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Yilmaz AD, Okutan Y. Effect of air-abrasion at pre- and/or post-sintered stage and hydrothermal aging on surface roughness, phase transformation, and flexural strength of multilayered monolithic zirconia. J Biomed Mater Res B Appl Biomater 2020; 109:606-616. [PMID: 33236475 DOI: 10.1002/jbm.b.34760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 10/27/2020] [Accepted: 11/10/2020] [Indexed: 11/08/2022]
Abstract
This study aimed to evaluate the effect of air-abrasion/sintering order and autoclave aging on the surface roughness (Ra), phase transformation, and biaxial flexural strength (BFS) of monolithic zirconia. A total of 104 monolithic zirconia specimens (Katana ML) were divided into eight groups according to airborne-particle abrasion protocols and hydrothermal aging: control (non-aged: C-, aged: C+), air-abrasion before sintering (BS-, BS+), air-abrasion after sintering (AS-, AS+), and air-abrasion before and after sintering (BAS-, BAS+). A steam autoclave was used for accelerated aging, and Ra values were measured with a surface profilometer. All specimens were analyzed by X-ray diffraction to determine any phase transformation on the zirconia surface. BFS was measured by using the piston-on-three-balls method. Scanning electron microscopy and atomic force microscopy were performed on one specimen per group. BS and BAS groups showed higher Ra values compared with groups C and AS. The aging process significantly increased the monoclinic phase content of all specimens. Lower monoclinic levels were found in AS+ and BAS+ compared with other aged groups. The AS groups exhibited higher flexural strength values relative to control groups, whereas BS groups exhibited significantly lower flexural strength values (p < .05). There was no reduction in flexural strength by using the BAS protocol. Air-abrasion of zirconia at the pre-sintered stage only is not recommended in clinical use because of the remarkable decrease in flexural strength.
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Affiliation(s)
- Ali Dogus Yilmaz
- Department of Prosthodontics, Canakkale Oral and Dental Health Center, Canakkale, Turkey
| | - Yener Okutan
- Faculty of Dentistry, Department of Prosthodontics, Aydın Adnan Menderes University, Aydın, Turkey
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Saker S, Özcan M. Effect of surface finishing and polishing procedures on color properties and translucency of monolithic zirconia restorations at varying thickness. J ESTHET RESTOR DENT 2020; 33:953-963. [PMID: 33188586 DOI: 10.1111/jerd.12681] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/12/2020] [Indexed: 11/29/2022]
Abstract
OBJECTIVE This study aimed to assess the impact of monolithic zirconia thickness on its color properties after different surface finishing and polishing procedures, and following aging in coffee solution. MATERIALS AND METHODS Two types of monolithic zirconia brands [Prettau Anterior (PA) and DD Cubex2 (DDC)] with three different thicknesses: 0.5, 1, and 1.5, and 10 mm diameter were tested. The color properties were evaluated after various surface finishing procedures (glazing, adjusting with burs + glaze, polishing, adjusting with burs + polishing) and after 5,000 cycles in a coffee solution were evaluated. The differences in color (ΔE) and translucency, were calculated and statistically analyzed by three-way ANOVA and pairwise comparison (α = 0.05). RESULTS The brand, material thickness, and surface finishing protocol before and after coffee thermocycling had significant effect on color variations (p < 0.001). For translucency, 3-way ANOVA revealed a significant interaction between the material thickness and surface finishing protocol following aging in coffee solution (p < 0.001), however no significant interaction was observed following the surface finishing protocols (p = 0.247). CONCLUSIONS The optical properties of monolithic zirconia ceramics can be influenced by the material brand, material thickness and the procedure of surface finishing and polishing. CLINICAL SIGNIFICANCE Clinicians should take into consideration the potential change of the color properties of monolithic zirconia restorations following both contouring and occlusal adjustment procedures and coffee intake.
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Affiliation(s)
- Samah Saker
- Department of Fixed Prosthodontics, Mansoura University, Mansoura, Egypt
| | - Mutlu Özcan
- Division of Dental Biomaterials, Center for Dental and Oral Medicine, Clinic for Reconstructive Dentistry, University of Zürich, Zürich, Switzerland
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DE SOUZA RH, KAIZER MR, BORGES CEP, FERNANDES ABF, CORRER GM, DIÓGENES AN, ZHANG Y, GONZAGA CC. Flexural strength and crystalline stability of a monolithic translucent zirconia subjected to grinding, polishing and thermal challenges. CERAMICS INTERNATIONAL 2020; 46:26168-26175. [PMID: 33716378 PMCID: PMC7946154 DOI: 10.1016/j.ceramint.2020.07.114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The objective of this study is to investigate the magnitude of structural degradation of a monolithic translucent zirconia caused by clinically relevant grinding and polishing procedures, when associated or not with low temperature degradation (LTD), induced by accelerated hydrothermal aging using autoclave or thermocycling Ninety disks (Ø12 × 1 mm) were prepared from dental zirconia for monolithic restorations (Vipi Block Zirconn Translucent, Vipi). The specimens were divided into 3 groups (n = 30) according to surface treatment: As Sintered (untreated), Grind (diamond bur), Grind + Polish (diamond bur + polish); and then subdivided according to aging method (n = 10): Baseline (no aging), Autoclave (134°C, 2.2 kgf/cm2 pressure for 5 h), and Thermocycling (200,000 cycles, 5°C and 55°C, for 15 s each). Roughness, biaxial flexural strength and percentage of monoclinic phase were evaluated. Regarding surface treatment, the Grind group presented higher roughness and greater flexural strength compared to As Sintered group, while Grind + Polish showed intermediate roughness and flexural strength similar to Grind group. Aging had little effect on roughness, but yielded a significant reduction in flexural strength. Tetragonal to monoclinic phase transformation was observed in all groups, caused by both mechanical stresses (grinding and polishing) and LTD, which was similarly induced by the traditional autoclave method, as well as the thermocycling method The use of diamond burs to grind zirconia surface may result in deleterious effects on the surface quality of monolithic zirconia restorations, yet has a potential toughening effect by phase transformation. However, when zirconia is exposed to LTD, regardless of the surface treatment, degradation of the surface quality and strength are observed.
