it increased in the BG and HA group after bleaching. Scanning electron microscopy images of BG and HA groups showed crystalline deposits suggesting mineral deposition. Conclusion Addition of biomaterials can be a beneficial alternative to bleaching with CP alone, considering the increase in microhardness without hindering the bleaching action.
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Affiliation(s)
- Sowmya Kavoor
- Department of Conservative Dentistry and Endodontics, Dayananda Sagar College of Dental Sciences, Bengaluru, Karnataka, India
| | - M. A. Ranjini
- Department of Conservative Dentistry and Endodontics, Dayananda Sagar College of Dental Sciences, Bengaluru, Karnataka, India
| | - Naval Abdul Aziz
- Department of Conservative Dentistry and Endodontics, Dayananda Sagar College of Dental Sciences, Bengaluru, Karnataka, India
| | - H. K. Ashok
- Department of Conservative Dentistry and Endodontics, Dayananda Sagar College of Dental Sciences, Bengaluru, Karnataka, India
| | - Roopa R. Nadig
- Department of Conservative Dentistry and Endodontics, Dayananda Sagar College of Dental Sciences, Bengaluru, Karnataka, India
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Güçlü ZA, Patat Ş, Coleman NJ. The Impact of Nano- and Micro-Silica on the Setting Time and Microhardness of Conventional Glass-Ionomer Cements. Dent J (Basel) 2024; 12:54. [PMID: 38534278 DOI: 10.3390/dj12030054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/07/2024] [Accepted: 02/22/2024] [Indexed: 03/28/2024] Open
Abstract
The objective of this study was to investigate the effect of the incorporation of 2, 4 or 6 wt% of amorphous nano- or micro-silica (Aerosil® OX 50 or Aeroperl® 300 Pharma (Evonik Operations GmbH, Essen, Germany), respectively) on the net setting time and microhardness of Ketac™ Molar (3M ESPE, St. Paul, MN, USA) and Fuji IX GP® (GC Corporation, Tokyo, Japan) glass-ionomer cements (GICs) (viz. KM and FIX, respectively). Both silica particles were found to cause a non-linear, dose-dependent reduction in setting time that was within the clinically acceptable limits specified in the relevant international standard (ISO 9917-1:2007). The microhardness of KM was statistically unaffected by blending with 2 or 4 wt% nano-silica at all times, whereas 6 wt% addition decreased and increased the surface hardness at 1 and 21 days, respectively. The incorporation of 4 or 6 wt% nano-silica significantly improved the microhardness of FIX at 1, 14 and 21 days, with no change in this property noted for 2 wt% addition. Micro-silica also tended to enhance the microhardness of FIX, at all concentrations and times, to an extent that became statistically significant for all dosages at 21 days. Conversely, 4 and 6 wt% additions of micro-silica markedly decreased the initial 1-day microhardness of KM, and the 21-day sample blended at 4 wt% was the only specimen that demonstrated a significant increase in this property. Scanning electron microscopy indicated that the nano- and micro-silica particles were well distributed throughout the composite structures of both GICs with no evidence of aggregation or zoning. The specific mechanisms of the interaction of inorganic nanoparticles with the constituents of GICs require further understanding, and a lack of international standardization of the determination of microhardness is problematic in this respect.
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Affiliation(s)
- Zeynep A Güçlü
- Department of Pediatric Dentistry, Faculty of Dentistry, Erciyes University, Melikgazi, Kayseri 38039, Türkiye
- ERNAM, Erciyes University Nanotechnology Application & Research Center, Erciyes University, Melikgazi, Kayseri 38039, Türkiye
| | - Şaban Patat
- Department of Chemistry, Faculty of Science, Erciyes University, Melikgazi, Kayseri 38010, Türkiye
| | - Nichola J Coleman
- Department of Pediatric Dentistry, Faculty of Dentistry, Erciyes University, Melikgazi, Kayseri 38039, Türkiye
- School of Science, Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TB, UK
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Khairy NM, Elkholany NR, Elembaby AE. Evaluation of surface microhardness and gingival marginal adaptation of three different bulk-fill flowable resin composites: A comparative study. J ESTHET RESTOR DENT 2024. [PMID: 38404208 DOI: 10.1111/jerd.13211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/03/2024] [Accepted: 02/09/2024] [Indexed: 02/27/2024]
Abstract
OBJECTIVES To evaluate surface microhardness and gingival marginal adaptation of three different bulk-fill flowable resin composites (FB-RBCs) in Class V cavities with enamel or dentin margins before and after thermocycling (TMC). MATERIALS AND METHODS Three available FB-RBCs were used; Palfique Bulk Flow (PaBF) (Tokuyama Dental), SDR Flow+ Bulk Fill Flowable (Dentsply Sirona), and I-Flow Bulk Fill (I-Dental). Thirty discs were prepared from each type of FB-RBCs. The discs were subjected to Vickers microhardness tester machine. Class V cavities were prepared on 180 molars. Gingival margins of half the specimens were prepared above CEJ and the other half below CEJ. Cavities were restored with FB-RBCs for gingival marginal adaptation test. Two-way ANOVA was used in microhardness, while three-way ANOVA was used for marginal adaptation. RESULTS The used materials showed statistically significant differences in microhardness and marginal adaptation. CONCLUSIONS Regarding microhardness, PaBF showed the highest value before TMC and SDR was the highest after TMC. Regarding marginal adaptation, SDR revealed the best marginal adaptation than PaBF and I-flow, either subjected to TMC or not. CLINICAL SIGNIFICANCE The longevity of cervical restorations depend on both the location of the cavity margin and the material used. The microfractures in resin composite surface due to low surface microhardness as well as marginal gaps seen in laboratory studies could be considered as an indicative parameter for clinical problem associated with marginal differences.
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Affiliation(s)
- Nourhan Medhat Khairy
- Conservative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Aldakhlia, Egypt
| | - Naglaa Rizk Elkholany
- Conservative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Aldakhlia, Egypt
| | - Abeer Elsayed Elembaby
- Conservative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Aldakhlia, Egypt
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Murugan SP, George G, Jaisingh J. Wear performance of Ti-based alloy coatings on 316L SS fabricated with the sputtering method: Relevance to biomedical implants. Biomed Mater Eng 2024:BME230127. [PMID: 38393887 DOI: 10.3233/bme-230127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2024]
Abstract
BACKGROUND This investigation was conducted to encapsulate 316L SS with a Ti-based alloy coating. OBJECTIVE The aim was to fabricate a coating using TiN, TiO2, and TiCoCr powders on 316L SS through the physical vapor deposition (PVD) sputtering process. METHODS The powders were consecutively coated on 316L SS through the PVD sputtering process with coating durations of 30, 60, and 90 min. Further microhardness, surface roughness, microabrasion, and adhesion strength tests were also carried out. RESULTS A 60% improvement in abrasion resistance was observed in TiCoCr-coated samples compared to the uncoated substrate. The X-ray diffraction results confirmed the optimal formation of Ti alloy coatings with corresponding orientation over the SS substrates. Moreover, TiCoCr with a 90 min coating duration had much better surface characteristics than TiO2 and TiN. CONCLUSION The 90 min coating duration should be optimal for coating in steel for bio-implants.
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Affiliation(s)
- Shunmuga Priyan Murugan
- Department of Mechanical Engineering, Loyola Institute of Technology and Science, Thovalai, Tamil Nadu, India
| | - Godwin George
- Department of Mechanical Engineering, Loyola Institute of Technology and Science, Thovalai, Tamil Nadu, India
| | - Julyes Jaisingh
- Department of Mechanical Engineering, Loyola Institute of Technology and Science, Thovalai, Tamil Nadu, India
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11
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Sundaram R, Nachimuthu R, Sivanandam AK, Natarajan J. Electrochemical and hot corrosion behaviour of steel reinforced with AlSiBeTiV high entropy alloy using friction stir processing. Sci Technol Adv Mater 2024; 25:2320083. [PMID: 38419800 PMCID: PMC10901189 DOI: 10.1080/14686996.2024.2320083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 02/13/2024] [Indexed: 03/02/2024]
Abstract
A lightweight AlSiBeTiV high entropy alloy (HEA) powder is synthesized by the ball milling process and is reinforced on SS410 through friction stir processing (FSP). Subsequently, the annealing process is conducted on the processed samples at 450, 600, and 750°C for 120 mins. The grains are refined at 600°C by 23.3% than the processed HEA sample. A higher microhardness of 672 HV is attained on the processed HEA sample annealed at 600°C due to the synergistic effect of FSP and annealing through refined grains. The electrochemical corrosion under a 3.5 wt.% NaCl environment, and the hot corrosion under the salt mixture environments of 75% Na2SO4 +25% NaCl, and 60% Na2SO4 +20% NaCl + 20% V2O5 at 800°C for 50 h are investigated on the processed samples. The microstructure, induced corrosion products, and elemental distribution of the corroded surface of the annealed processed HEA sample are evaluated by morphological analysis. The induced oxidation effect enhances the Cr2O3 and TiO2 films on the corroded surfaces leading to higher corrosion resistance. A high corrosion resistance appears on the annealed processed HEA sample through the formation of a stable passive layer, hindering the pitting corrosion mechanism, grain refinement, and homogeneous distribution.
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Affiliation(s)
- Ragunath Sundaram
- Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, India
| | - Radhika Nachimuthu
- Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, India
| | - Aravind Krishna Sivanandam
- Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, India
| | - Jeyaprakash Natarajan
- School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou, China
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12
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Meng Y, Zhang B, Wang J, Hong Z, Zhao H, Yan N, Hu L. Effects of Ni Content and Heat Treatment on the Properties, Microstructures, and Precipitates of Cu-0.2 wt% Be-x wt% Ni Alloys. Materials (Basel) 2024; 17:816. [PMID: 38399066 PMCID: PMC10890441 DOI: 10.3390/ma17040816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024]
Abstract
Cu-Be alloys exhibit excellent comprehensive performance in electrics, thermotics, and mechanics, and hence, they attract much attention. Among them, low-Be copper alloys are more environmentally friendly and promising. This study explores the effects of different Ni contents and heat treatment parameters on the properties, microstructures, and precipitates of Cu-0.2 wt% Be-x wt% Ni (0 < x < 2.0) alloys. The experimental results demonstrate that the fast cooling rate of cast alloys during solidification contributes to retention of the solute atoms in the copper matrix, which is beneficial for subsequent solid solution treatment. Furthermore, solid solution treatment slightly reduces the electrical conductivities, microhardness values, and compressive yield strengths of Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The optimal solution temperature and time are about 925 ℃ and 60 min, respectively. Aging treatment significantly increases the electrical conductivities, microhardness values, and compressive yield strengths of Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The best aging temperature is around 450 ℃. However, the properties of Cu-0.2 wt%Be-0.4 wt%Ni alloys remain unaffected by solution and aging treatments. Around x = 1.0, Cu-0.2 wt% Be-x wt% Ni alloys possess the best comprehensive properties, which are about 72%IACS of electrical conductivity, 241 HV of microhardness, and 281MPa of compressive yield strength, respectively. TEM and EDS analyses reveal that the precipitate evolution of Cu-0.2 wt% Be-1.0 wt% Ni alloys with aging time is GP zones → γ″ → γ'. Notably, a distinct double-peak age strengthening phenomenon emerges with Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The precipitation of plenty of GP zones at the early stage of aging should account for the first strengthening peak, and the strengthening mechanism transformation of the γ″ or γ' phase from shear to Orowan should induce the second strengthening peak. This work may help to design new low-Be copper alloys and their preparation processes.
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Affiliation(s)
- Yuhan Meng
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; (Y.M.); (B.Z.); (J.W.); (N.Y.); (L.H.)
| | - Bowen Zhang
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; (Y.M.); (B.Z.); (J.W.); (N.Y.); (L.H.)
| | - Jinyun Wang
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; (Y.M.); (B.Z.); (J.W.); (N.Y.); (L.H.)
| | - Zhenyu Hong
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; (Y.M.); (B.Z.); (J.W.); (N.Y.); (L.H.)
| | - Hongliang Zhao
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China;
| | - Na Yan
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; (Y.M.); (B.Z.); (J.W.); (N.Y.); (L.H.)
| | - Liang Hu
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China; (Y.M.); (B.Z.); (J.W.); (N.Y.); (L.H.)
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Iordache SM, Iordache AM, Gatin DI, Grigorescu CEA, Ilici RR, Luculescu CR, Gatin E. Performance Assessment of Three Similar Dental Restorative Composite Materials via Raman Spectroscopy Supported by Complementary Methods Such as Hardness and Density Measurements. Polymers (Basel) 2024; 16:466. [PMID: 38399844 PMCID: PMC10893299 DOI: 10.3390/polym16040466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 02/25/2024] Open
Abstract
(1) Background: A widespread problem in oral health is cavities produced by cariogenic bacteria that consume fermentable carbohydrates and lower pH to 5.5-6.5, thus extracting Ca2+ and phosphate ions (PO43-) from teeth. Dental restorative materials based on polymers are used to fill the gaps in damaged teeth, but their properties are different from those of dental enamel. Therefore, a question is raised about the similarity between dental composites and natural teeth in terms of density and hardness. (2) Methods: We have used Raman spectroscopy and density and microhardness measurements to compare physical characteristics of several restorative dental composites at different polymerization intervals. (3) Results: XRVHerculite®, Optishade®, and VertiseFlow® showed the very different characteristics of the physical properties following four polymerization intervals. Of the three composites, OptiShade showed the highest polymerization rate. (4) Conclusions: Only fully polymerized composites can be used in teeth restoring, because incomplete polymerization would result in cracks, pitting, and lead finally to failure.
