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Maleki T, Meinen J, Coldea A, Reymus M, Edelhoff D, Stawarczyk B. Mechanical and physical properties of splint materials for oral appliances produced by additive, subtractive and conventional manufacturing. Dent Mater 2024; 40:1171-1183. [PMID: 38851965 DOI: 10.1016/j.dental.2024.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 03/15/2024] [Accepted: 05/29/2024] [Indexed: 06/10/2024]
Abstract
OBJECTIVES To investigate the flexural strength (FS), elastic modulus (E), Martens hardness (HM), water sorption (wsp), water solubility (wsl) and degree of conversion (DC) of 3D-printed, milled and injection molded splint materials. METHODS Specimens (N = 1140) were fabricated from five 3D-printed (GR-22 flex, GR-10 guide, ProArt Print Splint clear, V-Print Splint, V-Print Splint comfort), five milled (BioniCut, EldyPlus, ProArt CAD Splint clear, Temp Premium Flexible, Thermeo) and two injection molded (PalaXPress clear, Pro Base Cold) materials. FS, E, HM, wsp, wsl and DC were tested initially (24 h, 37 °C, H2O), after water storage (90 d, 37 °C, H2O) as well as after thermal cycling (5000 thermal cycles, 5/55 °C). Data were analyzed with Kolmogorov-Smirnov, Kruskal- Wallis, Mann-Whitney U test and Spearman's correlation (p < 0.05). RESULTS Initially, the mean flexural strength values ranged from 1.9 to 90.7 MPa for printed, 3.8 to 107 MPa for milled and 99.7 to 102 MPa for injection molded materials. The initial mean elastic modulus values were 0.0 to 2.4 GPa for printed, 0.1 to 2.7 GPa for milled and 2.8 GPa for injection molded materials. The initial mean Martens hardness values were 14.5 to 126 N/mm2 for printed, 50.2 to 171 N/mm2 for milled and 143 to 151 N/mm2 for injection molded materials. Initially, the mean water sorption values ranged from 23.1 to 41.2 μg/mm3 for printed, 4.5 to 23.5 μg/mm3 for milled and from 22.5 to 23.3 μg/ mm3 for injection molded materials. The initial mean water solubility values ranged from 2.2 to 7.1 μg/mm3 for printed, 0.0 to 0.5 μg/mm3 for milled and 0.1 to 0.3 μg/mm3 for injection molded materials. After water storage and thermal cycling most of the values decreased and some increased. The mean DC values ranged initially from 72.3 to 94.5 %, after water storage from 74.2 to 96.8 % and after thermal cycling from 75.6 to 95.4 % for the printed materials. SIGNIFICANCE The mechanical and physical properties of printed, milled and injection molded materials for occlusal devices vary and are influenced by aging processes. For clinical applications, materials need to be chosen according to the specific indications.
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Affiliation(s)
- Tina Maleki
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany.
| | - John Meinen
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| | - Andrea Coldea
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| | - Marcel Reymus
- Department of Conservative Dentistry and Peridontology, University Hospital, LMU Munich, Munich, Germany
| | - Daniel Edelhoff
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| | - Bogna Stawarczyk
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
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Mudhaffer S, Althagafi R, Haider J, Satterthwaite J, Silikas N. Effects of printing orientation and artificial ageing on martens hardness and indentation modulus of 3D printed restorative resin materials. Dent Mater 2024; 40:1003-1014. [PMID: 38735775 DOI: 10.1016/j.dental.2024.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/29/2024] [Accepted: 05/03/2024] [Indexed: 05/14/2024]
Abstract
BACKGROUND Three-dimensional (3D) printing is increasingly used to fabricate dental restorations due to its enhanced precision, consistency and time and cost-saving advantages. The properties of 3D-printed resin materials can be influenced by the chosen printing orientation which can impact the mechanical characteristics of the final products. PURPOSE The objective of this study was to evaluate the influence of printing orientation and artificial ageing on the Martens hardness (HM) and indentation modulus (EIT) of 3D-printed definitive and temporary dental restorative resins. METHODS Disk specimens (20 mm diameter × 2 mm height) were additively manufactured in three printing orientations (0°, 45°, 90°) using five 3D-printable resins: VarseoSmile Crownplus (VCP), Crowntec (CT), Nextdent C&B MFH (ND), Dima C&B temp (DT), and GC temp print (GC). The specimens were printed using a DLP 3D-printer (ASIGA MAX UV), while LavaTM Ultimate (LU) and Telio CAD (TC) served as milled control materials. Martens hardness (HM) and indentation modulus (EIT) were tested both before and after storage in distilled water and artificial saliva for 1, 30, and 90 days at 37 °C. RESULTS 90° printed specimens exhibited higher HM than the other orientations at certain time points, but no significant differences were observed in HM and EIT between orientations for all 3D-printed materials after 90 days of ageing in both aging media. LU milled control material exhibited the highest HM and EIT among the tested materials, while TC, the other milled control, showed similar values to the 3D printed resins. CT and VCP (definitive resins) and ND displayed higher Martens parameters compared to DT and GC (temporary resins). The hardness of the 3D-printed materials was significantly impacted by artificial ageing compared to the controls, with ND having the least hardness reduction percentage amongst all 3D-printed materials. The hardness reduction percentage in distilled water and artificial saliva was similar for all materials except for TC, where higher reduction was noted in artificial saliva. SIGNIFICANCE The used 3D printed resins cannot yet be considered viable alternatives to milled materials intended for definitive restorations but are preferable for use as temporary restorations.
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Affiliation(s)
- Shaymaa Mudhaffer
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester, UK; Substitutive Dental Sciences, Faculty of Dentistry, Taibah University, Madinah, Saudi Arabia.
| | - Rana Althagafi
- Substitutive Dental Sciences, Faculty of Dentistry, Taibah University, Madinah, Saudi Arabia
| | - Julfikar Haider
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester, UK; Department of Engineering, Manchester Metropolitan University, Manchester, UK
| | - Julian Satterthwaite
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester, UK
| | - Nick Silikas
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester, UK.
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Orgev A, Donmez MB, Almogbel L, Cakmak G, Marques VR, Kahveci C, Yilmaz B. Cameo and intaglio surface stability and variability of additively, subtractively, and conventionally manufactured occlusal devices after long-term storage. J Prosthet Dent 2024:S0022-3913(24)00427-X. [PMID: 38955603 DOI: 10.1016/j.prosdent.2024.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 06/10/2024] [Accepted: 06/12/2024] [Indexed: 07/04/2024]
Abstract
STATEMENT OF PROBLEM Additive and subtractive manufacturing have become alternative technologies for fabricating occlusal devices. However, knowledge of the long-term stability of occlusal devices fabricated using these recent technologies is limited. PURPOSE The purpose of this in vitro study was to evaluate the cameo and intaglio surface stability and variability of additively, subtractively, and conventionally manufactured occlusal devices after 18 months of storage. MATERIAL AND METHODS A standard tessellation language (STL) file of a dentate maxillary typodont was used to design a master occlusal device. The STL file of this design was used to fabricate occlusal devices additively either with a digital light processing (AM-1) or a continuous liquid interface production (AM-2) printer, subtractively with 2 different 5-axis milling units (SM-1 and SM-2), and conventionally (TM-HP) (n=10). STL files of each device's cameo and intaglio surfaces were generated using a laboratory scanner after fabrication and after 18 months of storage in a moist environment. These generated files were imported into an analysis software program (Geomagic Control X) to analyze the dimensional stability of tested devices by using the root mean square method. The average deviation values defined the variability of measured changes over time. Cameo and intaglio surface deviations were analyzed using the Kruskal-Wallis and Dunn tests, while the variability of measured deviations was analyzed with 1-way analysis of variance and the Tukey HSD tests (α=.05). RESULTS Significant differences were observed among tested devices when the intaglio surface deviations and the cameo surface variability were considered (P<.001). SM-2 had significantly higher intaglio surface deviations than AM-1, SM-1, and AM-2 (P≤.036). Among the test groups, AM-1 had the greatest cameo surface variability (P≤.004). CONCLUSIONS SM-2 resulted in lower intaglio surface stability than the additive and the other subtractive manufacturing technologies, while AM-1 led to the highest cameo surface variability among the test groups.
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Affiliation(s)
- Ahmet Orgev
- Clinical Associate Professor, Department of Restorative Dentistry, School of Dental Medicine, University at Buffalo, Buffalo, NY.