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Affiliation(s)
- Raisa Hintz DE SOUZA
- School of Health Sciences, Graduate Program in Dentistry, Universidade Positivo, Curitiba, PR 81280, Brazil
| | - Marina R KAIZER
- School of Health Sciences, Graduate Program in Dentistry, Universidade Positivo, Curitiba, PR 81280, Brazil
| | | | | | - Gisele Maria CORRER
- School of Health Sciences, Graduate Program in Dentistry, Universidade Positivo, Curitiba, PR 81280, Brazil
| | | | - Yu ZHANG
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY 10010, USA
| | - Carla Castiglia GONZAGA
- School of Health Sciences, Graduate Program in Dentistry, Universidade Positivo, Curitiba, PR 81280, Brazil
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Skjold A, Schriwer C, Gjerdet NR, Øilo M. Effect of artificial aging on high translucent dental zirconia: simulation of early failure. Eur J Oral Sci 2020; 128:526-534. [PMID: 33058363 DOI: 10.1111/eos.12739] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/04/2020] [Accepted: 09/10/2020] [Indexed: 01/02/2023]
Abstract
Higher yttria content enhances the translucency and appearance of dental zirconia materials. Alterations in material composition also affect mechanical properties. The aim of this study was to compare the fracture load after artificial short-term aging of monolithic, full-contour zirconia crowns with different amounts of yttria-stabilization. Sixty crowns (thirty super high translucent crowns (5Y-Z) and thirty high translucent crowns (3Y-Z)) were produced to fit a model of a premolar with a shallow chamfer preparation. The crowns were cemented with self-adhesive resin cement on composite abutments. For each zirconia type, three groups of crowns (n = 10) were allocated to: (i) cyclic loading (200 N, 1 Hz, 30,000 cycles), (ii) hydrothermal aging (3 × 20 min, 134°C 3.2 bar), or (iii) no treatment (control). Surviving crowns from the aging process were quasistatically loaded until fracture. The 3Y-Z crowns had statistically significantly higher fracture values (3,449 N) than the 5Y-Z crowns (1,938 N). The aging procedures did not affect load at fracture. Fractographic analysis showed that fractures started either at the crown margin or at the occlusal intaglio area. Higher yttria content leads to a reduction in material strength and damage tolerance, and this should be reflected in recommendations for clinical use.
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Affiliation(s)
- Anneli Skjold
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Christian Schriwer
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Nils R Gjerdet
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Marit Øilo
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
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Study of the Effect of Low-Energy Irradiation with O2+ Ions on Radiation Hardening and Modification of the Properties of Thin TiO2 Films. J Inorg Organomet Polym Mater 2020. [DOI: 10.1007/s10904-020-01787-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Microstructural, mechanical, and optical characterization of an experimental aging-resistant zirconia-toughened alumina (ZTA) composite. Dent Mater 2020; 36:e365-e374. [PMID: 32943230 DOI: 10.1016/j.dental.2020.08.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 07/05/2020] [Accepted: 08/29/2020] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To evaluate the effect of aging on the microstructural, mechanical, and optical properties of an experimental zirconia-toughened alumina composite with 80%Al2O3 and 20%ZrO2 (ZTA Zpex) compared to a translucent zirconia (Zpex) and Alumina. METHODS Disc-shaped specimens were obtained by uniaxial and isostatic pressing the synthesized powders (n = 70/material). After sintering and polishing, half of the specimens underwent aging (20 h, 134 °C, 2.2 bar). Crystalline content and microstructure were evaluated using X-ray diffraction and scanning electron microscopy, respectively. Specimens underwent biaxial flexural strength testing to determine the characteristic stress, Weibull modulus, and reliability. Translucency parameter (TP) and Contrast ratio (CR) were calculated to characterize optical properties. RESULTS ZTA Zpex demonstrated a compact surface with a uniform dispersion of zirconia particles within the alumina matrix, and typical alumina and zirconia crystalline content. ZTA Zpex and alumina exhibited higher CR and lower TP than Zpex. ZTA Zpex and Zpex showed significantly higher characteristic stress relative to alumina. While aging did not affect optical and mechanical properties of ZTA Zpex and alumina, Zpex demonstrated a significant increase in translucency, as well as a in characteristic stress. Alumina reliability was significantly lower than others at 300 MPa, ZTA Zpex and Zpex reliability decreased at 800 MPa, except for aged Zpex. SIGNIFICANCE While aging did not affect the mechanical nor the optical properties of ZTA Zpex and alumina, it did alter both properties of Zpex. The results encourage further investigations to engineer ZTA as a framework material for long span fixed dental prostheses specially where darkened substrates, such as titanium implant abutments or endodontically treated teeth, demand masking.
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de Araújo-Júnior ENS, Bergamo ETP, Campos TMB, Benalcázar Jalkh EB, Lopes ACO, Monteiro KN, Cesar PF, Tognolo FC, Tanaka R, Bonfante EA. Hydrothermal degradation methods affect the properties and phase transformation depth of translucent zirconia. J Mech Behav Biomed Mater 2020; 112:104021. [PMID: 32882676 DOI: 10.1016/j.jmbbm.2020.104021] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/28/2020] [Accepted: 07/31/2020] [Indexed: 02/04/2023]
Abstract
OBJECTIVES To characterize the optical and mechanical properties of a commercial and in-house translucent Y-TZP before and after aging in autoclave or hydrothermal reactor. METHODS In-house experimental discs were obtained through uniaxial and isostatic pressing a translucent Y-TZP powder and sintering at 1,550 °C/1 h. Commercial discs were milled from pre-sintered blocks fabricated with the same powder through uniaxial and isostatic pressing and sintering. Discs were allocated into three groups according to aging condition: immediate, aged via autoclave, or reactor (134 °C, 20 h, 2.2 bar). Crystalline content and microstructure were evaluated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Residual compressive stress (CS) was determined by Raman spectroscopy. Optical properties were determined by the contrast ratio (CR) and translucency parameter (TP) using reflectance data. Mechanical properties were assessed by Vickers hardness, fracture toughness and biaxial flexural strength tests. RESULTS XRD and SEM revealed a typical Y-TZP crystalline content, chiefly tetragonal phase, and a dense crystalline matrix for both processing protocols. Reactor aging triggered a more pronounced t-m transformation relative to autoclave. In-house and commercial Y-TZPs demonstrated similar CR and TP, with reactor aging significantly increasing their translucency. Similarly, reactor aging influenced Vickers hardness and fracture toughness. In-house processed Y-TZP clearly demonstrated the presence of CS, whereas commercial Y-TZP showed no presence of CS. Non-aged in-house Y-TZP resulted in significantly lower characteristic strength relative to commercial Y-TZP. While aging protocols significantly increased the characteristic strength of in-house Y-TZP, reactor significantly decreased commercial Y-TZP characteristic strength. Both Y-TZP processing protocols demonstrated high reliability at high-stress missions, with no detrimental effect of aging. CONCLUSIONS Laboratory aging methodology significantly influenced optical and mechanical properties of a commercial and in-house translucent Y-TZP.