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Affiliation(s)
- Stefan-Marian Iordache
- Optospintronics Department, National Institute for Research and Development in Optoelectronics—INOE 2000, 077125 Magurele, Romania; (S.-M.I.); (A.-M.I.); (C.E.A.G.)
| | - Ana-Maria Iordache
- Optospintronics Department, National Institute for Research and Development in Optoelectronics—INOE 2000, 077125 Magurele, Romania; (S.-M.I.); (A.-M.I.); (C.E.A.G.)
| | - Dina Ilinca Gatin
- Faculty of Dentistry, University of Medicine and Pharmacy “Carol Davila”, 020021 Bucharest, Romania; (D.I.G.); (R.R.I.)
| | - Cristiana Eugenia Ana Grigorescu
- Optospintronics Department, National Institute for Research and Development in Optoelectronics—INOE 2000, 077125 Magurele, Romania; (S.-M.I.); (A.-M.I.); (C.E.A.G.)
| | - Roxana Romanita Ilici
- Faculty of Dentistry, University of Medicine and Pharmacy “Carol Davila”, 020021 Bucharest, Romania; (D.I.G.); (R.R.I.)
| | | | - Eduard Gatin
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020021 Bucharest, Romania
- Faculty of Physics, University of Bucharest, 077125 Magurele, Romania
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14
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Baruwa AO, Chasqueira F, Arantes-Oliveira S, Caramês J, Marques D, Portugal J, Martins JNR. Comparative Analysis of Endodontic 0.15 Stainless-Steel K-Files: Exploring Design, Composition, and Mechanical Performance. Dent J (Basel) 2024; 12:29. [PMID: 38392233 PMCID: PMC10887620 DOI: 10.3390/dj12020029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/14/2024] [Accepted: 01/30/2024] [Indexed: 02/24/2024] Open
Abstract
To establish a glide path, smaller files (up to size 0.15) with tapers of 2% are commonly used as pathfinding files. They pre-shape the root canal space before transitioning to larger taper endodontic instruments, aiming to prevent procedural errors. This study aimed to compare the design, metal wire composition, and mechanical characteristics of seven different ISO size 15 stainless-steel hand files (K-File and C-File+). Ninety-one new stainless-steel ISO 15 K-files were mechanically tested. All files were inspected for deformations before the assessment. Dental operating microscope, scanning electron microscope (SEM), and optical microscope analyses were conducted on four randomly selected instruments from each group, and two instruments per group underwent an energy-dispersive X-ray spectroscopy (EDS) analysis. Buckling mechanical tests were performed using an Instron universal testing machine, and microhardness was assessed using a Vickers hardness tester. The statistical analysis employed the nonparametric Mood's median test, with a significance level set at 0.05. The instrument design analysis unveiled variations in the active blade area length and the number of spirals, while maintaining consistent cross-sections and symmetrical blades. Distinct tip geometries and surface irregularities were observed. While the energy-dispersive X-ray spectroscopy confirmed similar compositions, the buckling strength and microhardness values exhibited variability across for all tested files. Notably, the Dentsply ReadySteel C-File+ recorded the highest buckling value (2.10 N), and the Dentsply ReadySteel K-File exhibited the lowest (1.00 N) (p < 0.05). Moreover, the Dentsply ReadySteel K-File recorded the highest microhardness value (703 HVN), while the SybronEndo Triple-Flex had the lowest (549 HVN) (p < 0.05). While similarities in cross-section design and metal wire composition were noted among the files, variations in the number of spirals and mechanical performance were also observed. Thus, all of these factors should be considered when selecting suitable files for an efficient root canal treatment.
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Affiliation(s)
| | - Filipa Chasqueira
- Instituto Universitário Egas Moniz, 2829-511 Monte da Caparica, Portugal
| | - Sofia Arantes-Oliveira
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal
- Grupo de Investigação em Materiais Dentários (BIOMAT), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), FMDUL, 1600-277 Lisboa, Portugal
- LIBPhys-FCT UID/FIS/04559/2013, 1600-277 Lisboa, Portugal
| | - João Caramês
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal
- LIBPhys-FCT UID/FIS/04559/2013, 1600-277 Lisboa, Portugal
- Instituto de Implantologia, 1070-064 Lisboa, Portugal
| | - Duarte Marques
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal
- LIBPhys-FCT UID/FIS/04559/2013, 1600-277 Lisboa, Portugal
- Instituto de Implantologia, 1070-064 Lisboa, Portugal
- Centro de Estudos de Medicina Dentária Baseada na Evidência (CEMDBE), 1600-277 Lisboa, Portugal
- Grupo de Investigação em Bioquimica e Biologia Oral (GIBBO), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), 1600-277 Lisboa, Portugal
| | - Jaime Portugal
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal
- Grupo de Investigação em Materiais Dentários (BIOMAT), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), FMDUL, 1600-277 Lisboa, Portugal
| | - Jorge N R Martins
- Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisboa, Portugal
- Instituto de Implantologia, 1070-064 Lisboa, Portugal
- Centro de Estudos de Medicina Dentária Baseada na Evidência (CEMDBE), 1600-277 Lisboa, Portugal
- Grupo de Investigação em Bioquimica e Biologia Oral (GIBBO), Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), 1600-277 Lisboa, Portugal
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15
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Cerezo PM, Aguilera JA, Garcia-Gonzalez A, Lopez-Crespo P. Microhardness and Microstructure Analysis of the LPBF Additively Manufactured 18Ni300. Materials (Basel) 2024; 17:661. [PMID: 38591549 PMCID: PMC10856223 DOI: 10.3390/ma17030661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/16/2024] [Accepted: 01/22/2024] [Indexed: 04/10/2024]
Abstract
This research focuses on analysing the 18Ni300 maraging steel produced through laser powder bed fusion. Specifically, it aims to examine the phase components using X-ray diffraction, the microstructure through scanning electron microscopy, and the hardness of the different structures present in the manufactured material. The primary goal is to meticulously analyse the material and its microstructures. By doing so, a correlation between the hardness and each structure type, be it cellular or columnar, can be established. This will allow us to pinpoint any defects in the material before any surface chemical treatment is carried out and facilitate a thorough examination of its microstructure. A consistent pattern emerges across the samples through systematic measurement of microhardness distribution in various locations and detailed examination of the structure. The findings of the study reveal that the hardness of cellular and columnar structures exhibits a significant variation based on the location of the measurement about cell boundaries. The hardness value is notably higher in the combination of cellular and multiple layers, as the data indicate.
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Affiliation(s)
| | | | | | - Pablo Lopez-Crespo
- Department of Civil and Materials Engineering, University of Malaga, C/Dr Ortiz Ramos, s/n, 29071 Malaga, Spain; (P.M.C.); (J.A.A.); (A.G.-G.)
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16
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Zaharia SM, Lancea C, Kruk A, Cempura G, Gruszczyński A, Chicos LA, Pop MA. Mechanical Properties and Microstructure of Inconel 718 Lattice Structures Produced by Selective Laser Melting Process. Materials (Basel) 2024; 17:622. [PMID: 38591450 PMCID: PMC10856450 DOI: 10.3390/ma17030622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 01/18/2024] [Accepted: 01/24/2024] [Indexed: 04/10/2024]
Abstract
This article presents the results of an analysis regarding the microstructure, mechanical strength, and microhardness of two kinds of samples built through selective laser melting with Inconel 718, the most frequently used alloy in metal additive manufacturing due to its excellent mechanical properties. The sample geometry was made up of two types of lattice structures with spherical and hyperbolical stiffness elements. The goals of these studies are to determine how homogenization heat treatment influences the microhardness and the mechanical properties of the specimens and to identify the structure with the best mechanical properties. The analysis showed that heat treatment was beneficial because the regular dendritic structure disappears, the δ phase precipitates at the grain boundaries, and both the γ and γ″ phases dissolve. It has also been shown that the structures with hyperbolical stiffness elements have better compressive strength than the structures with the elliptical structures, with a 47.6% increase for the as-fabricated structures and an approximate 50% increase for the heat-treated structure.
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Affiliation(s)
- Sebastian-Marian Zaharia
- Department of Manufacturing Engineering, Transilvania University of Brasov, 500036 Brasov, Romania; (S.-M.Z.); (L.-A.C.)
| | - Camil Lancea
- Department of Manufacturing Engineering, Transilvania University of Brasov, 500036 Brasov, Romania; (S.-M.Z.); (L.-A.C.)
| | - Adam Kruk
- Faculty of Metals Engineering and Industrial Computer Science, AGH University of Krakow, 30 Mickiewicza Ave, 30-059 Krakow, Poland; (A.K.); (G.C.); (A.G.)
| | - Grzegorz Cempura
- Faculty of Metals Engineering and Industrial Computer Science, AGH University of Krakow, 30 Mickiewicza Ave, 30-059 Krakow, Poland; (A.K.); (G.C.); (A.G.)
| | - Adam Gruszczyński
- Faculty of Metals Engineering and Industrial Computer Science, AGH University of Krakow, 30 Mickiewicza Ave, 30-059 Krakow, Poland; (A.K.); (G.C.); (A.G.)
| | - Lucia-Antoneta Chicos
- Department of Manufacturing Engineering, Transilvania University of Brasov, 500036 Brasov, Romania; (S.-M.Z.); (L.-A.C.)
| | - Mihai Alin Pop
- Department of Materials Science, Transilvania University of Brasov, 500036 Brasov, Romania;
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17
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Mao Y, Gao Y, Hu J, Shen X, Zhou H. Effect of Hatch Spacing on the Quality of Inconel 718 Alloy Part. Materials (Basel) 2024; 17:452. [PMID: 38255620 PMCID: PMC10817345 DOI: 10.3390/ma17020452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 01/24/2024]
Abstract
Selective laser melting (SLM) has attracted increasing attention all over the world. As an important parameter, hatch spacing, which is the distance between scan lines, however, still needs a more systematic study. In this paper, the relationship between hatch spacing and mechanical properties, including microhardness, wear resistance, and porous density, was studied. The testing results revealed that when hatch spacing decreased, the overlapping rate increased which resulted in an increase in the convection in the molten pool. It led to the formation of pores in the molten pool. However, when hatch spacing was too large, the overlapping zone decreased, while the strength between each welding line was not strong enough. It caused a decrease in the quality of printed parts. Combined with the testing results gained in this work, it can be seen that a 0.06 mm hatch spacing was considered as a relatively optimal condition for part formation under 0.05 μm. Comparison of the morphology of the samples printed under different hatch spacing also confirmed the phenomenon observed here.
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Affiliation(s)
- Yuyi Mao
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China;
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Yintao Gao
- Wuxi Institution of Inspection, Testing and Certification, Wuxi 214028, China; (Y.G.); (J.H.)
| | - Juan Hu
- Wuxi Institution of Inspection, Testing and Certification, Wuxi 214028, China; (Y.G.); (J.H.)
| | - Xiaodong Shen
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China;
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Hao Zhou
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China
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Gasha SB, Trautmann M, Wagner G. Effect of Milling Time and Reinforcement Volume Fraction on Microstructure and Mechanical Properties of SiC p-Reinforced AA2017 Composite Powder Produced by High-Energy Ball Milling. Materials (Basel) 2024; 17:435. [PMID: 38255603 PMCID: PMC10821172 DOI: 10.3390/ma17020435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/10/2024] [Accepted: 01/13/2024] [Indexed: 01/24/2024]
Abstract
The influence of milling time and volume fraction of reinforcement on the morphology, microstructure, and mechanical behaviors of SiCp-reinforced AA2017 composite powder produced by high-energy ball milling (HEBM) was investigated. AA2017 + SiCp composite powder with different amounts of SiC particles (5, 10, and 15 vol%) was successfully prepared from gas-atomized AA2017 aluminum alloy powder with a particle size of <100 μm and silicon carbide (SiC) powder particles with an average particle size of <1 μm. An optical microscope (OM), X-ray diffraction (XRD), and scanning electron microscope (SEM) were utilized to characterize the microstructure of the milled composite powder at different milling periods. The results indicated that the SiC particles were homogeneously distributed in the AA2017 matrix after 5 h of HEBM time. The morphology of the particles transformed from a laminar to a nearly spherical shape, and the size of the milled powder particles reduced with increasing the content of SiC particles. The XRD analysis was carried out to characterize the phase constituents, crystallite size, and lattice strain of the composite powders at different milling periods. It was found that with increasing milling time and SiC volume fraction, the crystallite size of the aluminum alloy matrix decreased while the lattice strain increased. The average crystallite sizes were reduced from >300 nm to 68 nm, 64 nm, and 64 nm after 5 h of milling, corresponding to SiC contents of 5, 10, and 15 vol%, respectively. As a result, the lattice strain increased from 0.15% to 0.5%, which is due to significant plastic deformation during the ball milling process. XRD results showed a rapid decrease in crystallite size during the early milling phase, and the minimum grain size was achieved at a higher volume fraction of SiC particles. Microhardness tests revealed that the milling time has a greater influence on the hardness than the amount of SiC reinforcements. Therefore, the composite powder milled for 5 h showed an average microhardness three times higher than that of the unmilled powder particles.
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Affiliation(s)
- Shimelis Bihon Gasha
- Professorship of Composites and Material Compounds, Institute of Materials Science and Engineering (IWW), Chemnitz University of Technology, 09125 Chemnitz, Germany; (M.T.); (G.W.)