| | - Mustafa Borga Donmez
- Associate Professor, Department of Prosthodontics, Faculty of Dentistry, Istinye University, Istanbul, Turkey; and ITI Scholar, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Lolowh Almogbel
- Fellow, Advanced Education Program in Implant Dentistry, Loma Linda University School of Dentistry, Loma Linda, Calif.; Restorative and Prosthetic Dental Sciences Department, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; King Abdullah International Medical Research Centre, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Gulce Cakmak
- Senior Research Associate, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Vinicius Rizzo Marques
- Digital Implant Fellow, Department of Restorative Dentistry, School of Dental Medicine, University at Buffalo, Buffalo, NY
| | - Cigdem Kahveci
- Assistant Professor, Department of Prosthodontics, Giresun University Faculty of Dentistry, Giresun, Turkey
| | - Burak Yilmaz
- Associate Professor, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland; Associate Professor, Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland; and Adjunct Professor, Division of Restorative and Prosthetic Dentistry, The Ohio State University, Columbus, Ohio
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Valenti C, Federici MI, Coniglio M, Betti P, Pancrazi GP, Tulli O, Masciotti F, Nanussi A, Pagano S. Mechanical and biological properties of polymer materials for oral appliances produced with additive 3D printing and subtractive CAD-CAM techniques compared to conventional methods: a systematic review and meta-analysis. Clin Oral Investig 2024; 28:396. [PMID: 38916682 DOI: 10.1007/s00784-024-05772-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Accepted: 06/11/2024] [Indexed: 06/26/2024]
Abstract
OBJECTIVES The aim of this review was to analyze mechanical and biological properties of resin materials used with subtractive or additive techniques for oral appliances fabrication and compare them to those conventionally manufactured. MATERIALS AND METHODS The protocol was registered online at Open Science Framework (OSF) registries ( https://osf.io/h5es3 ) and the study was based on the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P). An electronic search was conducted on MEDLINE (via PubMed), Scopus, and Web of Science from 1 February 2022 to 1 May 2022. INCLUSION CRITERIA in vitro and in vivo studies published in the last 10 years, with CAD-CAM or 3D printed resins for occlusal splints. Data considered homogenous were subjected to meta-analysis (95% confidence interval [CI]; α = 0.05) with Stata17 statistical software. Since all variables were continuous, the Hedge g measure was calculated. A fixed-effects model was used for I2 = 0%, while statistical analysis was conducted using a random-effects model with I2 > 0%. RESULTS 13 studies were included after full-text reading. The mechanical properties most studied were wear, flexural strength, surface hardness and surface roughness, while only 1 study investigated biological properties, performing the XTT viability assay. For the meta-analysis, only surface roughness, volume loss, and flexural strength were selected. Considering surface roughness, the subtractive specimen had a lower average value compared to traditional ones (Hedge's g with 95% CI = -1.25[ -1.84, - 0.66]). No significant difference was detected in terms of volume loss (P > 0.05) between the groups (Hedge's g with 95% CI = -0.01 [-2.71, - 2.68]). While flexural strength was higher in the control group (Hedge's g with 95% CI = 2.32 [0.10-4.53]). CONCLUSION 3D printed materials showed properties comparable to conventional resins, while milled splint materials have not shown better mechanical performance compared with conventional heat-cured acrylic resin. Polyetheretherketone (PEEK) have great potential and needs to be further investigated. Biological tests on oral cell populations are needed to confirm the long-term biocompatibility of these materials. CLINICAL RELEVANCE The use of "mixed splints" combining different materials needs to be improved and evaluated in future research to take full advantage of different characteristics and properties.
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Affiliation(s)
- Chiara Valenti
- CISAS "Giuseppe Colombo", University of Padua, Via Venezia, 15, Padua, 35131, Italy
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
| | - Maria Isabella Federici
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
| | - Maddalena Coniglio
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy.
- Strada vicinale Via delle Corse, S. Andrea delle Fratte, Perugia, 06132, Italy.
| | - Paolo Betti
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
| | - Gian Piero Pancrazi
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
| | - Ornella Tulli
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
| | - Francesca Masciotti
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
| | | | - Stefano Pagano
- Department of Medicine and Surgery, Faculty of Dentistry, University of Perugia, S. Andrea delle Fratte, Perugia, 06156, Italy
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Revilla-León M, Cascos-Sánchez R, Zeitler JM, Barmak AB, Kois JC, Gómez-Polo M. Influence of print orientation and wet-dry storage time on the intaglio accuracy of additively manufactured occlusal devices. J Prosthet Dent 2024; 131:1226-1234. [PMID: 36635137 DOI: 10.1016/j.prosdent.2022.12.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 12/06/2022] [Accepted: 12/06/2022] [Indexed: 01/11/2023]
Abstract
STATEMENT OF PROBLEM Different factors can affect the manufacturing accuracy of additively manufactured dental devices; however, the influence of print orientation and wet-dry storage time on their intaglio accuracy remains uncertain. PURPOSE The purpose of this in vitro study was to assess the effect of print orientation (0, 45, 70, and 90 degrees) and wet-dry storage time (0, 30, 60, and 90 days) on the intaglio accuracy of additively manufactured occlusal devices. MATERIAL AND METHODS An occlusal device design was obtained in a standard tessellation language (STL) file format (control file) which was used to fabricate all the specimens by using a stereolithography printer (Form 3+) and a biocompatible resin material (Dental LT Clear Resin, V2). Four groups were created based on the print orientation used to manufacture the specimens: 0, 45, 70, and 90 degrees. Each group was divided into 4 subgroups depending on the time elapsed between manufacturing and accuracy evaluation: 0, 30, 60, and 90 days. For the subgroup 0, a desktop scanner (T710) was used to digitize all the specimens. The 30-day subgroup specimens were stored for 30 days with the following daily storage protocol: 16 hours inside a dry lightproof container, followed by 8 hours in artificial saliva (1700-0305 Artificial Saliva) inside the same lightproof container. The specimens were then digitized by following the same procedures used for subgroup 0. For the subgroups 60 and 90, the identical procedures described for subgroup 30 were completed but after 60 and 90 days of storage, respectively. The reference STL file was used to measure the intaglio discrepancy with the experimental scans obtained among the different subgroups by using the root mean square error calculation. Two-way ANOVA and post hoc Tukey pairwise comparison tests were used to analyze the data (α=.05). RESULTS Print orientation (P<.001) and usage time (P<.001) were significant predictors of the trueness value obtained. Additionally, the 0-degree print orientation at day 0 group demonstrated the best trueness value among all the groups tested (P<.05). No significant trueness discrepancies were found among the 45-, 70-, and 90-degree print orientation, or among the 30, 60, and 90 days of storage. A significant precision difference was found in the variance between print orientation groups across usage time subgroups. CONCLUSIONS The print orientation and wet-dry storage times tested influenced the trueness and precision of the intaglio surfaces of the occlusal devices manufactured with the 3D printer and material selected.
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Affiliation(s)
- Marta Revilla-León
- Affiliate Professor, Graduate Prosthodontics, Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, Wash; Faculty and Director of Research and Digital Dentistry, Kois Center, Seattle, Wash; Affiliate Professor, Graduate Prosthodontics, Department of Prosthodontics, School of Dental Medicine, Tufts University, Boston, Mass
| | - Rocío Cascos-Sánchez
- Postgraduate Advanced in Implant-Prosthodontics, Department of Conservative Dentistry and Prosthodontics, School of Dentistry, Complutense University of Madrid, Madrid, Spain
| | | | - Abdul B Barmak
- Assistant Professor Clinical Research and Biostatistics, Eastman Institute of Oral Health, University of Rochester Medical Center, Rochester, NY
| | - John C Kois
- Founder and Director, Kois Center, Seattle, Wash; Affiliate Professor, Graduate Prosthodontics, Department of Restorative Dentistry, University of Washington, Seattle, Wash; Private Practice, Seattle, Wash
| | - Miguel Gómez-Polo
- Associate Professor, Department of Conservative Dentistry and Prosthodontics, Director of postgraduate program of Advanced in Implant-Prosthodontics, School of Dentistry, Complutense University of Madrid, Madrid, Spain.
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Ateş G, Demirel M, Donmez MB, Dayan SÇ, Sülün T. Effect of material and antagonist type on the wear of occlusal devices with different compositions fabricated by using conventional, additive, and subtractive manufacturing. J Prosthet Dent 2024; 131:1235.e1-1235.e8. [PMID: 38594086 DOI: 10.1016/j.prosdent.2024.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/11/2024]
Abstract
STATEMENT OF PROBLEM Additive (AM) and subtractive (SM) manufacturing have become popular for fabricating occlusal devices with materials of different chemical compositions. However, knowledge on the effect of material and antagonist type on the wear characteristics of occlusal devices fabricated by using different methods is limited. PURPOSE The purpose of this in vitro study was to evaluate the effect of material and antagonist type on the wear of occlusal devices fabricated by using conventional manufacturing, AM, and SM. MATERIAL AND METHODS Two-hundred and forty Ø10×2-mm disk-shaped specimens were fabricated by using heat-polymerized polymethylmethacrylate (control, CM), AM clear device resin fabricated in 3 different orientations (horizontal [AMH], diagonal [AMD], and vertical [AMV]), SM polymethylmethacrylate (SMP), and SM ceramic-reinforced polyetheretherketone (SMB) (n=40). Specimens were then divided into 4 groups based on the antagonists: steatite ceramic (SC); multilayered zirconia (ZR); lithium disilicate (EX); and zirconia-reinforced lithium silicate (ZLS) used for thermomechanical aging (n=10). After aging, the volume loss (mm3) and maximum wear depth (μm) were digitally evaluated. Data were analyzed with 2-way analysis of variance and Tukey honestly significant difference tests (α=.05). RESULTS The interaction between the device material and the antagonist affected volume loss and maximum depth of wear (P<.001). AMH had volume loss and depth of wear that was either similar to or higher than those of other materials (P≤.044). When SC was used, CM had higher volume loss and depth of wear than AMV, and, when EX was used, AMD had higher volume loss and depth of wear than SMP (P≤.013). SC and ZR led to higher volume loss of CM and AMH than EX and led to the highest depth of wear for these materials, while ZR also led to the highest volume loss and depth of wear of AMD and AMV (P≤.019). EX led to the lowest volume loss and depth of wear of AMV and SMP and to the lowest depth of wear of AMH (P≤.021). Regardless of the antagonist, SMB had the lowest volume loss and depth of wear (P≤.005). CONCLUSIONS AMH mostly had higher volume loss and depth of wear, while SMB had the lowest volume loss, and its depth of wear was not affected by the tested antagonists. ZR mostly led to higher volume loss and maximum depth of wear, while EX mostly led to lower volume loss and maximum depth of wear of the tested occlusal device materials.