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Affiliation(s)
- Everardo N S de Araújo-Júnior
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil.
| | - Edmara T P Bergamo
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Tiago M B Campos
- Department of Physics, Technological Institute of Aeronautics, São José Dos Campos, SP, Brazil
| | - Ernesto B Benalcázar Jalkh
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Adolfo C O Lopes
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Kelli N Monteiro
- Department of Biomaterials and Oral Biology, University of São Paulo, School of Dentistry, São Paulo, SP, Brazil
| | - Paulo F Cesar
- Department of Biomaterials and Oral Biology, University of São Paulo, School of Dentistry, São Paulo, SP, Brazil
| | - Fernanda C Tognolo
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Ricardo Tanaka
- TNK Lab, Rua João de Santa Maria, 129 - Jardim da Saúde - São Paulo, SP, Brazil
| | - Estevam A Bonfante
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
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Porojan L, Vasiliu RD, Bîrdeanu MI, Porojan SD. Surface Characterization and Optical Properties of Reinforced Dental Glass-Ceramics Related to Artificial Aging. Molecules 2020; 25:molecules25153407. [PMID: 32731378 PMCID: PMC7435760 DOI: 10.3390/molecules25153407] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/24/2020] [Accepted: 07/26/2020] [Indexed: 11/16/2022] Open
Abstract
The development of various dental glass-ceramic materials and the evolution of novel processing technologies lead to an essential change in the clinical and technical workflow. The long-term success of a dental restoration treatment is defined by its durability, which is directly influenced by the oral environment. This study's purpose was to evaluate the artificial aging behavior of nanostructured, respective microstructured ceramics related to surface topography, roughness, and optical properties. Six monolithic restoration materials were selected: milled lithium disilicate glass-ceramic (LDS-M) MT (medium translucency), hot-pressed lithium disilicate glass-ceramic (LDS-P) MT and HT (high translucency), milled zirconia-reinforced lithium silicate ceramic (ZLS-M) MT and hot-pressed zirconia-reinforced lithium silicate ceramic (ZLS-P) MT and HT, resulting n = 96 surfaces. All the samples were artificially aged by thermal cycling, and all investigations were made before and after thermal cycling. In terms of optical properties, differences recorded between ZLS and LDS ceramics are not significant. Thermal cycling increases the translucency of ZLS and LDS glass-ceramic materials significantly, with the most harmful effect on the pressed and polished samples. Micro- and nano roughness are significantly influenced by in vitro aging and a negative correlation was recorded. Glazed samples are characterized by significant rougher surfaces for all types of materials. On nanolevel, ZLS materials are significantly smoothed by thermal cycling.
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Affiliation(s)
- Liliana Porojan
- Department of Dental Prostheses Technology (Dental Technology), “Victor Babeș” University of Medicine and Pharmacy Timișoara, Romania, Eftimie Murgu Sq. no. 2, 300041 Timișoara, Romania;
| | - Roxana-Diana Vasiliu
- Department of Dental Prostheses Technology (Dental Technology), “Victor Babeș” University of Medicine and Pharmacy Timișoara, Romania, Eftimie Murgu Sq. no. 2, 300041 Timișoara, Romania;
- Correspondence: ; Tel.: +40-745225523
| | - Mihaela-Ionela Bîrdeanu
- National Institute for Research and Development in Electrochemistry and Condensed Matter, 300569 Timisoara, Romania;
| | - Sorin-Daniel Porojan
- Department of Oral Rehabilitation (Dental Technology), “Victor Babeș” University of Medicine and Pharmacy Timișoara, Romania, Eftimie Murgu Sq. no. 2, 300041 Timișoara, Romania;
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Dynamics of Radiation Damage in AlN Ceramics under High-Dose Irradiation, Typical for the Processes of Swelling and Hydrogenation. CRYSTALS 2020. [DOI: 10.3390/cryst10060546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The use of nitride ceramics, in particular AlN, as structural materials for nuclear power is primarily limited by their resistance to swelling and hydrogenation processes due to the accumulation of poorly soluble helium and hydrogen ions in the structure of the surface layer. In this regard, research in this area is of great importance not only from a fundamental point of view, but also practical, since any new data on radiation resistance can make a great contribution to the development of the theory of resistance to radiation influences of structural materials of a new generation. This work is devoted to a systematic study and comparative analysis of the dynamics of radiation damage during high-dose irradiation with protons and helium ions in nitride ceramics, which have great potential for use as structural materials for GenIV reactors. The choice of irradiation doses of 1 × 1017–5 × 1017 ion/cm2 is due to the possibility of modeling the processes of radiation damage characteristic of displacements of 10–50 dpa. During the study, the dependences of the change in the dielectric and conductive characteristics of nitride ceramics depending on the radiation dose, as well as on the type of ions, were established. The kinetics of degradation and accelerated aging was determined depending on the type of exposure. The mechanical and strength properties of ceramics were determined.
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Benalcazar Jalkh EB, Monteiro KN, Cesar PF, Genova LA, Bergamo ETP, Lopes ACDO, Lima E, Lisboa-Filho PN, Campos TMB, Witek L, Coelho PG, Borges AFS, Bonfante EA. Aging resistant ZTA composite for dental applications: Microstructural, optical and mechanical characterization. Dent Mater 2020; 36:1190-1200. [PMID: 32561117 DOI: 10.1016/j.dental.2020.05.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 05/03/2020] [Accepted: 05/24/2020] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To synthesize a zirconia toughened alumina (ZTA) composite with 70% alumina reinforced by 30% zirconia for dental applications and to characterize its microstructure and optical properties for comparison with the isolated counterpart materials and a first-generation 3Y-TZP. METHODS Disc-shaped specimens were divided in four groups (n = 70/material): (1) 3YSB-E (first generation 3Y-TZP), (2) Zpex (second generation 3Y-TZP), (3) alumina, and (4) ZTA-Zpex 70/30. After synthesis, ceramic powders were pressed, and green-body samples sintered following a predetermined protocol. Specimens were polished to obtain a mirror surface finish. Apparent density was measured by Archimedes principle. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the crystalline content and microstructure. Reflectance tests were performed to determine the contrast-ratio (CR) and translucency-parameter (TP). Mechanical properties were assessed by biaxial flexural strength (BFS) test. All analyses were conducted before and after artificial aging (20 h, 134 °C, 2.2 bar). Optical parameters were evaluated through repeated-measures analysis of variance and Tukey tests (p < 0.05). BFS data were analyzed using Weibull statistics (95% CI). RESULTS High density values (95-99%) were found for all ceramic materials and SEM images exhibited a dense microstructure. While XRD patterns revealed the preservation of crystalline content in the ZTA composite, an increase in the monoclinic peak was observed for pure zirconias after aging. Significantly higher CR and lower TP values were observed for the ZTA composite, followed by alumina, 3YSB-E, and Zpex. The highest characteristic stress was recorded for 3YSB-E, followed by intermediate values between ZTA and Zpex, and the lowest for alumina. Aging affected the optical and mechanical properties of both zirconias, while remained stable for ZTA composite and alumina. SIGNIFICANCE The synthesis of experimental 70-30% ZTA composite was successful and its relevance for dental applications relies on its higher masking ability, aging resistance, and strength similar to zirconia.