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19
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Rosolymou E, Karantonis A, Pavlatou EA. Effects of Direct and Pulse Plating on the Co-Deposition of Sn-Ni/TiO 2 Composite Coatings. Materials (Basel) 2024; 17:392. [PMID: 38255562 PMCID: PMC10821509 DOI: 10.3390/ma17020392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/05/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024]
Abstract
Sn-Ni alloy matrix coatings co-deposited with TiO2 nanoparticles (Evonik P25) were produced utilizing direct (DC) and pulse electrodeposition (PC) from a tin-nickel chloride-fluoride electrolyte with a loading of TiO2 nanoparticles equal to 20 g/L. The structural and morphological characteristics of the resultant composite coatings were correlated with the compositional modifications that occurred within the alloy matrix and expressed via a) TiO2 co-deposition rate and b) composition of the matrix; this was due to the application of different current types (DC or PC electrodeposition), and different current density values. The results demonstrated that under DC electrodeposition, the current density exhibited a more significant impact on the composition of the alloy matrix than on the incorporation rate of the TiO2 nanoparticles. Additionally, PC electrodeposition favored the incorporation rate of TiO2 nanoparticles only when applying a low peak current density (Jp = 1 Adm-2). All of the composite coatings exhibited the characteristic cauliflower-like structure, and were characterized as nano-crystalline. The composites' surface roughness demonstrated a significant influence from the TiO2 incorporation rate. However, in terms of microhardness, higher co-deposition rates of embedded TiO2 nanoparticles within the alloy matrix were associated with decreased microhardness values. The best wear performance was achieved for the composite produced utilizing DC electrodeposition at J = 1 Adm-2, which also demonstrated the best photocatalytic behavior under UV irradiation. The corrosion study of the composite coatings revealed that they exhibit passivation, even at elevated anodic potentials.
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Affiliation(s)
- Eleni Rosolymou
- Laboratory of General Chemistry, School of Chemical Engineering, National Technical University of Athens, 9, Heroon Polytechniou Str., Zografos Campus, GR-15780 Athens, Greece
| | - Antonis Karantonis
- Laboratory of Physical Chemistry and Applied Electrochemistry, School of Chemical Engineering, National Technical University of Athens, Zografou, GR-15780 Athens, Greece;
| | - Evangelia A. Pavlatou
- Laboratory of General Chemistry, School of Chemical Engineering, National Technical University of Athens, 9, Heroon Polytechniou Str., Zografos Campus, GR-15780 Athens, Greece
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Kostadinov G, Penyashki T, Nikolov A, Vencl A. Improving the Surface Quality and Tribological Characteristics of 3D-Printed Titanium Parts through Reactive Electro-Spark Deposition. Materials (Basel) 2024; 17:382. [PMID: 38255549 PMCID: PMC10817268 DOI: 10.3390/ma17020382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 12/28/2023] [Accepted: 01/08/2024] [Indexed: 01/24/2024]
Abstract
This work presents the results of research conducted with an aim to improve the surface quality, hardness and wear resistance of titanium alloy Ti6Al4V, obtained via the laser powder bed fusion of metals (PBF-LB/M) process of additive manufacturing (AM) known as the 3D printing of metals. The 3D surfaces were coated via reactive electrospark deposition (RESD) with low-pulse energy and electrode materials of low-melting metals and multi-component hard alloys. The relationship between the electrical parameters of the RESD process and the quality, composition, structure, microhardness and wear resistance of the treated surfaces were investigated and analysed. It was found that the roughness and thickness of the resulting surface layers could be changed by changing the RESD modes within the limits of 2.5-5 µm and 8-20 µm, respectively. RESD processing allowed us to achieve two to five times lower roughness than that of titanium AM surfaces. The microhardness and wear resistance of the RESD surfaces are two to four times higher than those of the titanium substrate. Possibilities for the purposeful synthesis of new wear-resistant phases and compounds and for obtaining surface layers with predetermined thickness and roughness were established. It was shown that the subsequent reaction's electrospark processing helped to simultaneously reduce the roughness and increase the hardness and wear resistance of the modified surfaces, and can be successfully used instead of the material-energy-labour and machine-intensive finishing treatments of the titanium surfaces obtained after 3D printing.
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Affiliation(s)
- Georgi Kostadinov
- Institute of Soil Science Agrotechnologies and Plant Protection “N. Pushkarov”, Agricultural Academy, Shose Bankya Str. 7, 1331 Sofia, Bulgaria;
| | - Todor Penyashki
- Institute of Soil Science Agrotechnologies and Plant Protection “N. Pushkarov”, Agricultural Academy, Shose Bankya Str. 7, 1331 Sofia, Bulgaria;
| | - Antonio Nikolov
- Faculty of Industrial Technology, Technical University of Sofia, Kliment Ochridsky 8, 1000 Sofia, Bulgaria;
| | - Aleksandar Vencl
- University of Belgrade, Faculty of Mechanical Engineering, Kraljice Marije 16, 11120 Belgrade, Serbia;
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Martínez C, Arcos C, Briones F, Machado I, Sancy M, Bustamante M. The Effect of Adding CeO 2 Nanoparticles to Cu-Ni-Al Alloy for High Temperatures Applications. Nanomaterials (Basel) 2024; 14:143. [PMID: 38251108 PMCID: PMC10820015 DOI: 10.3390/nano14020143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/26/2023] [Accepted: 08/27/2023] [Indexed: 01/23/2024]
Abstract
This work presents the effect of CeO2 nanoparticles (CeO2-NPs) on Cu-50Ni-5Al alloys on morphological, microstructural, degradation, and electrochemical behavior at high temperatures. The samples obtained by mechanical alloying and spark plasma sintering were exposed to a molten eutectic mixture of Li2CO3-K2CO3 for 504 h. The degradation of the materials was analyzed using gravimetry measurements and electrochemical impedance spectroscopy. Different characterization techniques, such as X-ray diffraction and scanning electron microscopy, were used to investigate the phase composition, parameter lattice, and microstructure of Cu-Ni-Al alloys reinforced with CeO2-NPs. The hardness of the composite was also examined using the Vickers hardness test. Gravimetry measurements revealed that the sample with 1 wt.% CeO2-NPs presented the best response to degradation with a less drastic mass variation. Impedance analysis also revealed that by adding 1 wt.% CeO2-NPs, the impedance modulus increased, which is related to a lower porosity of the oxide film or a thicker oxide layer. The microhardness also significantly increased, incorporating 1 wt.% CeO2-NPs, which reduced with higher CeO2-NPs content, which is possibly associated with a more uniform distribution using 1 wt.% CeO2-NPs in the Cu-Ni-Al matrix that avoided the aggregation phenomenon.
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Affiliation(s)
- Carola Martínez
- Departamento de Ingeniería de Obras Civiles, Universidad de La Frontera, Temuco 4811230, Chile;
| | - Camila Arcos
- Departamento de Ingeniería Mecánica y Metalúrgica, Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Francisco Briones
- Escuela de Mecánica, Pontificia Universidad Católica de Valparaíso, Quilpué 2430120, Chile;
| | - Izabel Machado
- Departamento de Engenharia Mecatrônica e Sistemas Mecânicos, Escola Politecnica, Universidade de São Paulo, São Paulo 05508-030, Brazil;
| | - Mamié Sancy
- Escuela de Construcción Civil, Facultad de Ingeniería, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile;
| | - Marion Bustamante
- Departamento de Ingeniería de Obras Civiles, Universidad de La Frontera, Temuco 4811230, Chile;
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Hazar A, Hazar E. Effects of different antiviral mouthwashes on the surface roughness, hardness, and color stability of composite CAD/CAM materials. J Appl Biomater Funct Mater 2024; 22:22808000241248886. [PMID: 38678374 DOI: 10.1177/22808000241248886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2024] Open
Abstract
OBJECTIVE To evaluate the effect of COVID-19 preventive mouthwashes on the surface hardness, surface roughness (Ra), and color change (ΔE) of three different polymer-based composite CAD/CAM materials (Vita Enamic (ENA), Grandio Block (GB), Lava Ultimate (LU)). METHODS A total of 100 rectangular-shaped specimens with dimensions of 2 mm × 7 mm × 12 mm were obtained by sectioning three different CAD/CAM blocks and randomly divided into five subgroups according to the 30 days of mouthwash immersion protocol as follows: Control: artificial saliva, PVP-I: 1% povidone-iodine, HP: 1.5% hydrogen peroxide, CPC: mouthwash containing 0.075% cetylpyridinium chloride, EO: mouthwash containing essential oils. Microhardness, Ra, and ΔE values were measured at baseline and after 30 days of immersion protocols. Data were analyzed using the Wald Chi-square, two-way ANOVA, and post hoc Tukey tests. RESULTS The independent factors (materials and solutions) significantly influenced the microhardness and color (p < 0.001). Ra of the materials was not affected by any of the mouthwashes (p > 0.05). The microhardness and color of each material varied significantly after immersion in PvP-I and HP (p < 0.05). The highest percentage change in microhardness, Ra, and ΔE was found in LU immersed in PvP-I and HP mouthwashes, while the lowest change was found in ENA groups (p < 0.05). CONCLUSION Within the limitations of this study, it was found that the surface hardness and color of tested polymer-based composite CAD/CAM materials are susceptible to degradation and change after 30 days of immersion in 1% PvP-I and 1.5% HP mouthwashes.
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Affiliation(s)
- Ahmet Hazar
- Faculty of Dentistry, Department of Restorative Dentistry, Zonguldak Bülent Ecevit University, Zonguldak, Turkey
| | - Ecehan Hazar
- Faculty of Dentistry, Department of Endodontics, Zonguldak Bülent Ecevit University, Zonguldak, Turkey
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Hernández-Mendieta LA, Scougall-Vilchis RJ, Rodríguez-Vilchis LE, Teutle-Coyotecatl B, Velázquez-Enríquez U, Contreras-Bulnes R. Effect of a demineralization model on the microhardness, surface roughness and topography of giomers: An in vitro study. Microsc Res Tech 2024; 87:65-77. [PMID: 37675958 DOI: 10.1002/jemt.24412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 09/08/2023]
Abstract
The purpose of this study is to compare the effect of a demineralization model on the microhardness, surface roughness, and topography of giomers.Seventy-two discs of six different dental materials in three different presentations (pit and fissure sealant (PFS), flowable and restorative materials) were divided into six groups (n = 12 p/g). Three experimental groups (giomers) consisted of BeautiSealant, Beautifil Flow Plus, and Beautifil II, and three control groups (resin-based materials) were formed using ClinproTM, FiltekTM Z350 XT Flow, and Filtek™ Bulk Fill materials. Vickers microhardness, surface roughness, and topographic analysis with atomic force microscopy were measured at the beginning (0) after four (1) and 7 days (2) of immersion in a demineralizing model. Statistical analysis was performed using One-way and Repeated Measures ANOVA and Pearson's correlation coefficient (p ≤ .05). The microhardness values showed significant variations, except for the G_RM group. All the groups presented significant increases in roughness through the experiment stages, except for RB_PFS in the Ra parameter. The topographic analysis showed variations in the micromorphology, especially in the experimental group at the end of the demineralization model. Finally, there was no correlation between microhardness and surface roughness. The demineralization model decreased the microhardness, with the lowest reductions in the giomers groups. The effect of the demineralizing model on the surface roughness and topography showed an increase in specific patterns for the experimental and control groups. Therefore, their clinical use is recommended. RESEARCH HIGHLIGHTS: The demineralization model decreased the microhardness property of the evaluated materials, with better performance for the giomer groups. The effect of the demineralizing model on surface roughness showed an increase with specific patterns for the experimental and control groups. Although the materials presented changes in their microhardness, roughness, and topography, their clinical use is recommended.
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Affiliation(s)
- Luz Alejandra Hernández-Mendieta
- Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Rogelio José Scougall-Vilchis
- Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Laura Emma Rodríguez-Vilchis
- Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Bernardo Teutle-Coyotecatl
- Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Ulises Velázquez-Enríquez
- Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Universidad Autónoma del Estado de México, Toluca, Estado de México, México
| | - Rosalía Contreras-Bulnes
- Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Universidad Autónoma del Estado de México, Toluca, Estado de México, México
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Hofpeter K, Zehnder M, Hülsmann M, Al-Jadaa A, Deari S. Precision-milled simulated curved root canals in bovine dentine for the assessment of chemo-mechanical root canal preparation. Int Endod J 2024; 57:78-86. [PMID: 37840198 DOI: 10.1111/iej.13988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/14/2023] [Accepted: 10/03/2023] [Indexed: 10/17/2023]
Abstract
AIM The aim was to develop a standardized curved root canal model in bovine dentine and to assess whether that natural substrate would behave differently from the resin in standard plastic training blocks when prepared chemo-mechanically. The impact of substrate microhardness on simulated canal transportation was considered. METHODOLOGY High-precision computer numerical control (CNC) milling was used to recreate a simulated root canal from a resin training block (Endo Training Bloc J-Shape, size 15) in longitudinally sectioned, dis- and re-assembled bovine incisor roots. Optical overlays obtained from 10 resin blocks were used to identify an average canal and program the CNC milling apparatus accordingly. Resin and dentine microhardness were measured. Simulated root canals in resin training blocks and their bovine counterparts were then instrumented at 37°C using Reciproc R25 instruments (VDW) with water or 17% EDTA (n = 10). Open-access image processing software was used to superimpose and analyse pre- and postoperative images obtained with a digital microscope. Centering ratios were averaged to indicate canal transportation. The effects of substrate and irrigant on canal transportation were assessed by two-way anova. RESULTS Superimposed images showed that resin blocks under investigation varied considerably in terms of simulated canal length and curvature, whilst the milled canals were highly similar. The microhardness of dentine was more than three times higher than that of the resin. Conversely, canal transportation was considerably greater in dentine compared to resin, and in dentine had a tendency to be increased by EDTA. There was a strong effect of substrate on canal transportation (p < .001), no overall effect of irrigant, and a marginally significant interaction between irrigant and substrate (p = .077). CONCLUSIONS CNC milling allows to create standardized simulated curved root canals in bovine dentine. These models may be useful to test and compare materials and concepts of chemo-mechanical root canal instrumentation. Microhardness is a bulk feature that does not predict the response to chemo-mechanical instrumentation of a composite material such as dentine.