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Affiliation(s)
- Gökçen Ateş
- Postdoctoral Research Associate, Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey; and ITI Scholar, Department of Prosthodontics, University of São Paulo (USP), São Paulo, Brazil
| | - Münir Demirel
- Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Biruni University, Istanbul, Turkey
| | - Mustafa Borga Donmez
- Associate Professor, Department of Prosthodontics, Faculty of Dentistry, Istinye Univeristy, İstanbul, Turkey; and ITI Scholar, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
| | - Süleyman Çağatay Dayan
- Associate Professor, Program of Dental Technicians, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Tonguç Sülün
- Professor, Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey
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Simeon P, Unkovskiy A, Saadat Sarmadi B, Nicic R, Koch PJ, Beuer F, Schmidt F. Wear resistance and flexural properties of low force SLA- and DLP-printed splint materials in different printing orientations: An in vitro study. J Mech Behav Biomed Mater 2024; 152:106458. [PMID: 38364445 DOI: 10.1016/j.jmbbm.2024.106458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/29/2024] [Accepted: 02/05/2024] [Indexed: 02/18/2024]
Abstract
OBJECTIVES To investigate the influence of material and printing orientation on wear resistance and flexural properties of one low force SLA- and two DLP-printed splint materials and to compare these 3D-printed splints to a subtractively manufactured splint material. METHODS Two DLP-printed (V-Print splint, LuxaPrint Ortho Plus) and one low force SLA-printed (Dental LT Clear) material, where specimens were printed in three printing orientations (0°, 45°, 90°), were investigated. In addition, one milled splint material (Zirlux Splint Transparent) was examined. A total of 160 specimens were produced for both test series. The two-body wear test was performed in a chewing simulator (80'000 cycles at 50 N with 5-55 °C thermocycling). Steatite balls were used as antagonists. The wear pattern was analyzed with a 3D digital microscope in terms of maximum vertical intrusion depth (mm) and total volume loss (mm³). The flexural properties were investigated by three-point bending in accordance with ISO 20795-1: 2013 (denture base polymers). The flexural strength (MPa) and the flexural modulus (MPa) were measured. Two-way ANOVA was performed to investigate the effects of the two independent variables material and printing orientation for the three 3D-printed materials. The comparison of the printing orientations within one material was carried out with one-way ANOVA with post-hoc Tukey tests. RESULTS Two-way ANOVA revealed that wear and flexural properties are highly dependent on the 3D-printed material (p < 0.001). Across groups, a significant effect was observed for wear depth (p = 0.031) and wear volume (p = 0.044) with regard to printing orientation but this was not found for flexural strength (p = 0.080) and flexural modulus (p = 0.136). One-way ANOVA showed that both DLP-printed groups showed no significant differences within the printing orientations in terms of wear and flexural properties. Dental LT Clear showed that 90° oriented specimens had higher flexural strength than 0° oriented ones (p < 0.001) and 45° oriented specimens also showed higher values than 0° ones (p = 0.038). No significant differences were observed within the printing orientations for flexural modulus and wear behaviour within this group. T-tests showed that the milled splints exhibited statistically higher wear resistance and flexural properties compared to all three 3D-printed splint materials (p < 0.001) and that highly significant differences were found between the 3D-printed splint materials for both test series. CONCLUSION Within the limitations of this in vitro study, it can be stated that wear behaviour and flexural properties are highly dependent on the 3D-printed material itself. Currently, milled splints exhibit higher wear resistance and flexural properties compared to 3D-printed splint materials. The printing orientation has a minor influence on the properties investigated. Nevertheless, two-way ANOVA also showed a significant influence of printing orientation in the wear test across groups and one-way ANOVA detected significant effects for SLA material in terms of flexural strength, with printing in 90° showing the highest flexural strength. Therefore, anisotropy was found in SLA material, but it can be limited with the employed printing parameters. Both DLP-printed materials showed no significant difference within the printing orientation.
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Affiliation(s)
- Philipp Simeon
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Alexey Unkovskiy
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Aßmannshauser Str. 4-6, 14197, Berlin, Germany; Department of Dental Surgery, Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Street, 19с1, Moscow, 119146, Russia
| | - Bardia Saadat Sarmadi
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Robert Nicic
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Petra Julia Koch
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Orthodontics and Orthofacial Orthopedics, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Florian Beuer
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Franziska Schmidt
- Charité - Universitätsmedizin Berlin, Center for Oral Health Sciences CC3, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Aßmannshauser Str. 4-6, 14197, Berlin, Germany.
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Siqueira JRCDS, Rodriguez RMM, Campos TMB, Ramos NDC, Bottino MA, Tribst JPM. Characterization of Microstructure, Optical Properties, and Mechanical Behavior of a Temporary 3D Printing Resin: Impact of Post-Curing Time. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1496. [PMID: 38612010 PMCID: PMC11012777 DOI: 10.3390/ma17071496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/17/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024]
Abstract
The present study aimed to characterize the microstructure of a temporary 3D printing polymer-based composite material (Resilab Temp), evaluating its optical properties and mechanical behavior according to different post-curing times. For the analysis of the surface microstructure and establishment of the best printing pattern, samples in bar format following ISO 4049 (25 × 10 × 3 mm) were designed in CAD software (Rhinoceros 6.0), printed on a W3D printer (Wilcos), and light-cured in Anycubic Photon for different lengths of time (no post-curing, 16 min, 32 min, and 60 min). For the structural characterization, analyses were carried out using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The mechanical behavior of this polymer-based composite material was determined based on flexural strength tests and Knoop microhardness. Color and translucency analysis were performed using a spectrophotometer (VITA Easy Shade Advanced 4.0), which was then evaluated in CIELab, using gray, black, and white backgrounds. All analyses were performed immediately after making the samples and repeated after thermal aging over two thousand cycles (5-55 °C). The results obtained were statistically analyzed with a significance level of 5%. FT-IR analysis showed about a 46% degree of conversion on the surface and 37% in the center of the resin sample. The flexural strength was higher for the groups polymerized for 32 min and 1 h, while the Knoop microhardness did not show a statistical difference between the groups. Color and translucency analysis also did not show statistical differences between groups. According to all of the analyses carried out in this study, for the evaluated material, a post-polymerization time of 1 h should be suggested to improve the mechanical performance of 3D-printed devices.
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Affiliation(s)
- Joyce Roma Correia dos Santos Siqueira
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, São José dos Campos 12245-000, Brazil; (J.R.C.d.S.S.); (R.M.M.R.); (N.d.C.R.); (M.A.B.)
| | - Rita Maria Morejon Rodriguez
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, São José dos Campos 12245-000, Brazil; (J.R.C.d.S.S.); (R.M.M.R.); (N.d.C.R.); (M.A.B.)
| | - Tiago Moreira Bastos Campos
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, Brazil;
| | - Nathalia de Carvalho Ramos
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, São José dos Campos 12245-000, Brazil; (J.R.C.d.S.S.); (R.M.M.R.); (N.d.C.R.); (M.A.B.)
| | - Marco Antonio Bottino
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, São José dos Campos 12245-000, Brazil; (J.R.C.d.S.S.); (R.M.M.R.); (N.d.C.R.); (M.A.B.)
| | - João Paulo Mendes Tribst
- Department of Reconstructive Oral Care, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit Amsterdam, 1081 LA Amsterdam, The Netherlands
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Benli M, Al-Haj Husain N, Ozcan M. Mechanical and chemical characterization of contemporary occlusal splint materials fabricated with different methods: a systematic review. Clin Oral Investig 2023; 27:7115-7141. [PMID: 37910242 DOI: 10.1007/s00784-023-05360-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 10/22/2023] [Indexed: 11/03/2023]
Abstract
OBJECTIVE To systematically review studies on various occlusal splint materials and describe their mechanical and chemical properties. METHODS MEDLINE (PubMed), Scopus, and Web of Science searches were conducted for in vitro studies focusing on occlusal splint materials. Two reviewers performed an assessment of the identified studies and data abstraction independently, and this was complimented by an additional hand search. The articles were limited to those in the English language that were published between January 1st, 2012, and December 1st, 2022. RESULTS The initial search yielded 405 search results of which 274 were selected for full-text review following abstract evaluation. 250 articles that did not meet the inclusion criteria were excluded, and the remaining 25 articles (with 1 article identified from the reference lists of included articles) providing mechanical and chemical values were used in this review. Poly methyl methacrylate (PMMA) -based occlusal splint materials showed the highest values in terms of hardness, wear resistance, flexural strength, flexural modulus, e-modulus, and fracture toughness. The material group with the highest water sorption and water solubility was 3D printed (PR) splint materials. In addition, the lowest degree of double bond conversion was also observed in this group of materials. CONCLUSIONS The outcome of this review suggests that mechanically and chemically acceptable properties can be attained with PMMA-based occlusal splint materials using both conventional and digital production methods. PR splint materials should not be considered as the primary choice for long-term treatments due to their low mechanical and chemical properties. CLINICAL RELEVANCE This review provides clinical recommendations for selecting the appropriate material and fabrication method for occlusal splints while taking the patients' needs and the materials´ mechanical and chemical properties into account.
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Affiliation(s)
- Merve Benli
- James B. Edwards College of Dental Medicine, Department of Oral Rehabilitation, Division of Removable Prosthodontics, MUSC, Charleston, USA.
- Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey.
| | - Nadin Al-Haj Husain
- Division of Dental Biomaterials, Clinic for Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, 8032, Zurich, Switzerland
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, 3010, Bern, Switzerland
- Clinic of Masticatory Disorders, Center of Dental Medicine, University of Zurich, 8032, Zurich, Switzerland
| | - Mutlu Ozcan
- Division of Dental Biomaterials, Center for Dental Medicine, Clinic for Reconstructive Dentistry, University of Zurich, Plattenstrasse 11, 8032, Zurich, Switzerland
- Clinic for Chewing Function Disturbances, Center for Dental Medicine, Clinic for Reconstructive Dentistry, University of Zurich, Plattenstrasse 11, 8032, Zurich, Switzerland
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Rosello Jimenez JR, Fuchs F, Schmohl L, Schulz-Siegmund M, Koenig A. Aging Processes and Their Influence on the Mechanical Properties of Printable Occlusal Splint Materials. Polymers (Basel) 2023; 15:4574. [PMID: 38232021 PMCID: PMC10707959 DOI: 10.3390/polym15234574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 11/17/2023] [Accepted: 11/21/2023] [Indexed: 01/19/2024] Open
Abstract
Three-dimensional (3D)-printed occlusal splints are becoming more prevalent in the treatment of tooth substance loss due to their fast and cost-effective production. The purpose of this in vitro study was to investigate whether the mechanical properties (tensile strength-TS, modulus of elasticity in tension-ME, and Vickers hardness-HV) vary between the materials (printed dimethacrylate-based resins: Keyprint KeySplint soft-KEY, Luxaprint Ortho Plus-LUX, V-Print splint-VPR, printed methacrylate-based resins Freeprint splint 2.0-FRE, and milled methacrylate-based material, CLEAR splint-CLE), and the influence of aging processes (extraoral storage conditions and nightly or daily use) was examined. The printed methacrylate-based resins (FRE, LUX, and VPR) had much higher TS (43.7-48.5 MPa compared to 12.3-13.3 MPa), higher ME (2.01-2.37 GPa compared to 0.43-0.72 GPa), and higher HV (11.8-15.0 HV compared to 3.3-3.5 HV) than both of the methacrylate-based resins (KEY and CLE) after the production process. Although the TS, ME, and HV of the printed dimethacrylate resins (FRE, LUX, and VPR) decreased significantly under humid conditions with possibly elevated temperatures (thermocycling as well as 37 °C), these mechanical properties were significantly higher than both methacrylate-based resins (KEY and CLE). Therefore, printed dimethacrylate resins should be used rather than methacrylate-based resins for high expected masticatory forces, low wall thicknesses, or very long wearing times (≥6 months).
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Affiliation(s)
- Jan Raffael Rosello Jimenez
- Department of Prosthodontics and Material Sciences, Leipzig University, 04103 Leipzig, Germany
- Private Practice, Zahnarztpraxis Jan Rosello, 04654 Frohburg, Germany
| | - Florian Fuchs
- Department of Prosthodontics and Material Sciences, Leipzig University, 04103 Leipzig, Germany
| | - Leonie Schmohl
- Department of Prosthodontics and Material Sciences, Leipzig University, 04103 Leipzig, Germany
| | | | - Andreas Koenig
- Department of Prosthodontics and Material Sciences, Leipzig University, 04103 Leipzig, Germany
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11
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Orgev A, Levon JA, Chu TMG, Morton D, Lin WS. The effects of manufacturing technologies on the surface accuracy of CAD-CAM occlusal splints. J Prosthodont 2023; 32:697-705. [PMID: 36227731 DOI: 10.1111/jopr.13610] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 10/01/2022] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To investigate the effects of the manufacturing technologies on the surface (cameo and intaglio) accuracy (trueness and precision) of computer-aided design and computer-aided manufacturing (CAD-CAM) occlusal splints. MATERIALS AND METHODS The digital design of the master occlusal splint was designed in a CAD software program. Six groups (n = 10) were tested in this study, including Group 1 - Milling (Wax), Group 2 - Heat-polymerizing, Group 3 - Milling (M series), Group 4 - Milling (DWX-51/52D), Group 5 - 3D-printing (Cares P30), and Group 6 - 3D-printing (M2). The study samples were placed in a scanning jig fabricated from putty silicone and Type III dental stone. The study samples were then scanned with a laboratory scanner at the intaglio and cameo surfaces, and the scanned files were exported in standard tessellation language (STL) file format. The master occlusal splint STL file, was used as a reference to compare with all scanned samples at the intaglio and cameo surfaces in a surface matching software program. Root mean square (RMS, measured in mm, absolute value) values were calculated by the software for accuracy comparisons. Group means were used as the representation of trueness, and the standard deviation for each group was calculated as a measure of precision. Color maps were recorded to visualize the areas of deviation between study samples and the master occlusal splint file. The data were normalized and transformed to rank scores, and one-way ANOVA was used to test for the differences between the groups. Pairwise comparisons were made between different groups. Fishers least square differences were used to account for the family-wise error rate. A 5% significance level was used for all the tests. RESULTS The null hypotheses were rejected. The manufacturing technologies significantly affected the trueness of occlusal splints at both intaglio and cameo surfaces (p < 0.001). At the cameo surfaces, Group 1 - Milling (Wax) (0.03 ± 0.02 mm), Group 3 - Milling (M series) (0.04 ± 0.01 mm), and Group 4 - Milling (DWX-51/52D) (0.04 ± 0.01 mm) had the smallest mean RMS values and highest trueness. Group 3 had the smallest standard deviation and highest precision among all groups (p < 0.001, except p = 0.005 when compared with Group 2). Group 5 had the largest standard deviation and lowest precision among all groups (p < 0.001). At the intaglio surfaces, Group 1 - Milling (Wax) (0.06 ± 0.01 mm) had the smallest RMS values and highest trueness among all groups (p < 0.001), and Group 2 - Heat-polymerizing (0.20 ± 0.03 mm) and Group 5 - 3D-printing (Cares P30) (0.15 ± 0.05 mm) had significantly larger mean RMS and standard deviation values than all other groups (p < 0.001), with lowest trueness and precision. In the color maps, Group 2 - Heat-polymerizing and Group 5 - 3D-printing (Cares P30) showed the most discrepancies with yellow and red (positive discrepancies) in most areas, and Group 1 - Milling (Wax) showed the best and most uniform surface matching with the most area in green. CONCLUSION The manufacturing technologies significantly affected the trueness and precision of occlusal splints at both intaglio and cameo surfaces. The 5-axis milling units and industrial-level CLIP 3D-printer could be considered to achieve surface accuracy of occlusal splints.
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Affiliation(s)
- Ahmet Orgev
- Department of Restorative Dentistry, University at Buffalo School of Dental Medicine, Buffalo, New York
| | - John A Levon
- Department of Prosthodontics, Indiana University School of Dentistry, Indianapolis, Indiana
| | - Tien-Min G Chu
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, Indiana
| | - Dean Morton
- Department of Prosthodontics, Indiana University School of Dentistry, Indianapolis, Indiana
| | - Wei-Shao Lin
- Department of Prosthodontics, Indiana University School of Dentistry, Indianapolis, Indiana
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Abad-Coronel C, Ruano Espinosa C, Ordóñez Palacios S, Paltán CA, Fajardo JI. Comparative Analysis between Conventional Acrylic, CAD/CAM Milled, and 3D CAD/CAM Printed Occlusal Splints. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6269. [PMID: 37763547 PMCID: PMC10532716 DOI: 10.3390/ma16186269] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/15/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023]
Abstract
The development of digital technologies has allowed for the fabrication of new materials; however, it makes it difficult to choose the best methods to obtain occlusal splints with optimal properties, so it is essential to evaluate the effectiveness of these materials. The aim of the study is to compare the fracture resistance of occlusal splints made of different materials after thermo-mechanical aging. METHODS A total of 32 samples were made from 4 materials (two 3D printed polymeric materials, a PMMA disc for CAD/CAM, and a conventional heat-cured acrylic resin); subsequently, the fracture test was performed using the load compression mode applied occlusally on the splint surface. STATISTICAL ANALYSIS Four statistical tests were used (Shapiro-Wilk, Levene's test, ANOVA, and Tukey's HSD test). RESULTS The following study showed that there are differences in fracture strength among the four materials investigated, where the highest strength was observed in the milled splint, with a mean of 3051.2 N (newton) compared to the strength of the flexible splint with 1943.4 N, the printed splint with 1489.9 N, and the conventional acrylic splint with 1303.9 N. CONCLUSIONS The milled splints were the most resistant to fracture. Of the printed splints, the splint made with flexural rigid resin withstood the applied forces in acceptable ranges, so its clinical indication may be viable. Although the results of this research indicated differences in the mechanical properties between the CAD/CAM and conventional fabrication methods, the selection may also be influenced by processing time and cost, since with a CAD/CAM system there is a significant reduction in the production time of the splint material.
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Affiliation(s)
- Cristian Abad-Coronel
- CAD/CAM Materials and Digital Dentistry Research Group, Faculty of Dentistry, Universidad de Cuenca, Cuenca 010204, Ecuador
| | | | | | - César A. Paltán
- New Materials and Transformation Processes Research Group GiMaT, Universidad Politécnica Salesiana, Cuenca 010105, Ecuador; (C.A.P.); (J.I.F.)
| | - Jorge I. Fajardo
- New Materials and Transformation Processes Research Group GiMaT, Universidad Politécnica Salesiana, Cuenca 010105, Ecuador; (C.A.P.); (J.I.F.)
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Prpic V, Spehar F, Stajdohar D, Bjelica R, Cimic S, Par M. Mechanical Properties of 3D-Printed Occlusal Splint Materials. Dent J (Basel) 2023; 11:199. [PMID: 37623295 PMCID: PMC10453325 DOI: 10.3390/dj11080199] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/30/2023] [Accepted: 08/14/2023] [Indexed: 08/26/2023] Open
Abstract
Data regarding the mechanical properties of three-dimensionally (3D) printed materials for occlusal splint manufacturing are scarce. The aim of the present study was to evaluate the flexural strength and surface hardness of modern 3D-printed occlusal splint materials and compare them with two control groups, namely, milled and conventional cold-polymerized occlusal splint materials. A total of 140 rectangular specimens were manufactured for the present study. The specimens were prepared in accordance with the International Organization for Standardization standards (ISO 20795-1:2013). Five 3D-printed (NextDent Ortho Rigid, Dental LT Clear, Dentona Flexisplint, Cosmos Bite Splint, and ProArt Print Splint), one milled (ProArt CAD Splint), and one cold-polymerized (ProBase Cold) occlusal splint materials were used to determine flexural strength and surface hardness values. The three-point flexure test was used for the determination of flexural strength values, while Vickers hardness was measured to determine surface hardness. Ten specimens (n = 10) of each material were tested using these procedures. One-way ANOVA and Tukey's post-hoc test were used to analyze the obtained results (α = 0.05). The values of flexural strength ranged from 46.1 ± 8.2 MPa to 106 ± 8.3 MPa. The Vickers hardness values ranged from 4.9 ± 0.5 VHN to 20.6 ± 1.3 VHN. Significant differences were found among the tested materials (p < 0.0001). The milled and cold-polymerized materials yielded higher values for both flexural strength (only one 3D-printed resin had comparable results to cold-polymerized acrylics) and surface hardness. There are differences in the mechanical properties of the various tested occlusal splint materials. The flexural strength of most of the 3D-printed materials and their surface hardness values are still inferior when compared to the milled or cold-polymerized materials.