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Affiliation(s)
- Ernesto Byron Benalcazar Jalkh
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil; Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA.
| | - Kelli Nunes Monteiro
- Department of Biomaterials and Oral Biology, University of São Paulo, School of Dentistry, SP, Brazil
| | - Paulo Francisco Cesar
- Department of Biomaterials and Oral Biology, University of São Paulo, School of Dentistry, SP, Brazil
| | | | - Edmara T P Bergamo
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | | | - Erick Lima
- Department of Biomaterials and Oral Biology, University of São Paulo, School of Dentistry, SP, Brazil
| | | | | | - Lukasz Witek
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA; Department of Biomedical Engineering, New York University, Tandon School of Engineering, Brooklyn, NY, USA
| | - Paulo G Coelho
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA; Hansjörg Wyss Department of Plastic Surgery, NYU Langone Medical Center, New York, NY, USA; Mechanical and Aerospace Engineering, NYU Tandon School of Engineering, New York, NY, USA
| | - Ana Flavia Sanches Borges
- Department of Operative Dentistry, Endodontics and Dental Materials, University of São Paulo - Bauru School of Dentistry, Bauru, SP, Brazil
| | - Estevam A Bonfante
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
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Revilla-León M, Al-Haj Husain N, Ceballos L, Özcan M. Flexural strength and Weibull characteristics of stereolithography additive manufactured versus milled zirconia. J Prosthet Dent 2020; 125:685-690. [PMID: 32434662 DOI: 10.1016/j.prosdent.2020.01.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 01/21/2020] [Accepted: 01/21/2020] [Indexed: 11/25/2022]
Abstract
STATEMENT OF PROBLEM Zirconia restorations can be processed by using stereolithography additive manufacturing (AM) technologies. However, whether additive manufactured zirconia could achieve flexural strength values comparable with those of milled zirconia is unclear. PURPOSE The purpose of this in vitro study was to compare the flexural strength and Weibull characteristics of milled and additive manufactured zirconia. MATERIAL AND METHODS A total of 40 zirconia bars (25×4×1.2 mm) were obtained by using 2 manufacturing procedures, subtractive (CNC group) (IPS e.max ZirCAD; Ivoclar Vivadent AG) and additive manufacturing (AM group) (3DMix ZrO2; 3DCeram) technologies and assigned to 2 subgroups according to accelerating artificial aging procedures (mastication simulation): nonaged and aged (n=10). Flexural strength was measured in all specimens by using 3-point bend tests according to ISO/CD 6872.2 with a universal testing machine (Instron Model 8501; Instron Corp). Two-parameter Weibull distribution values, including the Weibull modulus, scale (m), and shape (0) were calculated. Flexural strength values were analyzed by using 2-way ANOVA and Student t statistical tests (α=.05). RESULTS The manufacturing procedure (P<.001), the mastication simulating aging procedure (P<.001), and the interaction between them (P<.001) significantly affected flexural strength values. The CNC group exhibited statistically higher flexural strength values than those in the AM group when the specimens were tested before performing an aging procedure (P<.001) and after mastication simulation (P<.001). Moreover, mastication simulation produced a significant reduction in flexural strength for both the CNC group (P<.039) and the AM group (P<.001). CONCLUSIONS The manufacturing process reported a significant effect on the flexural strength of the zirconia material tested. Mastication simulation as a means of accelerating artificial aging resulted in the significantly decreased flexural strength values of milled and additively manufactured zirconia material, with the Weibull moduli being significantly higher for the milled groups versus the milled specimens.
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Affiliation(s)
- Marta Revilla-León
- Assistant Professor and Assistant Program Director AEGD Residency, College of Dentistry, Texas A&M University, Dallas, Texas; Affiliate Faculty Graduate Prosthodontics University of Washington, Seattle, Wash; Researcher at Revilla Research Center, Madrid, Spain.
| | - Nadin Al-Haj Husain
- Specialization Candidate, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Laura Ceballos
- Associate Professor, Area of Stomatology, Rey Juan Carlos University, Madrid, Spain
| | - Mutlu Özcan
- Professor and Head, Dental Materials Unit, Center for Dental and Oral Medicine, University of Zürich, Zurich, Switzerland
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Lee B, Kwon JS, Khalid MW, Kim KM, Kim J, Lim KM, Hong SH. Boron nitride nanoplatelets as reinforcement material for dental ceramics. Dent Mater 2020; 36:744-754. [PMID: 32303354 DOI: 10.1016/j.dental.2020.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 03/10/2020] [Accepted: 03/12/2020] [Indexed: 10/24/2022]
Abstract
OBJECTIVE The main goal of this research was to demonstrate the potential value of boron nitride nanoplatelets (BNNPs), which have excellent mechanical properties and biocompatibility, as a suitable reinforcement for dental materials. METHODS The BNNPs were prepared by exfoliating h-BN via high-energy ball-milling and dispersion on a zirconia matrix. Then the composite powder was consolidated using spark plasma sintering. Fracture toughness, flexural strength and wear resistance were the mechanical properties explored. Agar diffusion-based biocompatibility testing was carried out. Low temperature degradation tests were also performed in a steam environment in an autoclave. RESULTS The BNNPs dispersed zirconia exhibited improved strength (up to 27.3%), and fracture toughness was also increased (up to 37.5%) with the addition of 1-1.5 vol.% BNNPs. Tribological properties were also enhanced by the addition of BNNPs. The cytotoxicity tests confirmed that the BNNPs do not have obvious toxicity. The accelerated low-temperature degradation experiment revealed the barrier properties of the BNNPs, whose addition almost fully inhibited the degradation of the zirconia matrix in a humid environment. SIGNIFICANCE The main contribution of this study is the introduction of an advanced material, BNNP, which can be used as a biocompatible reinforcement for dental materials, resulting in enhanced mechanical properties of the system due to its unique structure and extraordinary properties.
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Affiliation(s)
- Bin Lee
- Korea Institute for Rare Metal, Korea Institute of Industrial Technology, Yeonsu-gu, Incheon 21999, Republic of Korea.
| | - Jae-Sung Kwon
- Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Muhammad Waqas Khalid
- Korea Institute for Rare Metal, Korea Institute of Industrial Technology, Yeonsu-gu, Incheon 21999, Republic of Korea; Department of Industrial Materials and Smart Manufacturing Engineering, University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Kwang-Mahn Kim
- Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Joonhui Kim
- Center for R&D Performance Diffusion, Korea Institute of Science & Technology Evaluation and Planning (KISTEP), Eumseong-gun, Chungcheongbuk-do, 27740, Republic of Korea
| | - Kyoung Mook Lim
- Korea Institute for Rare Metal, Korea Institute of Industrial Technology, Yeonsu-gu, Incheon 21999, Republic of Korea
| | - Soon Hyung Hong
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon 34141, Republic of Korea.