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Affiliation(s)
- Kevin Hofpeter
- Division of Endodontology, Department of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Matthias Zehnder
- Division of Endodontology, Department of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Michael Hülsmann
- Division of Endodontology, Department of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Anas Al-Jadaa
- Department of Clinical Sciences, College of Dentistry, Ajman University, Ajman, United Arab Emirates
| | - Shengjile Deari
- Division of Endodontology, Department of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Zurich, Switzerland
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Gornakova AS, Kabirova DB, Korneva A, Straumal B, Imayev MF, Kuzmin A, Czaja P, Afonikova NS, Orlov VI, Nekrasov AN, Khayretdinov NF, Davdian G. Effect of High-Pressure Torsion on Phase Formation and Mechanical Properties of a High-Entropy TiZrHfMoCrCo Alloy. Materials (Basel) 2023; 16:7558. [PMID: 38138700 PMCID: PMC10744940 DOI: 10.3390/ma16247558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023]
Abstract
This investigation delved into the alterations in the mechanical properties of a TiZrHfMoCrCo high-entropy alloy due to phase transformations induced by high-pressure torsion (HPT). The alloy's genesis involved levitation melting within an argon atmosphere, presenting two distinct states for analysis: the initial, post-manufacturing state and the state subsequent to HPT treatment. The original alloy featured a composition comprising a singular A2 phase with a bcc lattice and two Laves phases, C15 and C14. The HPT process triggered significant phase modifications: a retention of one C15 Laves phase and decomposition of the bcc phase into two distinct phases exhibiting different bcc lattice parameters. The HPT-induced effect prominently manifests as strong grain refinement. However, scanning electron microscopy (SEM) observations unveiled persistent inhomogeneities at a micron scale both before and after HPT treatment. Thus, grain refinement occurs separately within each of the bcc and Laves phases, visible in the light, dark, and gray areas in SEM images, while mixing does not occur on the scale of several microns. The examination of Ti, Cr, Co, Zr, Mo, and Hf via X-ray absorption spectroscopy (EXAFS) at specific K-edges and L3-edge revealed that the HPT treatment conserves the local atomic environment of metal atoms, albeit with a slight elevation in static disorder. Assessments through microhardness and three-point bending tests demonstrated the material's inherent hardness and brittleness. The microhardness, standing at a substantial value of 600 HV, displayed negligible augmentation post-HPT. However, the microhardness of individual phases exhibited a notable alteration, nearly doubling in magnitude.
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Affiliation(s)
- Alena S. Gornakova
- Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Ac. Osipyan Str. 2, 142432 Chernogolovka, Russia; (A.S.G.); (N.S.A.); (V.I.O.); (G.D.)
| | - Dilara B. Kabirova
- Institute for Metals Superplasticity Problems of Russian Academy of Sciences, Stepan Khalturin Str. 39, 450001 Ufa, Russia; (D.B.K.); (M.F.I.); (N.F.K.)
| | - Anna Korneva
- Institute of Metallurgy and Materials Science Polish Academy of Sciences, Reymonta Str. 25, 30-059 Cracow, Poland; (A.K.); (P.C.)
| | - Boris Straumal
- Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Ac. Osipyan Str. 2, 142432 Chernogolovka, Russia; (A.S.G.); (N.S.A.); (V.I.O.); (G.D.)
- Department of Physical Chemistry, National University of Science and Technology “MISIS”, Leninsky Avenue 4, 119991 Moscow, Russia
| | - Marcel F. Imayev
- Institute for Metals Superplasticity Problems of Russian Academy of Sciences, Stepan Khalturin Str. 39, 450001 Ufa, Russia; (D.B.K.); (M.F.I.); (N.F.K.)
| | - Alexei Kuzmin
- Institute of Solid State Physics, University of Latvia, Kengaraga Str. 8, LV-1063 Riga, Latvia;
| | - Paweł Czaja
- Institute of Metallurgy and Materials Science Polish Academy of Sciences, Reymonta Str. 25, 30-059 Cracow, Poland; (A.K.); (P.C.)
| | - Natalia S. Afonikova
- Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Ac. Osipyan Str. 2, 142432 Chernogolovka, Russia; (A.S.G.); (N.S.A.); (V.I.O.); (G.D.)
| | - Valeriy I. Orlov
- Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Ac. Osipyan Str. 2, 142432 Chernogolovka, Russia; (A.S.G.); (N.S.A.); (V.I.O.); (G.D.)
| | - Alexei N. Nekrasov
- Korzhinskii Institute of Experimental Mineralogy of the Russian Academy of Sciences, Ac. Osipyan Str. 4, 142432 Chernogolovka, Russia;
| | - Nafis F. Khayretdinov
- Institute for Metals Superplasticity Problems of Russian Academy of Sciences, Stepan Khalturin Str. 39, 450001 Ufa, Russia; (D.B.K.); (M.F.I.); (N.F.K.)
| | - Gregory Davdian
- Osipyan Institute of Solid State Physics of the Russian Academy of Sciences, Ac. Osipyan Str. 2, 142432 Chernogolovka, Russia; (A.S.G.); (N.S.A.); (V.I.O.); (G.D.)
- Department of Physical Chemistry, National University of Science and Technology “MISIS”, Leninsky Avenue 4, 119991 Moscow, Russia
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Youssef M, El-Shenawy EH, Khair-Eldeen W, Adachi T, Nofal A, Hassan MA. The Influences of Nb Microalloying and Grain Refinement Thermal Cycling on Microstructure and Tribological Properties of Armox 500T. Materials (Basel) 2023; 16:7485. [PMID: 38068229 PMCID: PMC10707768 DOI: 10.3390/ma16237485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 11/18/2023] [Accepted: 11/23/2023] [Indexed: 03/11/2024]
Abstract
This study aims to investigate the combined effect of niobium (Nb) microalloying and austenite grain refinement, using a specific heat treatment cycle, on the microstructure and tribological properties of Armox 500T steel. In this work, Nb addition and thermal cycling were utilized for grain refinement and enhancement of the mechanical properties of Armox 500T alloy, to provide improved protection via lightweight armor steel components with a high strength-to-weight ratio. The kinetics of transformation of the developed Armox alloys were studied using JMATPro version 13.2. The samples were subjected to two austenitizing temperatures, 1000 °C and 1100 °C, followed by 4 min of holding time and three consecutive thermal and rapid-quenching processes from 900 °C to room temperature. Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) was employed to analyze the microstructure, which primarily consists of four types of martensite: short and long lath martensite, blocky martensite, and equiaxed martensite. Additionally, a small percentage (not exceeding 3%) of carbide precipitates was observed. The wear characteristics of the investigated alloys were evaluated using a pin-on-disc tribometer. The results demonstrate that alloying with Nb and grain refinement using a thermal cycle significantly reduce the wear rate.
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Affiliation(s)
- Mervat Youssef
- School of Innovative Design Engineering (IDE), Egypt-Japan University of Science and Technology (E-JUST), Alexandria 21934, Egypt;
- Metal Casting Department, Manufacturing Technology Institute, Central Metallurgical Research and Development Institute (CMRDI), Cairo 11912, Egypt;
| | - Eman H. El-Shenawy
- Plastic Deformation Department, Metal Technology Institute, Central Metallurgical Research and Development Institute (CMRDI), Cairo 11912, Egypt;
| | - Wael Khair-Eldeen
- School of Innovative Design Engineering (IDE), Egypt-Japan University of Science and Technology (E-JUST), Alexandria 21934, Egypt;
| | - Tadaharu Adachi
- Department of Mechanical Engineering, Toyohashi University of Technology (TUT), Aichi 441-8122, Japan;
| | - Adel Nofal
- Metal Casting Department, Manufacturing Technology Institute, Central Metallurgical Research and Development Institute (CMRDI), Cairo 11912, Egypt;
| | - Mohsen A. Hassan
- School of Innovative Design Engineering (IDE), Egypt-Japan University of Science and Technology (E-JUST), Alexandria 21934, Egypt;
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Irudayaraj N, Rajamani S, Mahalingam P, Karunakaran J, M AH, Chandran DE. Comparative Evaluation of Mechanical Properties and Microleakage of Cention N and Titanium Dioxide Nanoparticles-Enriched Cention N: An In Vitro Study. Cureus 2023; 15:e51209. [PMID: 38283417 PMCID: PMC10818218 DOI: 10.7759/cureus.51209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/27/2023] [Indexed: 01/30/2024] Open
Abstract
Aim This study aimed to assess and compare the mechanical properties, including compressive strength, diametral tensile strength, flexural strength, fracture resistance, microhardness, and microleakage, between Cention N (Ivoclar Vivadent, Gurugram, India) and Cention N enriched with titanium dioxide (TiO2) nanoparticles. Methodology A total of 120 samples were involved in the study, which were split into two experimental groups. For evaluation of each mechanical property, 20 samples were included, of which 10 samples were used for evaluating the properties of Cention N and 10 samples were used for TiO2 nanoparticles-enriched Cention N. Samples, formed using Teflon molds, were filled with Cention N and TiO2-enriched Cention N powders mixed per the manufacturer's instructions. The universal testing machine (UTM) was used to assess compressive, flexural, diametral tensile strength, and fracture resistance. Microhardness was evaluated using a diamond indenter, while microleakage was examined utilizing a stereomicroscope. Results The nanotitania-enriched Cention N showed significantly increased mechanical properties and increased microhardness with the least microleakage. Conclusion The inclusion of TiO2 in Cention N has proved to yield promising results.
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Affiliation(s)
- Nancy Irudayaraj
- Department of Conservative Dentistry and Endodontics, Greater Chennai Corporation, Chennai, IND
| | - Sinduja Rajamani
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Padmapriya Mahalingam
- Department of Conservative Dentistry and Endodontics, Tamil Nadu Government Dental College and Hospital, Chennai, IND
| | - Janani Karunakaran
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Afridh Hameedha M
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Darcus Evangelin Chandran
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
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Alrahlah A, Khan R, Al-Odayni AB, Saeed WS, Bautista LS, Alnofaiy IA, De Vera MAT. Advancing Dimethacrylate Dental Composites by Synergy of Pre-Polymerized TEGDMA Co-Filler: A Physio-Mechanical Evaluation. Biomimetics (Basel) 2023; 8:577. [PMID: 38132515 PMCID: PMC10741395 DOI: 10.3390/biomimetics8080577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/21/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023] Open
Abstract
Dental resin composites (DRCs) have gained immense popularity as filling material in direct dental restorations. They are highly valued for their ability to closely resemble natural teeth and withstand harsh oral conditions. To increase the clinical performance of dental restorations, various fillers are incorporated into DRCs. Herein, the effect of incorporating pre-polymerized triethylene glycol dimethacrylate (P-TEGDMA) as a co-filler in varying proportions (0%, 2.5%, 5%, and 10% by weight) into bisphenol A-glycidyl methacrylate (BisGMA)/TEGDMA/SiO2 resin composite was investigated. The obtained DRCs were examined for morphology, rheological properties, degree of crosslinking (DC), Vickers microhardness (VMH), thermal stability, and flexural strength (FS). The results revealed that SiO2 and P-TEGDMA particles were uniformly dispersed. The introduction of P-TEGDMA particles (2.5 wt.%) into the resin composite had a remarkable effect, leading to a significant reduction (p ≤ 0.05) in complex viscosity, decreasing from 393.84 ± 21.65 Pa.s to 152.84 ± 23.94 Pa.s. As a result, the DC was significantly (p ≤ 0.05) improved from 61.76 ± 3.80% to 68.77 ± 2.31%. In addition, the composite mixture demonstrated a higher storage modulus (G') than loss modulus (G″), indicative of its predominantly elastic nature. Moreover, the thermal stability of the DRCs was improved with the addition of P-TEGDMA particles by increasing the degradation temperature from 410 °C to 440 °C. However, the VMH was negatively affected. The study suggests that P-TEGDMA particles have the potential to be used as co-fillers alongside other inorganic fillers, offering a means to fine-tune the properties of DRCs and optimize their clinical performance.
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Affiliation(s)
- Ali Alrahlah
- Restorative Dental Sciences Department, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia (W.S.S.); (L.S.B.)
| | - Rawaiz Khan
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia (W.S.S.); (L.S.B.)
| | - Abdel-Basit Al-Odayni
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia (W.S.S.); (L.S.B.)
| | - Waseem Sharaf Saeed
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia (W.S.S.); (L.S.B.)
| | - Leonel S. Bautista
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia (W.S.S.); (L.S.B.)
| | - Ibraheem A. Alnofaiy
- Research Center, College of Dentistry, King Saud University, Riyadh 11451, Saudi Arabia; (I.A.A.); (M.A.T.D.V.)
| | - Merry Angelyn Tan De Vera
- Research Center, College of Dentistry, King Saud University, Riyadh 11451, Saudi Arabia; (I.A.A.); (M.A.T.D.V.)