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Affiliation(s)
- Vladimir Prpic
- Department of Fixed Prosthodontics, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia;
| | - Filipa Spehar
- School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (F.S.); (D.S.)
| | - Dominik Stajdohar
- School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (F.S.); (D.S.)
| | - Roko Bjelica
- Department of Oral Surgery, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia;
| | - Samir Cimic
- Department of Removable Prosthodontics, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia;
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Da Silva TM, Immich F, De Araujo TS, Lund RG, Da Silva AF, Piva E, Da Rosa WLDO. Photosensitive resins used in additive manufacturing for oral application in dentistry: A scoping review from lab to clinic. J Mech Behav Biomed Mater 2023; 141:105732. [PMID: 36898354 DOI: 10.1016/j.jmbbm.2023.105732] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 01/21/2023] [Accepted: 02/11/2023] [Indexed: 03/05/2023]
Affiliation(s)
| | - Felipe Immich
- School of Dentistry, Federal University of Pelotas, RS, Brazil.
| | | | - Rafael Guerra Lund
- Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
| | - Adriana Fernandes Da Silva
- Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
| | - Evandro Piva
- Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
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15
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de Paula Lopez V, Dias Corpa Tardelli J, Botelho AL, Marcondes Agnelli JA, Cândido Dos Reis A. Mechanical performance of 3-dimensionally printed resins compared with conventional and milled resins for the manufacture of occlusal devices: A systematic review. J Prosthet Dent 2023:S0022-3913(22)00766-1. [PMID: 36631367 DOI: 10.1016/j.prosdent.2022.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 12/11/2022] [Accepted: 12/13/2022] [Indexed: 01/11/2023]
Abstract
STATEMENT OF PROBLEM Digital methods for manufacturing occlusal devices provide advantages over conventional techniques, but information about the mechanical properties of 3-dimensionally (3D) printed resins is scarce. PURPOSE The purpose of this systematic review was to evaluate the literature to determine whether 3D-printed resins for occlusal devices present satisfactory mechanical performance when compared with milled and conventional heat polymerized and autopolymerized resins. MATERIAL AND METHODS This systematic review followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and was registered in the Open Science Framework. The search strategy was applied without restriction of time and language to Embase, PubMed, Scopus, Science Direct, and Web of Science databases, and to the nonpeer-reviewed literature in ProQuest and Google Scholar. The selection process was conducted independently in 2 stages by 2 reviewers according to the eligibility criteria. The risk of bias was analyzed by using a checklist of important parameters to be considered. The systematic review considered the population, intervention, comparison, outcome, studies (PICOS) format, where population was resins for 3D printing of occlusal devices, intervention was inherent characteristics of the resin, comparison was conventional heat polymerized, autopolymerized, and milled resins, outcome was mechanical performance, and studies were in vitro experimental studies. RESULTS A total of 1430 articles were found with the search strategy. After removing 182 duplicates found in Rayyan, the title and abstract of 1248 articles were evaluated, of which 37 articles were screened from the databases, 23 were selected for full reading, and 6 met the eligibility criteria and were included in this review; 1 had a low risk of bias and 5 had a moderate risk. An additional search of the reference list of included articles did not result in the inclusion of any articles. A quantitative meta-analysis could not be performed because of the heterogeneity of the included studies regarding the type of resin used and the method for evaluating mechanical performance. CONCLUSIONS Resins for 3D printing had satisfactory mechanical performance for interocclusal devices when compared with conventional heat polymerized and autopolymerized resins, except for hardness. Milled resins were better than 3D-printed resins in hardness, wear resistance, flexural strength, flexural modulus, and fracture resistance when printing angle and thickness were not considered. Further development is needed in terms of printing techniques and chemical composition, as they are important for optimal mechanical properties and clinical performance.
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Affiliation(s)
- Vitor de Paula Lopez
- Undergraduate Student, Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Juliana Dias Corpa Tardelli
- Postgraduate Student, Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - André Luis Botelho
- Postdoctoral Student, Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - José Augusto Marcondes Agnelli
- Senior Professor, Department of Materials Engineering, Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), São Carlos, Brazil
| | - Andréa Cândido Dos Reis
- Associate Professor, Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil.
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Guimaraes DM, Campaner M, Santos RWD, Pesqueira AA, Medeiros RAD. Evaluation of the mechanical properties of different materials for manufacturing occlusal splints. Braz Oral Res 2023; 37:e034. [PMID: 37132723 DOI: 10.1590/1807-3107bor-2023.vol37.0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 11/21/2021] [Indexed: 05/04/2023] Open
Abstract
This study aimed to compare the mechanical properties of various occlusal plate materials by analyzing surface roughness, Knoop microhardness, flexural strength, and modulus of elasticity. Fifty samples were prepared and classified as SC (self-curing acrylic resin), WB (heat-cured acrylic resin), ME (acrylic resin polymerized by microwave energy), P (resin print), and M (polymethylmethacrylate polymer block for computer-aided design/computer-aided manufacturing). The data were analyzed using a one-way analysis of variance and Tukey's honestly significant difference test. Surface roughness was the same in all groups. The surface hardness of group M was statistically superior. The samples from groups P and M had higher flexural strength than other samples. The modulus of elasticity of group SC was statistically lower than that of other groups. The mechanical properties of the materials used to make the occlusal plates differed, and group M achieved the best results in all analyses. Therefore, clinicians must consider the material used to manufacture long-lasting and efficient occlusal splints.
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Affiliation(s)
| | - Marcio Campaner
- Universidade Estadual Paulista - Unesp, Aracatuba Dental School, Department of Dental Materials and Prosthodontics, Aracatuba, SP, Brazil
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Altarazi A, Haider J, Alhotan A, Silikas N, Devlin H. Assessing the physical and mechanical properties of 3D printed acrylic material for denture base application. Dent Mater 2022; 38:1841-1854. [PMID: 36195470 DOI: 10.1016/j.dental.2022.09.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/15/2022] [Accepted: 09/22/2022] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Three-dimensional (3D) printing is increasingly being utilised in the dental field because of its time-saving potential and cost effectiveness. It enables dental practitioners to eliminate several fabrication steps, achieve higher precision, and attain consistency in complex prosthetic models. The properties of 3D-printed resin materials can be affected by many factors, including the printing orientation (PO) and insufficient post-curing time (CT). This study aimed to investigate the effect of PO and CT on the mechanical and physical properties of a 3D-printed denture base resin (NextDent). METHODS 3D-printed specimens were fabricated in 0°, 45°, and 90° POs, followed by three CTs (20, 30, and 50 min). The microhardness was tested using a Vickers hardness test, while the flexural property was evaluated using a three-point bending test. Sorption and solubility were measured after the specimens had been stored in an artificial saliva for 42 days, and the degree of conversion during polymerisation was analysed using Fourier Transform Infra-red (FTIR) spectroscopy. RESULTS The flexural strength of the material significantly increased (p < 0.05) when the printing orientation was changed from 0° to 90°. A similar increase was observed in the hardness, degree of conversion, and water sorption results. In general, no significant difference (p > 0.05) in any of the tested properties was found when the post-curing times were increased from 20 to 50 min. SIGNIFICANCE The highest physical and mechanical properties of the 3D-printed denture base resin can be obtained by printing vertically (90° angle to the platform base). The minimal post-curing time to achieve ideal results is 30 min, as further curing will have no significant effect on the properties of the material.
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Affiliation(s)
- Ahmed Altarazi
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, United Kingdom; Restorative Dental Science, College of Dentistry, Taibah University, Saudi Arabia.
| | - Julfikar Haider
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, United Kingdom; Department of Engineering, Manchester Metropolitan University, Manchester, United Kingdom
| | - Abdulaziz Alhotan
- Dental Health Department, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Nick Silikas
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, United Kingdom.
| | - Hugh Devlin
- Division of Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, United Kingdom
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Effect of Printing Layer Thickness and Postprinting Conditions on the Flexural Strength and Hardness of a 3D-Printed Resin. BIOMED RESEARCH INTERNATIONAL 2022; 2022:8353137. [PMID: 35237691 PMCID: PMC8885203 DOI: 10.1155/2022/8353137] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 01/17/2022] [Accepted: 01/27/2022] [Indexed: 01/11/2023]
Abstract
Background Recently, dentists can utilize three-dimensional printing technology in fabricating dental restoration. However, to date, there is a lack of evidence regarding the effect of printing layer thicknesses and postprinting on the mechanical properties of the 3D-printed temporary restorations with the additive manufacturing technique. So, this study evaluated the mechanical properties of a 3D-printed dental resin material with different printing layer thicknesses and postprinting methods. Methods 210 specimens of a temporary crown material (A2 EVERES TEMPORARY, SISMA, Italy) were 3D-printed with different printing layer thicknesses (25, 50, and 100 μm). Then, specimens were 3D-printed using DLP technology (EVERES ZERO, DLP 3D printer, SISMA, Italy) which received seven different treatment conditions after printing: water storage for 24 h or 1 month, light curing or heat curing for 5 or 15 minutes, and control. Flexural properties were evaluated using a three-point bending test on a universal testing machine (ISO standard 4049). The Vickers hardness test was used to evaluate the microhardness of the material system. The degree of conversion was measured using an FT-IR ATR spectrophotometer. Statistical analysis was performed using two-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) test (p ≤ 0.05). Results The 100 μm printing layer thickness had the highest flexural strength among the other thickness groups. As a combined effect printing thickness and postprinting conditions, the 100 μm with the dry storage group has the highest flexural strength among the tested groups (94.60 MPa). Thus, the group with 100 μm thickness that was heat cured for 5 minutes (HC 5 min 100 μm) has the highest VHN value (VHN = 17.95). Also, the highest mean DC% was reported by 50 μm layer thickness (42.84%). Conclusions The thickness of the 100 μm printing layer had the highest flexural strength compared to the 25 μm and 50 μm groups. Also, the postprinting treatment conditions influenced the flexural strength and hardness of the 3D-printed resin material.