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Aging resistance of an experimental zirconia-toughened alumina composite for large span dental prostheses: Optical and mechanical characterization. J Mech Behav Biomed Mater 2020; 104:103659. [DOI: 10.1016/j.jmbbm.2020.103659] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/21/2020] [Accepted: 01/27/2020] [Indexed: 02/04/2023]
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Yang H, Xu YL, Hong G, Yu H. Effects of low-temperature degradation on the surface roughness of yttria-stabilized tetragonal zirconia polycrystal ceramics: A systematic review and meta-analysis. J Prosthet Dent 2020; 125:222-230. [PMID: 32115216 DOI: 10.1016/j.prosdent.2020.01.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/16/2020] [Accepted: 01/16/2020] [Indexed: 11/15/2022]
Abstract
STATEMENT OF PROBLEM A wide range of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramics have been applied for dental restorations. However, whether hydrothermal aging affects the surface roughness of Y-TZP is unknown. PURPOSE The purpose of this systematic review and meta-analysis was to evaluate the effects of low-temperature degradation (LTD) on the surface roughness of Y-TZP ceramics. MATERIAL AND METHODS This report follows the Preferred Reporting Items for Systematic Reviews and Qualitative Analyses statement. The literature search was conducted with Medline through the PubMed, Web of Science, and Cochrane Library with no publication year limits. The screening and quality assessment were performed by 2 independent reviewers. The studies comparing the surface roughness of Y-TZP ceramics after LTD by using steam autoclave aging were included in the meta-analysis. Meta-analyses were conducted with a random-effects model (α=.05) by using Review Manager Software (Cochrane Collaboration). RESULTS Of the 203 potentially relevant studies, 32 full texts were assessed for eligibility. A total of 17 articles were included in the systematic review, and 15 were included in the qualitative analyses. The results showed no significant difference in the arithmetic average height (Ra) values between the nonaged and aged Y-TZP (P=.670; mean difference=0.01; 95% confidence interval=-0.03 to 0.05). Subgroup analyses revealed that the aging duration (P=.003) and specimen preparation (P=.010) contributed significantly to the changes in the surface roughness of the Y-TZP ceramics. CONCLUSIONS Although LTD was found to have no significant effects on the surface roughness of Y-TZP ceramics, the effects of LTD depended on the duration of the steam autoclave process and the specimen preparation.
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Affiliation(s)
- Hui Yang
- Postgraduate student, Fujian Key Laboratory of Oral Diseases & Fujian Provincial Engineering Research Center of Oral Biomaterial & Stomatological Key Laboratory of Fujian College and University, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, PR China
| | - Yi-Li Xu
- Postgraduate student, Fujian Key Laboratory of Oral Diseases & Fujian Provincial Engineering Research Center of Oral Biomaterial & Stomatological Key Laboratory of Fujian College and University, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, PR China
| | - Guang Hong
- Professor, Division for Globalization Initiative, Liaison Center for Innovative Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Hao Yu
- Associate Professor, Fujian Key Laboratory of Oral Diseases & Fujian Provincial Engineering Research Center of Oral Biomaterial & Stomatological Key Lab of Fujian College and University, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, PR China; Adjunct Associate Professor, Department of Applied Prosthodontics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
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da Rocha JFSS, de Avila ED, Rigolin MSM, Barbugli PA, Marin DOM, Mollo Junior FA, Jorge JH. Biological and physicochemical implications of the aging process on titanium and zirconia implant material surfaces. J Prosthet Dent 2020; 125:165-174. [PMID: 32037296 DOI: 10.1016/j.prosdent.2019.11.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 11/08/2019] [Accepted: 11/08/2019] [Indexed: 12/25/2022]
Abstract
STATEMENT OF PROBLEM Changes in physicochemical properties because of implant material aging and natural deterioration in the oral environment can facilitate microbial colonization and disturb the soft-tissue seal between the implant surfaces. PURPOSE The purpose of this in vitro study was to investigate the effect of aging time on the physicochemical profile of titanium (Ti) and zirconia (ZrO2) implant materials. Further microbiology and cell analyses were used to provide insights into the physicochemical implications of biological behavior. MATERIAL AND METHODS Disk-shaped specimens of Ti and ZrO2 were submitted to roughness, morphology, and surface free energy (SFE) analyses before nonaging (NA) and after the aging process (A). To simulate natural aging, disks were subjected to low-temperature degradation (LTD) by using an autoclave at 134 ºC and 0.2 MPa pressure for 20 hours. The biological activities of the Ti and ZrO2 surfaces were determined by analyzing Candida albicans (C. albicans) biofilms and human gingival fibroblast (HGF) cell proliferation. For the microbiology assays, a variance analysis method (ANOVA) was used with the Tukey post hoc test. For the evaluation of cellular proliferation, the Kruskal-Wallis test followed by Dunn multiple comparisons were used. RESULTS Ti nonaging (TNA) and ZrO2 nonaging (ZNA) disks displayed hydrophilic and lipophilic properties, and this effect was sustained after the aging process. Low-temperature degradation resulted in a modest change in intermolecular interaction, with 1.06-fold for TA and 1.10-fold for ZA. No difference in biofilm formation was observed between NA and A disks of the same material. After 48 hours, the viability of the attached HGF cells was very similar to that in the NA and A groups, regardless of the tested material. CONCLUSION The changes in the physicochemical properties of Ti and ZrO2 induced by the aging process do not interfere with C. albicans biofilm formation and HGF cell attachment, even after long-term exposure.
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Affiliation(s)
- José Francisco S S da Rocha
- Masters graduate, Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, São Paulo State University (UNESP), Araraquara, Brazil
| | - Erica D de Avila
- Postdoctoral Research Fellow, Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, São Paulo State University (UNESP), Araraquara, Brazil.
| | - Maria Sílvia M Rigolin
- Postdoctoral Research Fellow, Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, São Paulo State University (UNESP), Araraquara, Brazil
| | - Paula A Barbugli
- Technical Assistant, Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, São Paulo State University (UNESP), Araraquara, Brazil
| | - Danny O M Marin
- Assistant Professor, Department of Dentistry, Federal University of Santa Catarina (UFSC), Florianópolis, Brazil
| | - Francisco A Mollo Junior
- Associate Professor, Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, São Paulo State University (UNESP), Araraquara, Brazil
| | - Janaina H Jorge
- Associate Professor, Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, São Paulo State University (UNESP), Araraquara, Brazil
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Hatanaka GR, Polli GS, Adabo GL. The mechanical behavior of high-translucent monolithic zirconia after adjustment and finishing procedures and artificial aging. J Prosthet Dent 2020; 123:330-337. [DOI: 10.1016/j.prosdent.2018.12.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 12/16/2018] [Accepted: 12/17/2018] [Indexed: 11/29/2022]
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Effects of hydrothermal aging, thermal cycling, and water storage on the mechanical properties of a machinable resin-based composite containing nano-zirconia fillers. J Mech Behav Biomed Mater 2020; 102:103522. [DOI: 10.1016/j.jmbbm.2019.103522] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/01/2019] [Accepted: 11/04/2019] [Indexed: 02/04/2023]
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Prado PHCO, Monteiro JB, Campos TMB, Thim GP, de Melo RM. Degradation kinetics of high-translucency dental zirconias: Mechanical properties and in-depth analysis of phase transformation. J Mech Behav Biomed Mater 2020; 102:103482. [DOI: 10.1016/j.jmbbm.2019.103482] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/09/2019] [Accepted: 10/09/2019] [Indexed: 10/25/2022]
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Vila-Nova TEL, Gurgel de Carvalho IH, Moura DMD, Batista AUD, Zhang Y, Paskocimas CA, Bottino MA, de Assunção E Souza RO. Effect of finishing/polishing techniques and low temperature degradation on the surface topography, phase transformation and flexural strength of ultra-translucent ZrO 2 ceramic. Dent Mater 2020; 36:e126-e139. [PMID: 32008750 DOI: 10.1016/j.dental.2020.01.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 11/24/2019] [Accepted: 01/14/2020] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To investigate the effect of different surface finishing and polishing regimes and low temperature degradation on flexural strength, phase transformation and surface topography of ultra-translucent ZrO2 ceramic. METHODS 300 (n=15/group) of conventional zirconia (Z: Ice Zirkon Transluzent) and ultra-translucent zirconia (UT: Prettau Anterior) bar-specimens were made and divided according to the "Finishing/Polishing" - (C - Control, B - diamond rubber polishers, P - adjusting with burs, PB - adjusting with burs+diamond polishers, PG - adjusting with burs+glaze), "Low temperature Degradation (LTD)" (with or without a treatment at 127°C, 1.7bar/24h). Then, a 3-point mini flexural test was performed in a universal testing machine (1mm/min, 500kgf load cell). SEM, EDS, XDR, AFM, optical profilometry and Weibull analysis were performed. Data were analyzed by 3-way ANOVA and Tukey's post-test (5%). RESULTS Groups ZPBD (1670±253MPa), ZBD (1664±217MPa), and ZB (1655±3678MPa) showed significantly higher flexural strength than the UTPG group (372±56MPa). The Weibull modulus was significantly higher for the ZPD group compared to the UB, UCD, UPD and UPBD, while UTB, UTCD and UTPD had the lowest value. Monoclinic phases were observed only in the conventional zirconia groups and were more evident after LTD. Diamond rubber polishers presented less roughness for both zirconias. SIGNIFICANCE The use of diamond rubber polishers is the most suitable finishing/polishing method for zirconia ceramic restorations and that final glazing reduces the fracture resistance of these materials.