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Song M, Lee SM, Bang JY, Kim RH, Kwak SW, Kim HC. Chemomechanical Properties and Biocompatibility of Various Premixed Putty-type Bioactive Ceramic Cements. J Endod 2023; 49:1713-1721. [PMID: 37734586 DOI: 10.1016/j.joen.2023.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/03/2023] [Accepted: 09/13/2023] [Indexed: 09/23/2023]
Abstract
INTRODUCTION This study aimed to evaluate the chemomechanical properties and biocompatibility of recently introduced premixed putty-type bioactive ceramic cements (PPBCs). METHODS Including ProRoot MTA (PMTA) as a control, BC RRM fast-set putty (BCPT), Well-Root PT (WRPT), One-Fil PT (OFPT), and Endocem MTA premixed (ECPM) were compared to evaluate setting time, radiopacity, pH change, and microhardness. Biocompatibility on human dental pulp cells was compared using CCK-8 assay. Mineralization potential was evaluated using alkaline phosphatase activity, Alizarin Red S (ARS) staining, and quantitative real-time polymerase chain reaction with odontogenic gene marker. For data analysis, 1-way analysis of variance and Tukey's post hoc test were used at the significance level of 95%. RESULTS Among the PPBCs, BCPT presented the longest (552 ± 27) setting time (minutes) and others showed significantly shorter time than PMTA (334 ± 22) (P < .05). WRPT (6.20 ± 0.54) and OFPT (5.82 ± 0.50) showed significantly higher radiopacity values (mmAl) and others showed similar value compared with PMTA (P > .05). All PPBCs showed high alkaline pH from fresh materials and tended to increase according to time periods from 30 minutes to 12 hours. ECPM showed the highest value of microhardness (81.62 ± 5.90), WRPT showed similar, and others showed lower than PMTA (P < .05). All PPBCs showed biocompatibility in CCK-8 assay. All PPBCs showed similar or better value compared with PMTA in ALP and ARS staining, and ALP and DSPP marker expression (P < .05). CONCLUSIONS The PPBCs showed clinically acceptable chemomechanical properties and favorable mineralization potential.
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Affiliation(s)
- Minju Song
- Department of Conservative Dentistry, College of Dentistry, Dankook University, Cheonan, Korea
| | - So-Mang Lee
- Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Dental and Life Science Institute, Pusan National University, Yangsan, Korea
| | - Ji-Young Bang
- Department of Conservative Dentistry, College of Dentistry, Dankook University, Cheonan, Korea
| | - Ruben H Kim
- UCLA Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Sang Won Kwak
- Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Dental and Life Science Institute, Pusan National University, Yangsan, Korea
| | - Hyeon-Cheol Kim
- Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Dental and Life Science Institute, Pusan National University, Yangsan, Korea.
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Çakmak G, Asadolahi NW, Schimmel M, Molinero-Mourelle P, Akay C, Donmez MB, Yilmaz B. Effect of coffee thermal cycling on the surface properties and stainability of additively manufactured denture base resins in different layer thicknesses. J Prosthodont 2023. [PMID: 37968565 DOI: 10.1111/jopr.13803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 10/25/2023] [Accepted: 11/09/2023] [Indexed: 11/17/2023] Open
Abstract
PURPOSE To compare the effect of coffee thermal cycling on surface roughness (Ra), Vickers microhardness (MH), and stainability of denture base resins additively manufactured in different layer thicknesses with those of subtractively manufactured denture base materials. MATERIALS AND METHODS Eighty disk-shaped specimens (Ø10×2 mm) were fabricated from two subtractively (Merz M-PM [SM-M] and G-CAM [SM-G]) and three additively (NextDent 3D+ [50 µm, AM-N-50; 100 µm, AM-N-100], FREEPRINT Denture [50 µm, AM-F-50; 100 µm, AM-F-100], and Denturetec [50 µm, AM-S-50; 100 µm, AM-S-100]) manufactured denture base materials (n = 10). Ra measurements were performed before and after polishing by using a non-contact optical profilometer, while MH values and color coordinates were measured after polishing. Specimens were then subjected to 5000 cycles of coffee thermal cycling, all measurements were repeated, and color differences (ΔE00) were calculated. A linear mixed effect model was used to analyze Ra and MH data, while one-way analysis of variance was used to analyze ΔE00 data (α = 0.05). Ra values were further evaluated according to a clinically acceptable threshold of 0.2 µm, while ΔE00 values were evaluated according to perceptibility (1.72 units) and acceptability (4.08 units) thresholds. The interaction between the material type and the time interval affected both Ra and MH (p ≤ 0.001). Tested materials had their highest Ra before polishing (p ≤ 0.029). Before polishing, AM-F-100 had the highest, and SM-M and SM-G had the lowest Ra (p < 0.001). After polishing and after coffee thermal cycling, SM-G mostly had lower Ra than those of other materials (p ≤ 0.036). SM-G mostly had higher MH than that of other materials before and after coffee thermal cycling (p ≤ 0.025). Coffee thermal cycling reduced the MH of SM-M and increased that of AM-S-100 (p ≤ 0.024). AM-N-100 had higher ΔE00 than AM-F, AM-S-100, and SM-G (p ≤ 0.009), while AM-F and SM-G had lower ΔE00 than AM-S-50 and AM-N-50 (p ≤ 0.024). CONCLUSIONS Polishing reduced the surface roughness of all materials, whereas the effect of coffee thermal cycling was nonsignificant. Most of the tested materials had acceptable surface roughness after polishing and after coffee thermal cycling according to the reported threshold. Layer thickness only affected the microhardness of tested additively manufactured resins, which was material-dependent. Subtractively manufactured specimens mostly had high microhardness and that of nonreinforced subtractively manufactured resin decreased after coffee thermal cycling. When reported color thresholds are considered, all materials had acceptable color stability.
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Affiliation(s)
- Gülce Çakmak
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Nura Watson Asadolahi
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Martin Schimmel
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
- Division of Gerodontology and Removable Prosthodontics, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Pedro Molinero-Mourelle
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Canan Akay
- Department of Prosthodontics, Faculty of Dentistry, Osmangazi University, Eskisehir, Turkey
- Translational Medicine Research and Clinical Center, Osmangazi University, Eskisehir, Turkey
| | - Mustafa Borga Donmez
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
- Department of Prosthodontics, Faculty of Dentistry, Istinye University, İstanbul, Turkey
| | - Burak Yilmaz
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
- Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland
- Division of Restorative and Prosthetic Dentistry, The Ohio State University, Ohio, USA
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Chowdhury D, Mukherjee S, Maity I, Mazumdar P. Surface roughness and microhardness evaluation of composite resin restorations subjected to three different polishing systems immediately and after 24 h: An in vitro study. J Conserv Dent Endod 2023; 26:639-645. [PMID: 38292743 PMCID: PMC10823974 DOI: 10.4103/jcde.jcde_106_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/17/2023] [Accepted: 09/18/2023] [Indexed: 02/01/2024]
Abstract
Background Finishing and polishing of composite resin restorations can be considered two different procedures or two steps of a single procedure. During the finishing procedure, contours are corrected while margins and irregularities are smoothened. The polishing procedures result in the production of a smooth and lustrous finish. Consensus regarding the correct timing for initiating the steps of finishing and polishing after the curing of the composite resins is divided. Some authors support immediate finishing and polishing while other authors support delaying the finishing and polishing procedures. Aim The aim of this study is to evaluate the surface roughness and microhardness of composite resin restoration subjected to finishing and three different polishing systems immediately and after 24 h. Materials and Method Eighty composite resin samples were prepared. A Teflon mold was made which was customized for this study having dimensions of 10-mm diameter and 2-mm depth. For the first group of specimens, Group I (n = 20) the composite resin surface was covered with Mylar Strips which acted as control. The other specimens (n = 60) were prepared without the use of a Mylar strip, followed by curing. For all the samples, curing was done with a light-emitting diode for 40 s each. Eighty light-cured samples were divided equally into 4 groups, each group containing 20 samples (n = 20). Out of the 20 samples, in the second, third, and fourth groups, (Kenda C. G. I., Shofu Super-snap X-Treme, and Eve Diacomp Plus Twist) 10 samples were finished and polished immediately after curing and the other 10 samples were finished and polished after 24 h of curing. The samples in Groups II, III, and IV were subjected to finishing by a 12-fluted tungsten carbide bur and were polished according to the respective manufacturer's instructions. The samples were then subjected to quantitative analysis of surface roughness by a noncontact three-dimensional optical profilometer (Bruker GT-Q; Ettlingen, Germany) and qualitative analysis of surface roughness by a scanning electron microscope (Zeiss EVO 18 Special Edition; Carl-Zeiss-Strasse; Oberkochen Germany) at ×10,000 magnification. The samples were also subjected to Vickers microhardness measurement using a microhardness tester (Leica VMHT 001; Walter UHL GmbH, Germany) under 100 g load over 10 s. Conclusion A. For surface roughness: The samples cured under Mylar strips gave the least surface roughness values (0.25 ± 0.032). Immediate finishing and polishing procedures led to statistically less surface roughness than when finishing and polishing procedures were performed after a delay of 24 h for all polishing systems used B. For microhardness: The samples cured under Mylar strips gave the least microhardness values (57.1 ± 2.03). Delayed finishing and polishing increased microhardness values in all finishing and polishing systems used. Different polishing systems did not have any significant effect on the microhardness values in immediate and delayed finishing and polishing groups.
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Affiliation(s)
- Debkanya Chowdhury
- Department of Conservative Dentistry and Endodontics, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal, India
| | - Sayantan Mukherjee
- Department of Conservative Dentistry and Endodontics, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal, India
| | - Ipsita Maity
- Department of Conservative Dentistry and Endodontics, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal, India
| | - Paromita Mazumdar
- Department of Conservative Dentistry and Endodontics, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal, India
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Matuszak J. Analysis of Geometric Surface Structure and Surface Layer Microhardness of Ti6Al4V Titanium Alloy after Vibratory Shot Peening. Materials (Basel) 2023; 16:6983. [PMID: 37959580 PMCID: PMC10649277 DOI: 10.3390/ma16216983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/27/2023] [Accepted: 10/29/2023] [Indexed: 11/15/2023]
Abstract
This article presents an analysis of the impact of vibratory shot peening on the surface roughness and physical properties of the Ti6Al4V titanium alloy surface layer after milling. The elements of machine parts and structures made of titanium alloys are often exposed to variable loads during operation. Therefore, it is advisable to apply methods that enhance functional properties and increase the durability of interacting components. Increasing the operational durability of such elements can be achieved by vibratory shot peening. Variable amplitudes A = 24; 33; 42; 51; 60 mm and times t = 1; 7; 13; 19; 25 min were applied. It has been demonstrated that it is possible to achieve a threefold reduction in the roughness parameter, Sa = 0.344 µm, compared with milling, Sa = 0.95 µm. An increase in Smr(c) areal material ratio was observed after vibratory shot peening compared with milling. It has been shown that amplitude has a greater impact on the increase in hardening of the surface layer gh compared with time. The highest rate of change in surface roughness and thickness of the hardened layer was achieved at a vibratory shot-peening time of t = 13 min. The greatest thickness of the hardened layer, exceeding 200 µm, was obtained after shot peening with an amplitude of A = 60 mm.
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Affiliation(s)
- Jakub Matuszak
- Department of Production Engineering, Mechanical Engineering Faculty, Lublin University of Technology, Nadbystrzycka 38D, 20-618 Lublin, Poland
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Berladir K, Hovorun T, Ivanov V, Vukelic D, Pavlenko I. Diffusion Nitride Coatings for Heat-Resistant Steels. Materials (Basel) 2023; 16:6877. [PMID: 37959474 PMCID: PMC10648106 DOI: 10.3390/ma16216877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/19/2023] [Accepted: 10/24/2023] [Indexed: 11/15/2023]
Abstract
The effect of ion nitriding and nitriding in a melamine-based powder mixture on the structure and properties of AISI A290C1M steel was studied in the paper. Using ion nitriding made it possible to shorten the technological cycle's duration by 5-6 times compared to two-stage nitriding, optimize the diffusion layer's composition, provide a technologically simple process automation scheme, and improve the quality of nitride coatings. After the proposed mode of ion nitriding, a saturated layer depth of 0.25-0.32 mm, hardness up to 1000 HV, and an increase in wear resistance by 2.17 times were obtained. Using 95% melamine + 5% sodium fluoride during nitriding in a powder mixture significantly simplified the technological process. It did not require additional expensive equipment, which in turn significantly simplified the nitriding process with energy savings. The proposed technology and the composition of the mixture contributed to a significant acceleration of the nitriding process of AISI A290C1M steel, compared to traditional gas nitriding, and to obtain a hardness of the nitride layer of 970 HV and an increase in wear resistance by 2.6 times. A nitriding speed is explained by a significantly higher amount of atomic nitrogen when using melamine instead of ammonia and by the almost simultaneous disintegration of nanodispersed particles when the nitriding temperature was reached. After nitriding in a powder mixture, steel was subject to the slightest wear.
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Affiliation(s)
- Khrystyna Berladir
- Department of Applied Materials Science and Technology of Structural Materials, Faculty of Technical Systems and Energy Efficient Technologies, Sumy State University, 2, Rymskogo-Korsakova St., 40007 Sumy, Ukraine; (K.B.); (T.H.)