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GIBREEL M, PEREA-LOWERY L, VALLITTU PK, GAROUSHI S, LASSILA L. Two-body wear and surface hardness of occlusal splint materials. Dent Mater J 2022; 41:916-922. [DOI: 10.4012/dmj.2022-100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Mona GIBREEL
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| | - Leila PEREA-LOWERY
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| | | | - Sufyan GAROUSHI
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| | - Lippo LASSILA
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
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Which Three-Dimensional Printing Technology Can Replace Conventional Manual Method of Manufacturing Oral Appliance? A Preliminary Comparative Study of Physical and Mechanical Properties. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app12010130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Three-dimensional printing technology is widely being adopted in the manufacturing of oral appliances. The purpose of this study was to determine the most suitable method of manufacturing oral appliances by comparing the physical and mechanical properties of various 3D printing methods with the conventional method. Experimental groups consisted of six 3D-printed specimens via FDM, two polyjets, SLS, SLA, and DLP, and the milling methods. The control group consisted of an acrylic resin specimen made by the conventional manual method. The water absorption and solubility, color stability, flexural strength, and surface hardness were tested and statistically analyzed. The FDM, SLS, and DLP methods exhibited comparable water absorption and solubility with the control group, and only the SLA method exhibited significantly higher water solubility than the control group. In terms of the color stability, only the milling method met the requirements of the allowable clinical range. The FDM, SLA, and DLP methods exhibited comparable flexural strength with the control group. The surface hardness of the PJ-2, DLP, and milling methods was acceptable for replacing conventional manual method. Therefore, the most suitable method of manufacturing oral appliances among the experimental groups was the DLP method in terms of its water absorption and solubility, flexural strength, and surface hardness.
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21
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Aati S, Akram Z, Shrestha B, Patel J, Shih B, Shearston K, Ngo H, Fawzy A. Effect of post-curing light exposure time on the physico-mechanical properties and cytotoxicity of 3D-printed denture base material. Dent Mater 2021; 38:57-67. [PMID: 34815094 DOI: 10.1016/j.dental.2021.10.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/17/2021] [Accepted: 10/29/2021] [Indexed: 12/14/2022]
Abstract
OBJECTIVE This study investigated the effect of post curing light exposure time on the physico-mechanical properties and cytotoxicity of a 3D-printed PMMA-based denture material in comparison to a conventional heat-cured alternative as a control. METHODS 3D-printed specimens were fabricated followed by post-curing for 0, 5, 10 or 20 min at 200 W and light wavelength range of 390-540 nm. Heat-cured specimens were fabricated using a standard protocol. Specimens were placed in artificial saliva at 37 ℃ for 48 h (immediate groups) and 6 months (aged group), then evaluated flexural strength/modulus, fracture toughness, microhardness, and degree of conversion. Water sorption and solubility was assessed after 28 days. Flexural strength, flexural modulus, and fracture toughness were tested through three-point bending tests, while the surface hardness was tested using Vickers's test. Fractured specimens were viewed by scanning electron microscope (SEM). Cytotoxicity in term of cell viability was evaluated using human oral fibroblasts. RESULTS Flexural strength/modulus, fracture toughness and surface hardness significantly improved with the increase in light curing time up to 20 min. The same pattern of improvement was found with degree of conversion, water sorption, solubility, and cell viability. There was no significant difference (p < 0.01) between heat-cured material and 3D specimens post-cured for 20 min in term of flexural strength/modulus, surface hardness, and degree of conversion at the two-storage time points. SIGNIFICANCE Generally, the physico-mechanical properties of the 3D-printed denture base material improve as post curing time increases up to 20 min which exhibited comparable performance as the conventional heat-cured control.
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Affiliation(s)
- Sultan Aati
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia; Dental Health Department, College of Applied Medical Sciences, King Saud University, Riyadh 11433, Saudi Arabia
| | - Zohaib Akram
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Barsha Shrestha
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Jainish Patel
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Benjamin Shih
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Kate Shearston
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Hien Ngo
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Amr Fawzy
- UWA Dental School, University of Western Australia, 17 Monash Avenue, Nedlands, WA 6009, Australia.
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Firlej M, Pieniak D, Niewczas AM, Walczak A, Domagała I, Borucka A, Przystupa K, Igielska-Kalwat J, Jarosz W, Biedziak B. Effect of Artificial Aging on Mechanical and Tribological Properties of CAD/CAM Composite Materials Used in Dentistry. MATERIALS 2021; 14:ma14164678. [PMID: 34443198 PMCID: PMC8400053 DOI: 10.3390/ma14164678] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/09/2021] [Accepted: 08/17/2021] [Indexed: 11/21/2022]
Abstract
With easy-to-process 3D printing materials and fast production, the quality of dental services can be improved. In the conventional procedure, the dentist makes temporary crowns directly in the patient’s mouth, e.g., from the most commonly used bis-acrylic composites. Temporary crowns made directly in the office without the use of CAD/CAM are often of inferior quality, which directly results in impaired hygiene, poorer masticatory mechanics, greater deposition of plaque, calculus and sediment, and may adversely affect periodontal and gum health. The mechanical strength, resistance to aging and abrasion of 3D printing materials are higher than those of the soft materials used in conventional methods. This translates into durability. The patient leaves the surgery with a restoration of higher utility quality compared to the conventional method. The objective of the paper was to determine the influence of aging in artificial saliva of AM (additive manufacturing) orthodontic composites on their functional properties. For the purpose of the study, fillings well-known worldwide were selected. These were traditional UV-curable resins (M I, M II, M III, M V) and a hybrid material based on a UV-curable resin (M VI). Samples were stored in artificial saliva at 37 ± 1 °C in a thermal chamber for 6 months. Indentation hardness, frictional tests and sliding wear measurements were conducted. A comparison between various materials was made. Descriptive statistics, degradation coefficients, H2E, Archard wear and specific wear rate were calculated. The Weibull statistical test for indentation hardness was performed and Hertzian contact stresses for the frictional association were calculated for unaged (M I, M II, M III, M V, M VI) and aged (M I AS, M II AS, M III AS, M V AS, M VI AS) samples. M I exhibited the lowest average hardness among the unaged materials, while M III AS had the lowest average hardness among the aged materials. Comparably low hardness was demonstrated by the M I AS material. The coefficient of friction values for the aged samples were found to be higher. The lowest wear value was demonstrated by the M I material. The wear resistance of most of the tested materials deteriorated after aging. The M VI AS material had the highest increase in wear. According to the results provided, not only the chemical composition and structure, but also aging have a great impact on the indentation hardness and wear resistance of the tested orthodontic materials.
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Affiliation(s)
- Marcel Firlej
- Department of Craniofacial Anomalies, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznan, Poland; (M.F.); (I.D.); (J.I.-K.); (B.B.)
| | - Daniel Pieniak
- Department of Mechanics and Machine Building, University of Economics and Innovations in Lublin, Projektowa 4, 20-209 Lublin, Poland;
| | - Agata M. Niewczas
- Departament of Conservative Dentistry with Endodontics, Medical University of Lublin, W. Chodźki 6, 20-093 Lublin, Poland;
| | - Agata Walczak
- Departament of Fire Technology the Main School of Fire Service, Faculty of Safety Engineering and Civil Protection, Slowackiego 52/54, 01-629 Warsaw, Poland; (A.W.); (W.J.)
| | - Ivo Domagała
- Department of Craniofacial Anomalies, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznan, Poland; (M.F.); (I.D.); (J.I.-K.); (B.B.)
| | - Anna Borucka
- Faculty of Security, Logistics and Management, Military University of Technology, gen. S. Kaliskiego 2, 00-908 Warsaw, Poland;
| | - Krzysztof Przystupa
- Department of Automation, Lublin University of Technology, Nadbystrzycka 36, 20-618 Lublin, Poland
- Correspondence:
| | - Joanna Igielska-Kalwat
- Department of Craniofacial Anomalies, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznan, Poland; (M.F.); (I.D.); (J.I.-K.); (B.B.)
| | - Wojciech Jarosz
- Departament of Fire Technology the Main School of Fire Service, Faculty of Safety Engineering and Civil Protection, Slowackiego 52/54, 01-629 Warsaw, Poland; (A.W.); (W.J.)
| | - Barbara Biedziak
- Department of Craniofacial Anomalies, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznan, Poland; (M.F.); (I.D.); (J.I.-K.); (B.B.)