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Affiliation(s)
- Taciana Emília Leite Vila-Nova
- Federal University of Rio Grande do Norte (UFRN), Department of Dentistry, Av. Salgado Filho, 1787, Lagoa Nova, Natal, RN, CEP: 59056-000, Brazil.
| | - Isabelle Helena Gurgel de Carvalho
- Federal University of Rio Grande do Norte (UFRN), Department of Dentistry, Division of Prosthodontics, Av. Salgado Filho, 1787, Lagoa Nova, Natal, RN, 59056-000, Brazil.
| | - Dayanne Monielle Duarte Moura
- Federal University of Rio Grande do Norte (UFRN), Department of Dentistry, Division of Prosthodontics, Av. Salgado Filho, 1787, Lagoa Nova, Natal, RN, 59056-000, Brazil.
| | - André Ulisses Dantas Batista
- Federal University of Paraíba (UFPB), Department of Restorative Dentistry, Conj. Pres. Castelo Branco III, João Pessoa, PB, 58033-455, Brazil.
| | - Yu Zhang
- New York University College of Dentistry, Department of Biomaterials and Biomimetics, 433 First Avenue, Room 810, New York, NY, 10010, United States.
| | - Carlos Alberto Paskocimas
- Federal University of Rio Grande do Norte (UFRN), Department of Material Engineering, Av. Salgado Filho, 3000, Lagoa Nova, Natal, RN, Brazil.
| | - Marco Antonio Bottino
- São Paulo State University (UNESP), Institute of Science and Technology, Av Engenheiro Francisco José Longo, 777, Jardim São Dimas, São José dos Campos, São Paulo, São José dos Campos, CEP: 12245-000, Brazil.
| | - Rodrigo Othávio de Assunção E Souza
- Adjunct Professor at Federal University of Rio Grande do Norte (UFRN), Department of Dentistry, Division of Prosthodontics, Av. Salgado Filho, 1787, Lagoa Nova, Natal, RN, 59056-000, Brazil.
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Wang L, Wang C, Wu S, Fan Y, Li X. Influence of the mechanical properties of biomaterials on degradability, cell behaviors and signaling pathways: current progress and challenges. Biomater Sci 2020; 8:2714-2733. [DOI: 10.1039/d0bm00269k] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have clarified the influence of the mechanical properties of biomaterials on degradability and cell response, and also mechanical design targets and approaches.
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Affiliation(s)
- Lu Wang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education
- School of Biological Science and Medical Engineering
- Beihang University
- Beijing 100083
- China
| | - Cunyang Wang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education
- School of Biological Science and Medical Engineering
- Beihang University
- Beijing 100083
- China
| | - Shuai Wu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education
- School of Biological Science and Medical Engineering
- Beihang University
- Beijing 100083
- China
| | - Yubo Fan
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education
- School of Biological Science and Medical Engineering
- Beihang University
- Beijing 100083
- China
| | - Xiaoming Li
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education
- School of Biological Science and Medical Engineering
- Beihang University
- Beijing 100083
- China
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Moqbel NM, Al-Akhali M, Wille S, Kern M. Influence of Aging on Biaxial Flexural Strength and Hardness of Translucent 3Y-TZP. MATERIALS 2019; 13:ma13010027. [PMID: 31861613 PMCID: PMC6981501 DOI: 10.3390/ma13010027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/02/2019] [Accepted: 12/13/2019] [Indexed: 11/16/2022]
Abstract
The purpose of this research was to evaluate the influence of aging and surface treatment on surface roughness, biaxial flexural strength (BFS), and Vickers hardness (VHN) of translucent dental zirconia. Half of 80 disc-shaped zirconia specimens (1.2 mm thickness and 12 mm diameter) were aged (group A) in an autoclave for 20 h (134 °C and 0.2 MPa) and the other half were not aged (group N). Specimens were subjected to: no surface treatment (SIN), particle air-abrasion with 50 µm alumina particles at 1 bar (0.1 MPa) and 2.5 bar (0.25 MPa), or polishing down to 1 µm (POL). Specimens were analyzed using X-ray diffraction, laser scanning microscope, BFS, and VHN tests. Three groups (N-SIN, N-POL, and A-POL) showed almost no monoclinic phase. While other groups showed monoclinic phase ratios ranging from 7.5 vol. % ± 2.4 vol. % (N-0.1 MPa) to 41.5 vol. % ± 0.3 vol. % (A-0.1 MPa). Aging and particle air-abrasion increased significantly the BFS, ranging from 720 ± 37 MPa (N-SIN) to 1153 ± 92 MPa (N-0.1 MPa). The hardness was not influenced significantly by aging. A certain amount of monoclinic phase at the surface strengthens the high translucent dental zirconia, while hardness and roughness are not influenced. The pressure of particle air-abrasion showed no influence on the evaluated properties.
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Affiliation(s)
- Nawal M. Moqbel
- Correspondence: ; Tel.: +49-0431-500-264-10; Fax: +49-0431-500-264-04
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Bonfante EA, Jimbo R, Witek L, Tovar N, Neiva R, Torroni A, Coelho PG. Biomaterial and biomechanical considerations to prevent risks in implant therapy. Periodontol 2000 2019; 81:139-151. [PMID: 31407440 DOI: 10.1111/prd.12288] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This paper is aimed to present a biomaterials perspective in implant therapy that fosters improved bone response and long-term biomechanical competence from surgical instrumentation to final prosthetic rehabilitation. Strategies to develop implant surface texturing will be presented and their role as an ad hoc treatment discussed in light of the interplay between surgical instrumentation and implant macrogeometric configuration. Evidence from human retrieved implants in service for several years and from in vivo studies will be used to show how the interplay between surgical instrumentation and implant macrogeometry design affect osseointegration healing pathways, and bone morphologic and long-term mechanical properties. Also, the planning of implant-supported prosthetic rehabilitations targeted at long-term performance will be appraised from a standpoint where personal preferences (eg, cementing or screwing a prosthesis) can very often fail to deliver the best patient care. Lastly, the acknowledgement that every rehabilitation will have its strength degraded over time once in function will be highlighted, since the potential occurrence of even minor failures is rarely presented to patients prior to treatment.