- Department of Automobile and Manufacturing Technologies, Technical University of Kosice, 1, Bayerova St., 080 01 Presov, Slovakia
| | - Tetiana Hovorun
- Department of Applied Materials Science and Technology of Structural Materials, Faculty of Technical Systems and Energy Efficient Technologies, Sumy State University, 2, Rymskogo-Korsakova St., 40007 Sumy, Ukraine; (K.B.); (T.H.)
| | - Vitalii Ivanov
- Department of Automobile and Manufacturing Technologies, Technical University of Kosice, 1, Bayerova St., 080 01 Presov, Slovakia
- Department of Manufacturing Engineering, Machines and Tools, Faculty of Technical Systems and Energy Efficient Technologies, Sumy State University, 2, Rymskogo-Korsakova St., 40007 Sumy, Ukraine
| | - Djordje Vukelic
- Department of Production Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovica, 6, 21000 Novi Sad, Serbia;
| | - Ivan Pavlenko
- Department of Computational Mechanics Named after Volodymyr Martsynkovskyy, Faculty of Technical Systems and Energy Efficient Technologies, Sumy State University, 2, Rymskogo-Korsakova St., 40007 Sumy, Ukraine;
- Department of Industrial Engineering and Informatics, Technical University of Kosice, 1, Bayerova St., 080 01 Presov, Slovakia
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Zhao Y, Wang R, Zhang J, Farid MI, Wu W, Yu T. Evolution of CrC x Ceramic Induced by Laser Direct Energy Deposition Multilayered Gradient Ni204-dr60 Coating. Materials (Basel) 2023; 16:6865. [PMID: 37959463 PMCID: PMC10650887 DOI: 10.3390/ma16216865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/07/2023] [Accepted: 10/19/2023] [Indexed: 11/15/2023]
Abstract
The manufacturing process for many large components of machines leads to a difference in their properties and performances based on changes in location. Functionally graded materials can meet these requirements and address the issue of generation and expansion of interface cracks. Ni204-dr60 gradient coatings were successfully fabricated using laser direct energy deposition (LDED). Microstructure mechanism evolution and microhardness of the gradient coating were comprehensively investigated. The change in the precipitated phase at the grain boundary and the intergranular zones resulted in a change in microstructural characteristics and also affected the microhardness distribution. The reinforced phase of the Ni204 → dr60 gradient zone from Ni204 to dr60 gradually precipitated and was rich in Mo and Nb phase, lath-shaped CrCx phase, network-shaped CrCx phase, block shape (Ni, Si) (C, B) phase, block CrCx phase, and block Cr (B, C) phase. The gradient coating thus acts as a potential candidate to effectively solve the problem of crack generation at the interface of dr60 and the substrate.
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Affiliation(s)
- Yu Zhao
- School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China; (Y.Z.); (R.W.); (J.Z.); (M.I.F.)
- Chongqing Research Institute, Jilin University, Chongqing 401133, China
| | - Ruobing Wang
- School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China; (Y.Z.); (R.W.); (J.Z.); (M.I.F.)
| | - Jian Zhang
- School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China; (Y.Z.); (R.W.); (J.Z.); (M.I.F.)
| | - Muhammad Imran Farid
- School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China; (Y.Z.); (R.W.); (J.Z.); (M.I.F.)
| | - Wenzheng Wu
- School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China; (Y.Z.); (R.W.); (J.Z.); (M.I.F.)
- Chongqing Research Institute, Jilin University, Chongqing 401133, China
| | - Tianbiao Yu
- School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China;
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Lin Y, Wei M, Yang G, Liu H, Ye H, Deng C, Zhang L. The Microstructure, Solidification Path, and Microhardness of As-Cast Ni-Al-Cr-Os Alloys in a Ni-Rich Region. Materials (Basel) 2023; 16:6777. [PMID: 37895759 PMCID: PMC10608678 DOI: 10.3390/ma16206777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/13/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023]
Abstract
In this study, nine as-cast Ni-Al-Cr-Os alloys were prepared, and their constituent phases and microstructure were examined using X-ray diffraction and electron probe microanalysis techniques. The solidification paths of all the alloys in a Ni-rich corner were revealed based on a detailed analysis of the as-cast microstructure. The liquidus cube of the quaternary Ni-Al-Cr-Os system in a Ni-rich corner was established accordingly. A eutectic-type invariant reaction on the liquidus surface was explicitly identified, and its reaction can be expressed as L → α + β + γ. No quaternary invariant reaction was found in the alloys following the addition of Os. The Ni-Al-Cr-Os alloy points were then vertically mapped onto the Ni-Al-Cr liquid phase projection to better observe the effect of Os addition on the solidification path of the Ni-Al-Cr system. It was found that the addition of a small amount of Os has no significant effect on the solidification path of the Ni-Al-Cr system. Furthermore, the microhardness of each alloy, which was determined to be in the range of 207 HV to 565 HV, was found to be closely related to the phase constitution and phase fraction of the alloy.
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Affiliation(s)
- Yan Lin
- State Key Laboratory of Porous Metal Materials, Northwest Institute for Non-Ferrous Metal Research, Xi'an 710016, China
| | - Ming Wei
- State Key Laboratory of Porous Metal Materials, Northwest Institute for Non-Ferrous Metal Research, Xi'an 710016, China
| | - Guangyu Yang
- State Key Laboratory of Porous Metal Materials, Northwest Institute for Non-Ferrous Metal Research, Xi'an 710016, China
| | - Haiyan Liu
- State Key Laboratory of Porous Metal Materials, Northwest Institute for Non-Ferrous Metal Research, Xi'an 710016, China
| | - Hui Ye
- State Key Laboratory of Porous Metal Materials, Northwest Institute for Non-Ferrous Metal Research, Xi'an 710016, China
| | - Chunming Deng
- Institute of New Materials, Guangdong Academy of Sciences, National Engineering Laboratory for Modern Materials Surface Engineering Technology, The Key Lab of Guangdong for Modern Surface Engineering Technology, Guangzhou 510651, China
| | - Lijun Zhang
- State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China
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Shi C, Zhao R, Wang W. Effect of Mud Powder on the Performance of Bridge Deck Leveling Concrete in a Seasonally Frozen Region. Materials (Basel) 2023; 16:6793. [PMID: 37895774 PMCID: PMC10608763 DOI: 10.3390/ma16206793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/14/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023]
Abstract
Mud powders in aggregates are often found to cause deterioration of concrete properties. Based on a study of the mechanical properties of bridge deck leveling concrete (BDLC) containing different mud powders at various ages, the effects of mud powders on concrete durability were evaluated through rapid chloride permeability testing, freeze-thaw testing, and the coupling of salt solution and a freeze-thaw test. The properties of the interfacial transition zone (ITZ) were also investigated via microhardness testing. The test results showed that mud powder reduced the compressive strength, static compressive elastic modulus, and bond strength at early stages of curing. Moreover, mud powder was found to reduce the tensile properties and durability of concrete, with clay powder causing a greater reduction than mud powder in river sands and coarse aggregate. In addition, the width of the ITZ of concrete containing mud powder was found to increase by 23.1-48.3%. A significant correlation between the ITZ and the tensile properties, as well as the durability of concrete, was also observed. Therefore, in order to improve the tensile properties and durability of BDLC in seasonally frozen regions, the content of mud powder in the aggregates should be minimized according to the different compositions of mud powders. The coupling effect of salt solution and a freeze-thaw cycle should also be taken into consideration.
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Affiliation(s)
- Chenglin Shi
- College of Transportation Science and Engineering, Jilin Jianzhu University, Changchun 130118, China
- Kay Laboratory of Architectural Cold Climate Energy Management, Ministry of Education, Changchun 130118, China
| | - Ruize Zhao
- Kay Laboratory of Architectural Cold Climate Energy Management, Ministry of Education, Changchun 130118, China
| | - Wensheng Wang
- College of Transportation, Jilin University, Changchun 130022, China
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Naik GM, Sharma P, Anne G, Pittala RK, Kumar R, Satapathi GS, Kumar CS, Fernandes F. Improvement in Corrosion Performance of ECAPed AZ80/91 Mg Alloys Using SS316 HVOF Coating. Materials (Basel) 2023; 16:6651. [PMID: 37895635 PMCID: PMC10608680 DOI: 10.3390/ma16206651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 09/29/2023] [Accepted: 10/07/2023] [Indexed: 10/29/2023]
Abstract
Mg AZ80/91 alloys are highly popular due to their lightweight, high strength-to-weight ratio, and good machinability. However, their moderate mechanical properties and corrosion resistance have limited their use in the automotive, aerospace, and defense sectors. This study primarily aims to enhance the mechanical performance and corrosion resistance of Mg AZ80/91 alloys, making them more suitable for applications in the aerospace and automotive industries. Firstly, equal-channel angular pressing (ECAP) of Mg AZ80/91 alloys has been attempted to improve their mechanical properties. Secondly, a high-velocity oxy-fuel (HVOF) coating of SS316 was applied over the Mg AZ80/91 substrate to enhance its corrosion resistance. In the second step, an HVOF coating of SS316 is applied over the Mg AZ80/91 substrate for better corrosion resistance. The experimental findings demonstrate that the application of an SS316 coating on the ECAP-4P AZ80/91 Mg alloy substrate results in a uniform and dense layer with an average thickness of approximately 80 ± 5 µm. The HVOF-based SS316 coating on 4P-ECAP leads to a noteworthy enhancement in microhardness and a reduction in the corrosion rate, especially in a NaCl solution (3.5 wt.%). This improvement holds great promise for producing reliable, long-lasting, and resilient automotive, aerospace, and defense components. The application of an HVOF-based SS316 coating onto the AZ80 Mg alloy, which had not undergone ECAP treatment, led to a substantial enhancement in corrosion resistance. This resulted in a notable decrease in the corrosion current density, reducing it from 0.297 mA/cm2 to 0.10 µA/cm2.
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Affiliation(s)
- Gajanan M. Naik
- Department Mechanical Engineering, RV Institute of Technology and Management, Bengaluru 5680076, Karnataka, India;
| | - Priyaranjan Sharma
- Department of Mechanical Engineering, Koneru Lakshmaiah Education Foundation, Vijayawada 522502, Andhra Pradesh, India
| | - Gajanan Anne
- Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Raj Kumar Pittala
- Department of Mechanical Engineering, Koneru Lakshmaiah Education Foundation, Vijayawada 522502, Andhra Pradesh, India
| | - Rahul Kumar
- Department of Mechanical Engineering, School of Engineering and Technology, Sandip University, Nashik 422213, Maharashtra, India
| | - Gnane Swarnadh Satapathi
- Department of Electronics and Communication Engineering, A J Institute of Engineering and Technology, Mangaluru 575006, Karnataka, India
| | - Ch Sateesh Kumar
- CFAA-Aeronautics Advanced Manufacturing Center, University of the Basque Country (UPV/EHU), Biscay Science and Technology Park, 48170 Zamudio, Spain
- Department of Mechanical Engineering, University of the Basque Country, Escuela Superior de Ingenieros Alameda de Urquijo S/N, 48013 Bilbao, Spain
| | - Filipe Fernandes
- University of Coimbra, CEMMPRE, ARISE, Department of Mechanical Engineering, Rua Luís Reis Santos, 3030-788 Coimbra, Portugal;
- ISEP, Polytechnic of Porto, Rua Dr. António Bernardino de Almeida, 4249-015 Porto, Portugal
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Zhao X, Qiu L, Kong D, Huang Y, Liu J. Effects of Three-Dimensional Graphene-Carbon Nanotube Hybrid on the Mechanical Properties and Microstructure of Cement Paste. Materials (Basel) 2023; 16:6571. [PMID: 37834708 PMCID: PMC10573913 DOI: 10.3390/ma16196571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 09/17/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023]
Abstract
This work experimentally studies the mechanical properties and microstructure of cementitious composites reinforced with a three-dimensional graphene-carbon nanotube (CNT) hybrid. Firstly, the graphene-CNT (GC) hybrid is dispersed in cement pastes using ultrasonication and surfactant, and then, the effect of the GC hybrid on the early hydration of the cement pastes is investigated. The experimental results show that adding the GC hybrid shortens the setting stage of cement hydration and accelerates the early hydration process. Moreover, the macro- and micro-mechanical properties of each group are evaluated. The 7- and 28-day strength of the cement pastes improves with addition of the GC hybrid. Finally, the microstructural analysis demonstrates that the GC hybrid is reasonably well distributed in cement and forms a spatial network, which could bridge the cracks and compact the cementitious matrix.
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Affiliation(s)
- Xin Zhao
- Department Disaster Mitigation Structure, College of Civil Engineering, Tongji University, Shanghai 200092, China;
- College of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou 310018, China
| | - Li Qiu
- China Railway Eryuan Engineering Group, East China Survey and Design Co., Ltd., Hangzhou 310009, China;
| | - Deyu Kong
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310018, China;
| | - Yangfei Huang
- College of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou 310018, China
| | - Jintao Liu
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310018, China;
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Maciel JLB, Geng Vivanco R, Pires-de-Souza FDCP. Remineralization, color stability and surface roughness of tooth enamel brushed with activated charcoal-based products. J ESTHET RESTOR DENT 2023; 35:1144-1151. [PMID: 37083113 DOI: 10.1111/jerd.13057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/29/2023] [Accepted: 04/11/2023] [Indexed: 04/22/2023]
Abstract
OBJECTIVE To evaluate the effect of activated charcoal-based (AC) products on color alteration, remineralizing potential and surface roughness of dental enamel. MATERIALS AND METHODS Bovine incisors were cut into 6 × 6 × 2 mm fragments. Initial color (EasyShade, Vita) and surface roughness (Surfcorder SE1700, Kosakalab) readings were performed. Fragments were separated into five groups (n = 17) according to the treatment: Control: Fluoride toothpaste (Colgate Total 12, Colgate); Charcoal + NaF: AC toothpaste (ACT) with sodium fluoride (Colgate Natural Extracts, Colgate); Charcoal + MFP + n-HA: ACT with sodium monofluorophosphate and nanohydroxyapatite (Black is White, Curaprox); Charcoal: Fluoride-free ACT (ProActive, Hinode); and Charcoal powder: AC powder. Simulated toothbrushing was performed and final color and surface roughness readings were obtained. Fragments were then polished, and initial microhardness (HMV-2, Shimatzu) readings were done. Samples were artificially demineralized and brushed again. Final microhardness readings were taken. Data were statistically analyzed. RESULTS Fluoride-free charcoal presented the lowest surface roughness alteration (p < 0.05). Charcoal powder had the lowest color change (p < 0.05) and negative values for whiteness index for dentistry alteration. All the groups presented values below whiteness acceptability threshold and negative relative microhardness values. Control showed the highest remineralizing potential (p < 0.05). CONCLUSIONS ACPs did not produce color alteration different from the fluoride toothpaste, except for Charcoal powder that caused less color change. ACPs caused surface roughness alteration similar to the fluoride toothpaste. ACT with fluoride and AC powder did not have remineralizing potential. CLINICAL SIGNIFICANCE Activated charcoal-based products (ACP) promise effective tooth whitening and quick results, without teeth damage. In addition, some ACPs contain fluoride in toothpaste composition and promise rehardening potential. However, ACPs are not as effective as other whitening agents and can alter the surface roughness of the enamel. Even if the ACPs contain fluoride or other remineralizing agents, they might be ineffective.