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Hada T, Kanazawa M, Iwaki M, Katheng A, Minakuchi S. Comparison of Mechanical Properties of PMMA Disks for Digitally Designed Dentures. Polymers (Basel) 2021; 13:polym13111745. [PMID: 34073564 PMCID: PMC8199238 DOI: 10.3390/polym13111745] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/18/2021] [Accepted: 05/18/2021] [Indexed: 12/03/2022] Open
Abstract
In this study, the physical properties of a custom block manufactured using a self-polymerizing resin (Custom-block), the commercially available CAD/CAM PMMA disk (PMMA-disk), and a heat-polymerizing resin (Conventional PMMA) were evaluated via three different tests. The Custom-block was polymerized by pouring the self-polymerizing resin into a special tray, and Conventional PMMA was polymerized with a heat-curing method, according to the manufacturer’s recommended procedure. The specimens of each group were subjected to three-point bending, water sorption and solubility, and staining tests. The results showed that the materials met the requirements of the ISO standards in all tests, except for the staining tests. The highest flexural strength was exhibited by the PMMA-disk, followed by the Custom-block and the Conventional PMMA, and a significant difference was observed in the flexural strengths of all the materials (p < 0.001). The Custom-block showed a significantly higher flexural modulus and water solubility. The water sorption and discoloration of the Custom-block were significantly higher than those of the PMMA-disk, but not significantly different from those of the Conventional PMMA. In conclusion, the mechanical properties of the three materials differed depending on the manufacturing method, which considerably affected their flexural strength, flexural modulus, water sorption and solubility, and discoloration.
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Affiliation(s)
- Tamaki Hada
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan; (T.H.); (A.K.); (S.M.)
| | - Manabu Kanazawa
- Digital Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
- Correspondence: ; Tel.: +81-3-5803-5379
| | - Maiko Iwaki
- General Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan;
| | - Awutsadaporn Katheng
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan; (T.H.); (A.K.); (S.M.)
| | - Shunsuke Minakuchi
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan; (T.H.); (A.K.); (S.M.)
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Prpić V, Schauperl Z, Glavina D, Ćatić A, Čimić S. Comparison of shear bond strengths of different types of denture teeth to different denture base resins. J Adv Prosthodont 2021; 12:376-382. [PMID: 33489022 PMCID: PMC7790604 DOI: 10.4047/jap.2020.12.6.376] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/12/2020] [Accepted: 12/09/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To determine the shear bond strengths of different denture base resins to different types of prefabricated teeth (acrylic, nanohybrid composite, and cross-linked) and denture teeth produced by computer-aided design/computer-aided manufacturing (CAD/CAM) technology. MATERIALS AND METHODS Prefabricated teeth and CAD/CAM (milled) denture teeth were divided into 10 groups and bonded to different denture base materials. Groups 1-3 comprised of different types of prefabricated teeth and cold-polymerized denture base resin; groups 4-6 comprised of different types of prefabricated teeth and heat-polymerized denture base resin; groups 7-9 comprised of different types of prefabricated teeth and CAD/CAM (milled) denture base resin; and group 10 comprised of milled denture teeth produced by CAD/CAM technology and CAD/CAM (milled) denture base resin. A universal testing machine was used to evaluate the shear bond strength for all specimens. One-way ANOVA and Tukey post-hoc test were used for analyzing the data (α=.05). RESULTS The shear bond strengths of different groups ranged from 3.37 ± 2.14 MPa to 18.10 ± 2.68 MPa. Statistical analysis showed significant differences among the tested groups (P<.0001). Among different polymerization methods, the lowest values were determined in cold-polymerized resin.There was no significant difference between the shear bond strength values of heat-polymerized and CAD/CAM (milled) denture base resins. CONCLUSION Different combinations of materials for removable denture base and denture teeth can affect their bond strength. Cold-polymerized resin should be avoided for attaching prefabricated teeth to a denture base. CAD/CAM (milled) and heat-polymerized denture base resins bonded to different types of prefabricated teeth show similar shear bond strength values.
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Affiliation(s)
- Vladimir Prpić
- School of Dental Medicine, University of Zagreb, Zagreb, Croatia
| | - Zdravko Schauperl
- Department of Materials, Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Zagreb, Croatia
| | - Domagoj Glavina
- Department of Pediatric and Preventive Dentistry, School of Dental Medicine, University of Zagreb, Zagreb, Croatia
| | - Amir Ćatić
- Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Zagreb, Croatia
| | - Samir Čimić
- Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Zagreb, Croatia
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Grymak A, Aarts JM, Ma S, Waddell JN, Choi JJE. Comparison of hardness and polishability of various occlusal splint materials. J Mech Behav Biomed Mater 2020; 115:104270. [PMID: 33341739 DOI: 10.1016/j.jmbbm.2020.104270] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/06/2020] [Accepted: 12/10/2020] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To measure polishability of occlusal splint materials manufactured by various methods. METHODS Seven occlusal splint materials manufactured by four different methods - Heat cured (Vertex Rapid simplified Clear), CAD-milled (Ceramill a-splint), Vacuum-formed (Proform splint) and 3D-printed (Freeprint Ortho, KeySplint Soft, DentaClear and FreePrint Splint 2.0) were tested for gloss, roughness, and surface hardness and elastic modulus. For all groups, the tests were repeated with the materials polished with three different polishing burs, pumice and high shine. All polishing procedures were standardised by applying the force of 1 N for 1 min at the set speed. 3D printed materials were further tested with additional specimens manufactured at different printing angles of 0°, 45° and 90°. Data was statistically analysed using ANOVA (SPSS Version 26) and MatLab (R2020a). Polished surfaces of each specimen were analysed under scanning electron microscope. RESULTS Vacuum-formed materials showed the highest polishability (80.61 ± 0.98 GU) with no statistical significance to heat-cured or CAD-milled (p = 1.00). Pumice and high shine polish significantly improved the gloss for all groups. The mean gloss and surface roughness for all 3D-printed materials ranged from 75.24 ± 25.05 GU to 0.18 ± 0.21 GU and 2.73 ± 3.18 μm to 0.06 ± 0.01 μm, which was significantly lower (p < 0.001) than heat-cured, CAD-milled and vacuum-formed materials. The highest hardness (0.40 ± 0.009 GPa), elastic modulus (6.06 ± 1.49 GPa) and gloss were found when materials were 3D-printed at 45°, with the lowest surface roughness. CONCLUSION Statistically significant differences in polishability were found among the different occlusal splint materials. The polishability and surface hardness of 3D-printed occlusal splint materials was influenced by the print angle. The 0° 3D-printed occlusal splint materials produced the highest gloss and the lowest surface roughness pre-polished, indicating that no polishing is required. While the 3D-printed occlusal splint materials at 45oand 90° required polishing with burs, pumice and high shine to reduce the surface roughness, there were layering structures created during printing.
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Affiliation(s)
- Anastasiia Grymak
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, New Zealand
| | - John M Aarts
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, New Zealand
| | - Sunyoung Ma
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, New Zealand
| | - John Neil Waddell
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, New Zealand
| | - Joanne Jung Eun Choi
- Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, New Zealand.
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Domagała I, Przystupa K, Firlej M, Pieniak D, Niewczas A, Biedziak B. Bending Behaviour of Polymeric Materials Used on Biomechanics Orthodontic Appliances. MATERIALS 2020; 13:ma13235579. [PMID: 33297572 PMCID: PMC7731210 DOI: 10.3390/ma13235579] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 11/28/2020] [Accepted: 12/04/2020] [Indexed: 02/06/2023]
Abstract
This paper discusses the issues of strength and creep of polymeric materials used in orthodontic appliances. Orthodontic biomechanics is focused on the movement of individual teeth or dental groups as a result of the force applied by orthodontic appliances. Stresses in the construction of functional and biomechanical appliances is generated when using the apparatus in the oral cavity. The orthodontic appliance must maintain its shape and not be damaged during treatment so strength and creep resistance are fundamental properties. It was assumed that the clinical success of orthodontic appliances can be determined by these performance properties. The aim of the work was the experimental assessment of comparative bending strength and creep resistance of selected popular polymer materials used in the production of biomechanical orthodontic appliances. Four commercial materials manufactured by the world class producers were tested: NextDent Ortho Rigid (Vertex-Dental B.V., Soesterberg, The Netherlands) marked as "1A"; Erkocryl (ERKODENT Erich Kopp GmbH, Pfalzgrafenweiler, Germany)-"2A"; Vertex Orthoplast (Vertex Dental B.V.), blue, marked as "3A" and material with the same name as "3A" but orange, marked in the article as "4A". All the tests were carried out after aging in artificial saliva for 48 h at a temperature of 37 °C. Flexular strength and flexular modulus were made using the three point bending method according to the ISO 178 technical standard. Creep tests were carried out according to the method contained in ISO 899-2. The creep test was carried out in an artificial saliva bath at 37 °C. The creep tests showed significant differences in the strength, modulus and deformability of the tested materials. The strength reliability of the tested materials also varied. The research shows that the 2A material can be used for orthodontic applications in which long-term stresses should be lower than 20 MPa.
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Affiliation(s)
- Ivo Domagała
- Department of Facial Malformations, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznań, Poland; (I.D.); (M.F.); (B.B.)
| | - Krzysztof Przystupa
- Department of Automation, Lublin University of Technology, Nadbystrzycka 36, 20-618 Lublin, Poland
- Correspondence:
| | - Marcel Firlej
- Department of Facial Malformations, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznań, Poland; (I.D.); (M.F.); (B.B.)
| | - Daniel Pieniak
- Department of Mechanics and Machine Building, University of Economics and Innovations in Lublin, Projektowa 4, 20-209 Lublin, Poland;
| | - Agata Niewczas
- Department of Conservative Dentistry with Endodontics, Medical University of Lublin, Karmelicka 7, 20-080 Lublin, Poland;
| | - Barbara Biedziak
- Department of Facial Malformations, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznań, Poland; (I.D.); (M.F.); (B.B.)