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Affiliation(s)
- Estevam A Bonfante
- Department of Prosthodontics and Periodontology, University of São Paulo Bauru School of Dentistry, Bauru, Brazil
| | - Ryo Jimbo
- Department of Applied Prosthodontics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Lukasz Witek
- Department of Biomaterials, New York University, New York City, New York, USA
| | - Nick Tovar
- Department of Biomaterials, New York University, New York City, New York, USA
| | - Rodrigo Neiva
- Department of Periodontology, University of Florida at Gainesville, Gainesville, Florida, USA
| | - Andrea Torroni
- Attending Oral and Maxillofacial Surgery, Hansjörg Wyss Department of Plastic Surgery, New York University Langone Medical Center, New York City, New York, USA
| | - Paulo G Coelho
- Department of Biomaterials, Hansjörg Wyss Department of Plastic Surgery, Mechanical and Aerospace Engineering, New York University, New York City, New York, USA
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Cadore-Rodrigues AC, Prochnow C, Rippe MP, Oliveira JSD, Jahn SL, Foletto EL, Pereira GKR, Valandro LF. Air-abrasion using new silica-alumina powders containing different silica concentrations: Effect on the microstructural characteristics and fatigue behavior of a Y-TZP ceramic. J Mech Behav Biomed Mater 2019; 98:11-19. [DOI: 10.1016/j.jmbbm.2019.05.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/20/2019] [Accepted: 05/21/2019] [Indexed: 12/20/2022]
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Elshafay A, Omran ES, Abdelkhalek M, El-Badry MO, Eisa HG, Fala SY, Dang T, Ghanem MAT, Elbadawy M, Elhady MT, Vuong NL, Hirayama K, Huy NT. Reporting quality in systematic reviews of in vitro studies: a systematic review. Curr Med Res Opin 2019; 35:1631-1641. [PMID: 30977685 DOI: 10.1080/03007995.2019.1607270] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Background: Systematic reviews (SRs) and/or meta-analyses of in vitro research have an important role in establishing the foundation for clinical studies. In this study, we aimed to evaluate the reporting quality of SRs of in vitro studies using the PRISMA checklist.Method: Four databases were searched including PubMed, Virtual Health Library (VHL), Web of Science (ISI) and Scopus. The search was limited from 2006 to 2016 to include all SRs and/or meta-analyses (MAs) of pure in vitro studies. The evaluation of reporting quality was done using the PRISMA checklist.Results: Out of 7702 search results, 65 SRs were included and evaluated with the PRISMA checklist. Overall, the mean overall quality score of reported items of the PRISMA checklist was 68%. We have noticed an increasing pattern in the numbers of published SRs of in vitro studies over the last 10 years. In contrast, the reporting quality was not significantly improved over the same period (p = .363). There was a positive but not significant correlation between the overall quality score and the journal impact factor of the included studies.Conclusions: The adherence of SRs of in vitro studies to the PRISMA guidelines was poor. Therefore, we believe that using reporting guidelines and journals paying attention to this fact will improve the quality of SRs of in vitro studies.
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Affiliation(s)
- Abdelrahman Elshafay
- Faculty of Medicine, Al-Azhar University, Cairo, Egypt
- Online Research Club (http://www.onlineresearchclub.org/)
| | - Esraa Salah Omran
- Online Research Club (http://www.onlineresearchclub.org/)
- Kasralainy School of Medicine, Cairo University, Cairo, Egypt
| | - Mariam Abdelkhalek
- Online Research Club (http://www.onlineresearchclub.org/)
- Microbiology and Immunology Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Mohamed Omar El-Badry
- Faculty of Medicine, Al-Azhar University, Cairo, Egypt
- Online Research Club (http://www.onlineresearchclub.org/)
| | - Heba Gamal Eisa
- Online Research Club (http://www.onlineresearchclub.org/)
- Faculty of Medicine, Menoufia University, Shebin El-Kom, Egypt
| | - Salma Y Fala
- Online Research Club (http://www.onlineresearchclub.org/)
- Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Thao Dang
- Online Research Club (http://www.onlineresearchclub.org/)
- Surgery Department School of Medicine, Tan Tao University, Tan Duc Ecity, Vietnam
| | - Mohammad A T Ghanem
- Online Research Club (http://www.onlineresearchclub.org/)
- Department of Vascular Surgery, Uniklinik Magdeburg, Magdeburg, Germany
| | - Maha Elbadawy
- Online Research Club (http://www.onlineresearchclub.org/)
- Ministry of Health, Cairo, Egypt
| | - Mohamed Tamer Elhady
- Online Research Club (http://www.onlineresearchclub.org/)
- Department of Pediatrics, Zagazig University Hospitals, Faculty of Medicine, Sharkia, Egypt
| | - Nguyen Lam Vuong
- Online Research Club (http://www.onlineresearchclub.org/)
- Department of Medical Statistics and Informatics, Faculty of Public Health, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Kenji Hirayama
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Nguyen Tien Huy
- Evidence Based Medicine Research Group & Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam
- Department of Clinical Product Development, Institute of Tropical Medicine (NEKKEN), School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
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Kelch M, Schulz J, Edelhoff D, Sener B, Stawarczyk B. Impact of different pretreatments and aging procedures on the flexural strength and phase structure of zirconia ceramics. Dent Mater 2019; 35:1439-1449. [PMID: 31399228 DOI: 10.1016/j.dental.2019.07.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 06/14/2019] [Accepted: 07/15/2019] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To test the impact of zirconia pretreatment and aging on flexural strength and phase structure. METHODS For flexural strength measurements, 180 3Y-TZP0.25 specimens were fabricated and pretreated: (i) air-abraded (105-μm alumina, 0.25MPa), (ii) air-abraded (50-μm alumina, 0.25MPa), (iii) air-abraded (30-μm silica-coated alumina, 0.28MPa) (iv) non-pretreated. Each pretreated group (n=15) was aged: (a) hydrothermal (134°C, 0.23MPa, 2h) (b) in a mastication simulator (1,200,000×, 5/55°C) and (c) not aged. The fractured specimens were stored dry for 5 years (23°C) for analysis of phase transformation. Additionally, specimens were fabricated from 3Y-TZP0.25 (n=12) and 3Y-TZP0.05 (n=8), pretreated (i, ii, iii, iv), and hydrothermally aged. Each air-abrasion method was alternated using 0.05, 0.25 and 0.4MPa pressure. The phase transformation was examined by Raman spectroscopy and surface topography by scanning electron microscope. Data were analyzed using univariate ANOVA with the Scheffé post hoc test and partial-eta-squared (ƞp²) (α=0.05). RESULTS The highest impact on flexural strength was exerted by the pretreatment (ηP²=0.261, p<0.001), followed by interactions between pretreatment and aging (ηP²=0.077, p=0.033). Non-pretreated and non-aged specimens showed the lowest monoclinic percentage. Hydrothermal aging and 5 years of storage at room temperature increased the monolithic percentage of 3Y-TZP0.25. The highest phase transformation was observed in groups air-abraded with 105-μm alumina particles. Increasing pressure during the air-abrading process increased the content of the monoclinic phase in zirconia surfaces. SIGNIFICANCE Air-abrasion with 30-μm silica-coated alumina powder can be recommended for pretreatment of 3Y-TZP0.25 and 3Y-TZP0.05. For air-abrasion using alumina powder lower pressure should be used.