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Affiliation(s)
- João Lucas Borim Maciel
- Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Rocio Geng Vivanco
- Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil
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Bhopatkar J, Ikhar A, Chandak M, Patel A, Agrawal P. Examining the Impact of Preheating on the Fracture Toughness and Microhardness of Composite Resin: A Systematic Review. Cureus 2023; 15:e47117. [PMID: 38022172 PMCID: PMC10647940 DOI: 10.7759/cureus.47117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
The objective of this comprehensive study was to systematically evaluate the effects of preheating on two critical mechanical properties, microhardness and fracture toughness, in resin composite materials. The overarching goal was to provide valuable insights into the potential benefits and limitations of this technique for enhancing the overall mechanical performance of such materials. To achieve this, an extensive and systematic electronic search was conducted across multiple reputable databases, including MEDLINE/PubMed, SCOPUS, ProQuest, SpringerLink, Web of Science, ScienceDirect, and Google Scholar, with data collection extending until June 2023. This rigorous search process resulted in the identification of 29 pertinent articles, which were subjected to a thorough risk of bias assessment employing the Quality Assessment Tool For In Vitro Studies (QUIN). The findings of this comprehensive investigation revealed several noteworthy trends. First, concerning microhardness, all the studies consistently demonstrated a positive effect of preheating on this mechanical property. This uniformity in results corroborates the initial hypothesis that preheating indeed enhances microhardness in resin composite materials. Second, with respect to fracture toughness, a majority of the studies provided evidence supporting the notion that preheating has a favorable influence on this particular mechanical property. This alignment of outcomes suggests that preheating can be a beneficial technique for improving fracture toughness in resin composites. However, it is essential to note that there were a few exceptions within the collected data, where preheating appeared to lead to a decrease in fracture toughness. Additionally, one study reported no statistically significant effect on fracture toughness. These deviations from the general trend highlight the complexity of the relationship between preheating and fracture toughness, indicating that other factors or material-specific nuances may come into play. In conclusion, the results of this study indicate that preheating resin composites can improve microhardness and fracture toughness, offering potential benefits for dental restorations. Yet, conflicting data warrants further research to uncover the reasons behind these discrepancies. Future studies should also investigate preheating's broader impact on composite resin materials to gain a comprehensive understanding of its applications and limitations in the field.
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Affiliation(s)
- Jay Bhopatkar
- Department of Conservative Dentistry and Endodontics, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Anuja Ikhar
- Department of Conservative Dentistry and Endodontics, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Manoj Chandak
- Department of Conservative Dentistry and Endodontics, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Aditya Patel
- Department of Conservative Dentistry and Endodontics, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Paridhi Agrawal
- Department of Conservative Dentistry and Endodontics, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research, Wardha, IND
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Pavlov A, Sagdoldina Z, Zhilkashinova A, Magazov N, Turar Z, Gert S. Synthesis and Investigation of Properties of Beryllium Ceramics Modified with Titanium Dioxide Nanoparticles. Materials (Basel) 2023; 16:6507. [PMID: 37834644 PMCID: PMC10573473 DOI: 10.3390/ma16196507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/17/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023]
Abstract
Samples of beryllium ceramics, with the addition of micro- and nanoparticles TiO2, have been obtained by the method of thermoplastic slip casting. The microstructure of batch ceramics, consisting of micropowders and ceramics with TiO2 nanoparticles sintered at an elevated temperature, has been investigated. It was found that the introduction of TiO2 nanoparticles leads to changes in the mechanisms of mass transfer and microstructure formation, and the mobility of TiO2 at interfacial grain boundaries increases, which leads to the formation of elements of a zonal shell structure. The reduction of intergranular boundaries leads to an increase in density, hardness, and mechanical strength of ceramics. The whole complex of properties of the synthesized material, with the addition of TiO2 nanoparticles in the amount of 1.0-1.5 wt.%, leads to an increase in the ability to absorb electromagnetic radiation in the frequency range of electric current 8.2-12.4 GHz. The analysis and updating of knowledge on synthesis, and the investigation of properties of beryllium ceramics modified by nanoparticles, seems to be significant. The obtained results can be used in the creation of absorbers of scattered microwave radiation based on (BeO + TiO2) ceramics.
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Affiliation(s)
- Alexandr Pavlov
- Surface Engineering and Tribology Research Center, Sarsen Amanzholov East-Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan
| | - Zhuldyz Sagdoldina
- Surface Engineering and Tribology Research Center, Sarsen Amanzholov East-Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan
| | - Almira Zhilkashinova
- National Laboratory of Collective Use, Sarsen Amanzholov East-Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan
| | - Nurtoleu Magazov
- Surface Engineering and Tribology Research Center, Sarsen Amanzholov East-Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan
- Center of Excellence “VERITAS”, Daulet Serikbayev East Kazakhstan Technical University, Ust-Kamenogorsk 070000, Kazakhstan
| | - Zhangabay Turar
- Surface Engineering and Tribology Research Center, Sarsen Amanzholov East-Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan
| | - Sergey Gert
- Center of Excellence “VERITAS”, Daulet Serikbayev East Kazakhstan Technical University, Ust-Kamenogorsk 070000, Kazakhstan
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Skoczylas A, Kłonica M. Selected Properties of the Surface Layer of C45 Steel Samples after Slide Burnishing. Materials (Basel) 2023; 16:6513. [PMID: 37834649 PMCID: PMC10573627 DOI: 10.3390/ma16196513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/15/2023]
Abstract
This paper presents the experimental results of a study investigating the impact of the machining fluid type, the variable factor, used in slide burnishing on 2D and 3D surface roughness; surface topography; Abbott-Firestone curve shape; microhardness; and SFE (surface free energy). In the experiment, pre-ground, ringed samples of C45 steel were used. The results showed an over eight-fold decrease in the value of the Ra (arithmetical mean deviation) parameter and over a five-fold decrease in the Rt (total height of profile) parameter in relation to their values after grinding. The parameters Rpk (reduced peak height), Rk (core roughness depth), and Rvk (reduced valley depth) were also reduced. The Abbott-Firestone curve after slide burnishing changed its angle of inclination (it was more flattened), and the material ratio Smr increased. The reduction in the Rpk and Rk parameters and increased material ratio will most likely contribute to restoring the functionality of these surfaces (increased resistance to abrasive wear). After slide burnishing, the maximum 25% increase in microhardness was obtained compared to the value after grinding, while the layer thickness was 20 μm. The surface energy of elements subjected to slide burnishing using various machining fluids slightly increased, or its value was close to that of the ground surface. The most favourable properties of the surface layer in terms of mating between two elements were obtained for a part that was slide-burnished with a mixture of oil + polymethyl methacrylate (PMM) + molybdenum disulphide (MoS2).
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Affiliation(s)
- Agnieszka Skoczylas
- Department of Production Engineering, Mechanical Engineering Faculty, Lublin University of Technology, 20-618 Lublin, Poland;
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Nikolaeva N, Rozanov V, Chernyaev A, Matveychuk I, Makarova M. The Influence of Combined Sterilization Factors on the Structural and Functional Characteristics of Bone Implants. Int J Mol Sci 2023; 24:14426. [PMID: 37833874 PMCID: PMC10573022 DOI: 10.3390/ijms241914426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 10/15/2023] Open
Abstract
The results of a comprehensive study of the patterns of structural and functional changes in bone tissue samples after combined (ozone + radiation) sterilization are presented. The study used a different approach to the sterilization process with selective ozone or radiation exposure and an integral, combined one, based on a combined ozone-oxygen treatment of bone samples at the first stage and radiation at the second. The methods of IR spectroscopy, scanning electron microscopy with a prefix for elemental analysis, atomic force microscopy, and mechanical analysis with determination of elastic-plastic properties (Vickers microhardness index) were used in the work. It is shown that the ozone exposure used at the first stage of the combined sterilization process of bone implants does not lead to negative consequences with respect to their properties and characteristics. The results obtained serve as a scientific and methodological basis for the further improvement and optimization of sterilization technologies (including combined). They also offer a comprehensive justification of the parameters of sterilization regimes to ensure the safety of using bone implants during reconstructive operations, minimizing structural and functional changes in bone matter, and creating effective health-saving technologies and the possibility of using them for various biomedical applications.
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Affiliation(s)
- Nadezhda Nikolaeva
- Radiation Technologies Laboratory, Institute of Physics and Technology, M.K. Ammosov North-Eastern Federal University, 677000 Yakutsk, Russia; (N.N.); (A.C.)
| | - Vladimir Rozanov
- Radiation Technologies Laboratory, Institute of Physics and Technology, M.K. Ammosov North-Eastern Federal University, 677000 Yakutsk, Russia; (N.N.); (A.C.)
- Physical Faculty, Lomonosov Moscow State University, 119991 Moscow, Russia
- Scientific and Educational-Methodical Center of Biomedical Technology, The All-Russian Research Institute of Medicinal and Aromatic Plants, 117216 Moscow, Russia;
| | - Alexander Chernyaev
- Radiation Technologies Laboratory, Institute of Physics and Technology, M.K. Ammosov North-Eastern Federal University, 677000 Yakutsk, Russia; (N.N.); (A.C.)
- Physical Faculty, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Igor Matveychuk
- Scientific and Educational-Methodical Center of Biomedical Technology, The All-Russian Research Institute of Medicinal and Aromatic Plants, 117216 Moscow, Russia;
| | - Milena Makarova
- Radiation Technologies Laboratory, Institute of Physics and Technology, M.K. Ammosov North-Eastern Federal University, 677000 Yakutsk, Russia; (N.N.); (A.C.)
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Feldshtein E, Devojno O, Patalas-Maliszewska J, Kardapolava M, Kasiakova I. On the Efficiency of Laser Alloying of Grey Cast Iron with Tungsten and Silicon Carbides. Materials (Basel) 2023; 16:6230. [PMID: 37763508 PMCID: PMC10532839 DOI: 10.3390/ma16186230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/09/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023]
Abstract
Cast iron is widely used in engineering production and in the surface alloying of workpieces, which is exploited to improve the properties of the material. Research on cast iron is still valid and needed for the manufacturing processes throughout the product life cycle. In this study, the gray, cast iron GJL 200 laser processing is described based on surface alloying with WC and SiC particulates. SEM analysis and XRD analysis, as well as microhardness testing and tribological behavior studies, were employed. It was revealed that laser alloying with carbide particulates affects structural, mechanical, and operational properties compared to cast iron in its initial state. Most importantly, the right choice of laser processing conditions can increase the wear resistance of the cast iron base. The wear resistance after WC alloying was 4-24 times higher compared to the initial material, while after SiC alloying, it was 2-18 times lower than that of the initial material.
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Affiliation(s)
- Eugene Feldshtein
- Institute of Mechanical Engineering, University of Zielona Góra, Prof. Z. Szafrana 4, 65-516 Zielona Góra, Poland;
| | - Oleg Devojno
- Faculty of Mechanical Engineering, Belarusian National Technical University, Khmelnitsky Str., 9, Build. 6, 220013 Minsk, Belarus; (O.D.); (M.K.); (I.K.)
| | - Justyna Patalas-Maliszewska
- Institute of Mechanical Engineering, University of Zielona Góra, Prof. Z. Szafrana 4, 65-516 Zielona Góra, Poland;
| | - Marharyta Kardapolava
- Faculty of Mechanical Engineering, Belarusian National Technical University, Khmelnitsky Str., 9, Build. 6, 220013 Minsk, Belarus; (O.D.); (M.K.); (I.K.)
| | - Iryna Kasiakova
- Faculty of Mechanical Engineering, Belarusian National Technical University, Khmelnitsky Str., 9, Build. 6, 220013 Minsk, Belarus; (O.D.); (M.K.); (I.K.)
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Tseluikin V, Dzhumieva A, Yakovlev A, Tikhonov D, Tribis A, Strilets A, Lopukhova M. Electrodeposition and Properties of Composite Ni Coatings Modified with Multilayer Graphene Oxide. Micromachines (Basel) 2023; 14:1747. [PMID: 37763910 PMCID: PMC10537176 DOI: 10.3390/mi14091747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 09/02/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023]
Abstract
Within the framework of this study, Ni-based composite electrochemical coatings (CECs) modified with multilayer graphene oxide (GO) processed using microwave radiation have been deposited. The process of these coatings' electrodeposition in the potentiodynamic mode has been studied. The structure of Ni-GO and Ni-GO (MW) CECs has been studied using X-ray phase analysis (XPA) and scanning electron microscopy (SEM).It has been shown that the addition of GO into a nickel deposit contributes to the formation of uniform fine-grained coatings. As a result, the microhardness of the Ni-GO (MW) CECs increases by 1.40 times compared to Ni without GO. The corrosion-electrochemical behavior of nickel CECs in 0.5 M H2SO4 solution was researched. It was established that the corrosion rate of the nickel-GO (MW) CEC in 3.5% NaCl decreases by about 1.70 times in contrast to unmodified nickel coatings. This effect is due to the absence of agglomeration of the graphene oxide in the volume of the nickel matrix and the impermeability of GO particles to the corrosive environment.