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Wesemann C, Spies BC, Sterzenbach G, Beuer F, Kohal R, Wemken G, Krügel M, Pieralli S. Polymers for conventional, subtractive, and additive manufacturing of occlusal devices differ in hardness and flexural properties but not in wear resistance. Dent Mater 2020; 37:432-442. [PMID: 33288324 DOI: 10.1016/j.dental.2020.11.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/19/2020] [Accepted: 11/27/2020] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To investigate the wear resistance of polymers for injection molding, subtractive and additive manufacturing of occlusal devices in comparison with enamel antagonist wear and material properties (i.e., hardness, flexural strength, and flexural modulus). METHODS Injection molding was compared with milling and the additive technologies stereolithography, low force stereolithography, and digital light processing. For each material, eight specimens were produced for wear measurements. Extracted human premolars served as indenters. All samples were subjected to two series of a 2-body wear test consisting of 200,000 circular loading cycles with an applied load of 1) 20 N and 2) 50 N in a thermocycling environment (5/55 °C, 30 s, 3860 cycles, H2O). Wear resistance was characterized by means of maximum depth and volume of the resulting traces. In addition, enamel wear of the indenters and Vickers hardness, flexural strength, and flexural modulus of the polymers were determined. Wear was statistically analyzed with linear general models for repeated measures and material properties with one-way ANOVA with post-hoc Tukey-HSD tests. RESULTS Wear of the antagonists was not influenced by the material (P ≥ 0.343). Likewise, no differences in wear resistance were found between materials after cyclic loading with 20 N or 50 N (P ≥ 0.074). Material properties investigated revealed decreased values for the resins for the additive manufacturing with the exception of flexural strength of one material. SIGNIFICANCE Within the limitations of this in-vitro study, arylates for conventional, subtractive, and additive manufacturing of occlusal devices differ in material properties but not in wear resistance and antagonist wear.
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Affiliation(s)
- Christian Wesemann
- Medical Center - University of Freiburg, Center for Dental Medicine, Department of Prosthetic Dentistry, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany; Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Assmanshauser Str. 4-6, 14197 Berlin, Germany
| | - Benedikt Christopher Spies
- Medical Center - University of Freiburg, Center for Dental Medicine, Department of Prosthetic Dentistry, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany.
| | - Guido Sterzenbach
- Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Assmanshauser Str. 4-6, 14197 Berlin, Germany
| | - Florian Beuer
- Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Assmanshauser Str. 4-6, 14197 Berlin, Germany
| | - Ralf Kohal
- Medical Center - University of Freiburg, Center for Dental Medicine, Department of Prosthetic Dentistry, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany
| | - Gregor Wemken
- Medical Center - University of Freiburg, Center for Dental Medicine, Department of Prosthetic Dentistry, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany
| | - Marei Krügel
- Medical Center - University of Freiburg, Center for Dental Medicine, Department of Prosthetic Dentistry, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany
| | - Stefano Pieralli
- Medical Center - University of Freiburg, Center for Dental Medicine, Department of Prosthetic Dentistry, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany
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Hada T, Kanazawa M, Iwaki M, Arakida T, Minakuchi S. Effect of printing direction on stress distortion of three-dimensional printed dentures using stereolithography technology. J Mech Behav Biomed Mater 2020; 110:103949. [DOI: 10.1016/j.jmbbm.2020.103949] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/18/2020] [Accepted: 06/21/2020] [Indexed: 11/28/2022]
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Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry. J Prosthet Dent 2020; 124:274-349. [PMID: 32811666 DOI: 10.1016/j.prosdent.2020.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 01/20/2023]
Abstract
This comprehensive review of the 2019 restorative dental literature is offered to inform busy dentists regarding remarkable publications and noteworthy progress made in the profession. Developed by the Scientific Investigation Committee of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to 1 of 8 sections of the report: (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information likely to influence day-to-day dental treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source material when greater detail is desired. As the profession moves toward evidence-based clinical decision-making, an incredible volume of potentially valuable dental literature continues to increase. It is the intention of this review and its authors to provide assistance in negotiating the extensive dental literature published in 2019. It is our hope that readers find this work useful in the clinical management of dental patients.
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Reymus M, Stawarczyk B. In vitro study on the influence of postpolymerization and aging on the Martens parameters of 3D-printed occlusal devices. J Prosthet Dent 2020; 125:817-823. [PMID: 32444206 DOI: 10.1016/j.prosdent.2019.12.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 12/30/2019] [Accepted: 12/30/2019] [Indexed: 11/15/2022]
Abstract
STATEMENT OF PROBLEM Additive manufacturing has been proposed for the fabrication of occlusal devices. However, information about the mechanical properties of additively manufactured devices is lacking. PURPOSE The purpose of this in vitro study was to evaluate the influence of the postpolymerization unit and artificial aging on the Martens hardness (HM) and indentation modulus (EIT) of different 3D-printed materials in comparison with a conventionally milled material. MATERIAL AND METHODS Thirty disks (20 mm in diameter and 5 mm in thickness) were additively manufactured (D20 II, Rapidshape & Form 2) for each 3D-printed material (NextDent Splint, Formlabs Dental LT Clear, and Freeprint Splint). As a control, 10 disks of the same thickness were cut from a conventionally milled material (Temp Premium). Each specimen was measured for HM and EIT (ZHU 0,2) after fabrication. The specimens were stored in water at 37 °C and measured again after 2 and 4 weeks. The data were analyzed statistically by using the Kruskal-Wallis, Mann-Whitney U, and Wilcoxon tests (adjusted by Bonferroni correction α=.05/27=.002). RESULTS The highest influence on HM parameters was shown by artificial aging (partial eta squared: HM: ηP2=0.840, EIT: ηP2=0.855, P<.001), followed by the material (HM: ηP2=0.690 EIT: ηP2=0.845, P<.001) and the postpolymerization unit (HM: ηP2=0.649, EIT: ηP2=0.778, P<.001). Initial HM values ranged from 147 ±8.11 N/mm2 for Formlabs postpolymerized in Otoflash to 89.5 ±8.55 N/mm2 for Detax postpolymerized in the Labolight unit. EIT values ranged from 3.92 ±0.061 kN/mm2 for Formlabs postpolymerized in Otoflash to 2.48 ±0.212 kN/mm2 for Detax postpolymerized in the Labolight unit. In general, HM and EIT values decreased after water storage, whereas the values remained unchanged for the control group. CONCLUSIONS HM parameters of additively manufactured occlusal devices depend on postpolymerization strategy. Otoflash and Printbox result in higher HM and EIT values. The 3D-printed materials are more prone to artificial aging than the control group, which brings into question their long-term service.
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Affiliation(s)
- Marcel Reymus
- Resident, Department of Conservative Dentistry and Periodontology, University Hospital, LMU Munich, Munich, Germany.
| | - Bogna Stawarczyk
- Professor, Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
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31
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Hada T, Suzuki T, Minakuchi S, Takahashi H. Reduction in maxillary complete denture deformation using framework material made by computer-aided design and manufacturing systems. J Mech Behav Biomed Mater 2019; 103:103514. [PMID: 31778908 DOI: 10.1016/j.jmbbm.2019.103514] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 11/19/2022]
Abstract
The aim of this study was to investigate the effects of framework materials manufactured by dental CAD/CAM systems on complete denture deformation. Four materials were used for the maxillary complete denture framework: fiber-reinforced composite (FRC), nano-zirconia (N-Zr), cobalt-chromium-molybdenum alloy (CCM), and polyether-ether-ketone (PEEK). The framework materials were prepared using CAD/CAM systems. Six dentures of each material were fabricated, using polymethyl-methacrylate (PMMA) as a control. The thickness of the palatal area was 1.0 mm for PMMA and PEEK and 0.5 mm for FRC, N-Zr, and CCM. The denture deformation during occlusal load was monitored using four rosette strain gauges placed on the midline of the denture. The maximum principal strain (MPS) of each gauge, except that at the labial frenum, increased proportionally with increasing applied load. The directions of MPS were predominantly perpendicular to the midline of the denture. When a 200-N load was applied, the MPS at the incisive papilla in N-Zr and CCM was half that of PMMA; there was no significant difference among MPSs of PEEK, PMMA and FRC. The MPS at the end point of the denture in FRC, N-Zr, and CCM was significantly smaller than that of PMMA. The MPSs of the complete denture decreased when the CAD/CAM fabricated framework was used. The effects of the CAD/CAM fabricated framework on complete denture deformation varied due to the material used; however, a CAD/CAM fabricated framework material is considered to be effective for reducing complete denture deformation.
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Affiliation(s)
- Tamaki Hada
- Department of Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Tetsuya Suzuki
- Department of Oral Prosthetic Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Shunsuke Minakuchi
- Department of Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Hidekazu Takahashi
- Department of Oral Biomaterials Development Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
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Surface roughness and wear behavior of occlusal splint materials made of contemporary and high-performance polymers. Odontology 2019; 108:240-250. [PMID: 31612354 DOI: 10.1007/s10266-019-00463-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 09/16/2019] [Indexed: 10/25/2022]
Abstract
With the development of a digital technology of computer-assisted manufacturing (CAD/CAM) and new age materials, the use of new types of occlusal splint is to consider. The aim of the present study was to evaluate the surface roughness (Ra) and wear behavior of different CAD/CAM materials against enamel antagonist through a simulated chewing test. A total of 75 specimens made from ethylene vinyl acetate (EVA), polymethyl methacrylate (PMMA), polycarbonate (PC), polyetheretherketone (PEEK), and polyethyleneterephthalate (PETG) as a control were polished to evaluate the Ra before loading by optical profilometry and further analyzed by scanning electron microscopy (SEM). Specimens of each group were subjected to thermomechanical fatigue loading in a chewing simulator (60000 cycles at 49 N with 5-55 °C thermocycling). The wear volume loss and change in Ra of each specimen after the simulated chewing were analyzed. One-way ANOVA, paired samples t test, and Pearson correlation analysis were performed for statistical analyzes. The result showed that the volume loss and Ra varied among the materials tested. EVA exhibited the greatest amount of Ra and volume loss (p < 0.001), while PEEK had the lowest values for both (p < 0.001). In terms of volume loss, there was no significant difference between PC and PMMA (p > 0.05). SEM investigations revealed different wear behaviors, especially in EVA. As PEEK showed significantly more favorable results, PEEK splints should be considered as a new therapeutic option for occlusal splint.
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