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Affiliation(s)
- Vitaly Tseluikin
- Engels Technological Institute, Yuri Gagarin State Technical University of Saratov, Polytechnichskaya St., 77, 410054 Saratov, Russia; (A.D.); (A.Y.); (D.T.); (A.T.); (A.S.); (M.L.)
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Lakshmaiah D, Irudayaraj N, Ambeth N, Ramachandran A, Sakthi N, Kumar N. Comparative Evaluation of Microhardness, Smear Layer Removal Efficacy and Depth of Penetration Using Punica granatum, Emblica officinalis and Sodium Hypochlorite As Endodontic Irrigants: An In Vitro Study. Cureus 2023; 15:e44760. [PMID: 37809222 PMCID: PMC10556994 DOI: 10.7759/cureus.44760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/06/2023] [Indexed: 10/10/2023] Open
Abstract
Introduction Root canal morphology tends to be complicated by nature and dealing with this intricacy can be challenging because it makes it difficult to completely disinfect the root canal space. The success of root canal therapy is also determined by the biomechanical preparation of the canal with the application of instruments and irrigating solutions. Due to the fact that the root dentin surface continues to interact with the irrigating solution during preparation, it's critical to evaluate the mechanical characteristics and smear layer removal. Though sodium hypochlorite (NaOCl) is the most commonly used irrigant due to its tissue-dissolving abilities, it has certain drawbacks which include the inability to remove the smear layer and also affects the mechanical properties of root dentin. To overcome these limitations, a variety of herbal substitutes like Punica granatum and Emblica officinalis which possess anti-bacterial and anti-fungal properties can be used as endodontic irrigants. Several studies on the anti-bacterial properties of natural irrigants of pomegranate and amla were reported. However, the mechanical properties and smear layer removal of Punica granatum and Emblica officinalis have not been explored in the field of endodontics. Aim The main aim of this in vitro study is to compare and evaluate microhardness, smear layer removal efficacy and depth of penetration of herbal and conventional irrigants. Materials and methods Thirty-six palatal roots of maxillary molars were decoronated and instrumented up to F3. These roots were sectioned longitudinally and divided into three test groups: Group 1: 12.5% Punica granatum; Group 2: 6.25% Emblica officinalis; control: Group 3: 2.5% NaOCl. All specimens were irrigated with 5ml of each irrigant for 5 minutes. Microhardness of root dentin was measured using a Vickers diamond intender, smear layer removal using a scanning electron microscope (SEM) and depth of penetration using a stereomicroscope. The data was analyzed using one-way ANOVA and the inter-group comparison using Tukey's post hoc test. Results Statistical analysis was done using one-way analysis of variance (ANOVA) and Tukey's post hoc test using SPSS software version 17.0 (SPSS Inc., Chicago ). The highest microhardness was seen in Group 1 (cervical: 53.8375 ± 1.35956, middle: 53.9875 ± 1.01761, apical: 53.6875 ± 1.63133) while Group 2 (cervical: 43.2750 ± 1.73596, middle: 43.3125 ± 1.17648, apical: 43.8000 ± 1.32665) and Group 3 (cervical: 42.7250 ± 2.93391, middle: 41.9625 ± 1.66985, apical: 42.0250 ± 2.21085) showed significant reduction in root dentin hardness. Regarding smear layer removal Group 1 (1.3750 ± 0.51755), and Group 2 (1.2500 ± 0.46291) reveals greater smear removal in the middle third of the root dentin compared with Group 3 (2.3750 ± 0.51755), which showed the least smear layer removal. A greater depth of penetration was seen in Group 1 (0.5488 ± 0.05222) and Group 2 (0.5263 ± 0.05181) than in Group 3 (0.3087 ± 0.05743). Conclusion The present study reveals that the least reduction of microhardness was seen in Punica granatum followed by Emblica officinalis and NaOCl. The smear layer removal efficacy and depth of penetration were greater in Punica granatum and Emblica officinalis than in NaOCl. It was concluded that as these herbal irrigants are biocompatible agents, they can be considered for future use in root canal treatment.
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Affiliation(s)
- Deepika Lakshmaiah
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Nancy Irudayaraj
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Nivetha Ambeth
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Anupama Ramachandran
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Nikesh Sakthi
- Department of Conservative Dentistry and Endodontics, Chettinad Dental College and Research Institute, Chennai, IND
| | - Nirmal Kumar
- Department of Conservative Dentistry and Endodontics, Ragas Dental College and Hospital, Chennai, IND
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Torsakul P, Rirattanapong P, Prapansilp W. The Remineralization Effect of Calcium Glycerophosphate in Fluoride Mouth Rinse on Demineralized Primary Enamel: An in vitro Study. J Int Soc Prev Community Dent 2023; 13:410-415. [PMID: 38124723 PMCID: PMC10729885 DOI: 10.4103/jispcd.jispcd_114_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 09/22/2023] [Accepted: 09/22/2023] [Indexed: 12/23/2023] Open
Abstract
Aim To evaluate the remineralization effect of a fluoride mouth rinse containing calcium glycerophosphate in fluoride mouth rinse based on the surface microhardness of demineralized primary enamel. Materials and Methods 40 sound primary incisors were placed into self-curing acrylic resin and subjected to a demineralizing solution for 5 days, resulting in the formation of artificial caries. The teeth were categorized into four groups (n = 10): group I artificial saliva, group II sodium fluoride, group III sodium fluoride + sodium monofluorophosphate, and group IV sodium monofluorophosphate + calcium glycerophosphate. The specimens received a pH cycling procedure and were submerged twice in their assigned groups for 7 days. The baseline, after demineralization, and after remineralization surface microhardness values were determined. One-way analysis of variance (ANOVA) was used to analyze the mean surface microhardness between groups and one-way repeated measures ANOVA for the mean surface microhardness within each group and Bonferroni's for multiple comparisons at 95% confidence level. The percentage recovery surface microhardness was determined by calculating the average surface microhardness. Results After demineralization, the mean surface microhardness in all groups significantly decreased. After remineralization, group I had the lowest surface microhardness values and the percentage recovery surface microhardness (P value < 0.001), and group IV had the highest surface microhardness values and the percentage recovery surface microhardness (P value < 0.001). No significant difference was found between groups II and III (P value = 0.365). Conclusions Fluoride mouth rinse containing calcium glycerophosphate has a remineralization effect on demineralized primary enamel.
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Affiliation(s)
- Pannaros Torsakul
- Department of Pediatric Dentistry, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Praphasri Rirattanapong
- Department of Pediatric Dentistry, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Woranun Prapansilp
- Department of Pediatric Dentistry, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
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Alessa NA. Effect of mouthwashes on the microhardness of aesthetic composite restorative materials. An Sist Sanit Navar 2023; 46:e1049. [PMID: 37647204 PMCID: PMC10520749 DOI: 10.23938/assn.1049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/11/2023] [Accepted: 07/21/2023] [Indexed: 09/01/2023]
Abstract
BACKGROUND Mouthwashes are increasingly being used worldwide. However, these preparations are known to have a negative impact on composite resin dental restorations. In this study, we aim to evaluate the effect of mouthwashes on the microhardness of such restorations. METHODS Thirty specimens of Tetric N-Ceram composite were prepared. Each composite specimen was cured for 40 seconds and kept in saline solution for 24 hours at 37 °C. Baseline microhardness of each specimen was recorded using an Innovatest Vickers Micro Hardness Tester. Composite specimens were randomly placed in 20 mL of the selected mouthwashes (Colgate® Plax, Listerine® Teeth & Gum Defence, and Closeup® Antibacterial Mouthwash Cool Breeze) and stored in an incubator for 24 hours at 37 °C. Next, microhardness values were rechecked. pH measurements were recorded for each type of mouthwash using a digital pH meter. RESULTS Due to the acidic nature of Colgate® and Listerine®, the microhardness of the restorations decreased with these mouthwashes; Listerine® caused the greatest decrease in microhardness and had the lowest pH reading (4.34). For Closeup®, with a neutral pH (7.02), no negative effect on microhardness was found; on the contrary, due to the presence of zinc in this latter mouthwash, an increase of the microhardness was found. CONCLUSIONS We confirm the negative effect of acidic mouthwashes on the microhardness of composite dental restorations.
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Skakov M, Bayandinova M, Ocheredko I, Tuyakbayev B, Nurizinova M, Gradoboev A. Influence of Diabase Filler on the Structure and Tribological Properties of Coatings Based on Ultrahigh Molecular Weight Polyethylene. Polymers (Basel) 2023; 15:3465. [PMID: 37631522 PMCID: PMC10458548 DOI: 10.3390/polym15163465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
This article presents the results of a study of a composite coating made of ultrahigh molecular weight polyethylene (UHMWPE) with a diabase filler obtained by flame spraying. Diabase of 10 wt.%, 20 wt.%, 30 wt.% and 40 wt.% was chosen as a filler. The polymer coating was applied to the St3 metal substrate using temperature control in a conventional flame spraying process. The coating was studied using scanning electron microscopy, X-ray phase analysis, infrared spectroscopy, abrasive wear resistance, microhardness testing and determination of the friction coefficient. It has been shown that diabases do not have a negative effect on the initial chemical structure of UHMWPE and it is not subjected to destruction during flame spraying. The introduction of diabase into the composition of UHMWPE with a content of 10-40% of the total mass does not adversely affect the crystalline structure of the coating. It has been established that with an increase in the volume of the diabase filler, the wear resistance of the composite coating based on UHMWPE increases. It has been determined that with the addition of diabase, the microhardness of the coatings increases.
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Affiliation(s)
- Mazhyn Skakov
- National Nuclear Center of the Republic of Kazakhstan, Ministry of Energy of the Republic of Kazakhstan, Kurchatov 071100, Kazakhstan;
- National Scientific Laboratory of Collective Use, Sarsen Amanzholov East Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan; (I.O.); (B.T.); (M.N.)
| | - Moldir Bayandinova
- National Scientific Laboratory of Collective Use, Sarsen Amanzholov East Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan; (I.O.); (B.T.); (M.N.)
| | - Igor Ocheredko
- National Scientific Laboratory of Collective Use, Sarsen Amanzholov East Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan; (I.O.); (B.T.); (M.N.)
| | - Baurzhan Tuyakbayev
- National Scientific Laboratory of Collective Use, Sarsen Amanzholov East Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan; (I.O.); (B.T.); (M.N.)
| | - Makpal Nurizinova
- National Scientific Laboratory of Collective Use, Sarsen Amanzholov East Kazakhstan University, Ust-Kamenogorsk 070000, Kazakhstan; (I.O.); (B.T.); (M.N.)
| | - Alexander Gradoboev
- Experimental Physics Department, Tomsk Polytechnic University, Tomsk 634050, Russia;
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Żaba K, Trzepieciński T. Cold Drawing of AISI 321 Stainless Steel Thin-Walled Seamless Tubes on a Floating Plug. Materials (Basel) 2023; 16:5684. [PMID: 37629975 PMCID: PMC10456630 DOI: 10.3390/ma16165684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 08/14/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023]
Abstract
The paper presents the results of an analysis of the process of drawing AISI 321 stainless steel thin-walled seamless tubes on a floating plug. The influence of the geometry of dies and plugs, drawing velocity, and lubricants on the possibility of carrying out the pipe drawing process without a loss of strength of the lubricating film and, consequently, disturbance of the forming process and tube cracking, and also on the temperature in the drawing process, the mechanical properties of the tubes drawn, and the microhardness and roughness of the inner and outer surface of the tubes was investigated. The parameters of the drawing tools used were as follows: angle of drawing dies α = 16° and floating plugs with angles of inclination of the conical part of the plug β = 11.5°, 13°, and 14°. The drawing dies and floating plugs were made of G10 sintered carbide. Drawing speed was varied over the range 1 to 10 m/min. The study used several lubricants. Tubes with dimensions (outer diameter D0, wall thickness g0 before drawing process) D0 = 19 mm, g0 = 1.2 mm and D0 = 18 mm, g0 = 1.2 mm were drawn to produce tubes with dimensions (outer diameter Dk, wall thickness gk after drawing process) Dk = 16 mm, gk = 1.06 mm on a drawbench with the same total elongation, while the diameter and wall thickness were changed. During the process, continuous measurements were made of the drawing force and temperature in the deformation zone and on the tube surface. It was found that the drawing process causes a decrease in the roughness parameters Ra and Rz of the inner surface of the tubes. Moreover, after drawing, an increase of 30-70% was observed in the microhardness of the tube material in relation to the microhardness of the charge material. Based on the test results, it can be concluded that the work of frictional forces is the main direction of optimization of tube drawing on a floating plug process of hard-deforming materials.
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Affiliation(s)
- Krzysztof Żaba
- Department of Metal Working and Physical Metallurgy of Non-Ferrous Metals, Faculty of Non-Ferrous Metals, AGH—University of Science and Technology, al. Adama Mickiewicza 30, 30-059 Cracow, Poland
| | - Tomasz Trzepieciński
- Department of Manufacturing Processes and Production Engineering, Faculty of Mechanical Engineering and Aeronautics, Rzeszow University of Technology, al. Powst. Warszawy 8, 35-959 Rzeszów, Poland
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