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Affiliation(s)
- Matthias Kelch
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany.
| | - Julian Schulz
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Daniel Edelhoff
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Beatrice Sener
- Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zurich, Plattenstrasse 11, 8032 Zurich, Switzerland
| | - Bogna Stawarczyk
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
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Schepke U, Gresnigt MMM, Browne WR, Abdolahzadeh S, Nijkamp J, Cune MS. Phase transformation and fracture load of stock and CAD/CAM‐customized zirconia abutments after 1 year of clinical function. Clin Oral Implants Res 2019; 30:559-569. [DOI: 10.1111/clr.13442] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 03/17/2019] [Accepted: 03/29/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Ulf Schepke
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene University Medical Center Groningen, University of Groningen Groningen The Netherlands
| | - Marco M. M. Gresnigt
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene University Medical Center Groningen, University of Groningen Groningen The Netherlands
| | - Wesley R. Browne
- Faculty of Mathematics and Natural Sciences, Molecular Inorganic Chemistry, Stratingh Institute for Chemistry University of Groningen Groningen The Netherlands
| | - Shaghayegh Abdolahzadeh
- Faculty of Mathematics and Natural Sciences, Molecular Inorganic Chemistry, Stratingh Institute for Chemistry University of Groningen Groningen The Netherlands
| | - Joey Nijkamp
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene University Medical Center Groningen, University of Groningen Groningen The Netherlands
| | - Marco S. Cune
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene University Medical Center Groningen, University of Groningen Groningen The Netherlands
- Department of Oral and Maxillofacial Surgery, Prosthodontics and Special Dental Care St. Antonius Hospital Nieuwegein The Netherlands
- Department of Oral and Maxillofacial Surgery, Prosthodontics and Special Dental Care University Medical Center Utrecht Utrecht The Netherlands
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77
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Sundh A, Kou W, Sjögren G. Effects of Pretreatment, Specimen Thickness, and Artificial Aging on Biaxial Flexural Strength of Two Types of Y-TZP Ceramics. Oper Dent 2019; 44:615-624. [PMID: 30978157 DOI: 10.2341/18-071-l] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES To evaluate the effects of surface treatment, specimen thickness, and aging on the biaxial flexural strength (BFS) of two types of yttria-stabilized, tetragonal zirconia polycrystal (Y-TZP) ceramics. METHODS AND MATERIALS Disc-shaped specimens, 0.4 and 1.3 mm thick, made from hot isostatic pressed (Denzir) and non-hot isostatic pressed (ZirPlus) Y-TZP, were sandblasted, heat treated, and autoclaved. The surface topography was assessed in accordance with European Standard 623-624:2004 and the BFS tests in accordance with International Organization for Standardization Standard 6872:2008. For statistical analyses, one-way Shapiro-Wilk test, analysis of variance (post hoc: least significant differences), Mann-Whitney U-test, and Pearson correlation tests (p<0.05) were used. RESULTS As delivered, the BFS of the 0.4-mm ZirPlus was >1.3-mm ZirPlus (p<0.01), and the BFS of the 0.4-mm Denzir was >1.3-mm Denzir (p<0.001). Sandblasting with 0.2 MPa reduced the BFS of the ZirPlus and Denzir discs (p<0.01), whereas sandblasting with 0.6 MPa increased the BFS of the 0.4-mm Denzir (p<0.001) and reduced the BFS of the 0.4-mm ZirPlus (p<0.05). Heat treatment significantly reduced the BFS of all the groups except for the 0.6 MPa sandblasted 0.4-mm ZirPlus. Autoclaving reduced the BFS of the as-delivered ZirPlus and Denzir specimens (p<0.001), whereas autoclaving the 0.6 MPa sandblasted and heat-treated specimens had no effect (p>0.05) on the BFS. The 0.6 MPa sandblasted, heat-treated, and autoclaved 0.4-mm Denzir exhibited higher BFS than the 0.6 MPa sandblasted, heat-treated, and autoclaved 0.4-mm ZirPlus (p<0.05). CONCLUSIONS Thickness and surface treatment of Y-TZP-based ceramics should be considered since those factors could influence the BFS of the material.
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Sorrentino R, Navarra CO, Di Lenarda R, Breschi L, Zarone F, Cadenaro M, Spagnuolo G. Effects of Finish Line Design and Fatigue Cyclic Loading on Phase Transformation of Zirconia Dental Ceramics: A Qualitative Micro-Raman Spectroscopic Analysis. MATERIALS 2019; 12:ma12060863. [PMID: 30875849 PMCID: PMC6470560 DOI: 10.3390/ma12060863] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 02/28/2019] [Accepted: 03/12/2019] [Indexed: 11/16/2022]
Abstract
Objectives: Stresses produced during the fabrication of copings and by chewing activity can induce a tetragonal-to-monoclinic (t–m) transformation of zirconia. As a consequence, in the m-phase, the material is not able to hinder possible cracks by the favorable mechanism known as “transformation toughening”. This study aimed at evaluating if different marginal preparations of zirconia copings can cause a premature phase transformation immediately after manufacturing milling and after chewing simulation. Methods: Ninety copings using three commercial zirconia ceramics (Nobel Procera Zirconia, Nobel Biocare Management AG; Lava Classic, 3M ESPE; Lava Plus, 3M ESPE) were prepared with deep-chamfer, slight-chamfer, or feather-edge finish lines (n = 10). Specimens were tested in a chewing simulator (CS-4.4, SD Mechatronik) under cyclic occlusal loads simulating one year of clinical service. Raman spectra were acquired and analyzed for each specimen along the finish lines and at the top of each coping before and after chewing simulation, respectively. Results: Raman analysis did not show any t–m transformation both before and after chewing simulation, as the typical monoclinic bands at 181 cm−1 and 192 cm−1 were not detected in any of the tested specimens. Conclusions: After a one-year simulation of chewing activity, irrespective of preparation geometry, zirconia copings did not show any sign of t–m transformation, either in the load application areas or at the margins. Consequently, manufacturing milling even in thin thickness did not cause any structural modification of zirconia ceramics “as received by manufacturers” both before and after chewing simulation.
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Affiliation(s)
- Roberto Sorrentino
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Prosthodontics and Digital Dentistry, University of Naples "Federico II", via S. Pansini 5, 80131 Naples, Italy.
| | - Chiara Ottavia Navarra
- Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, 34129 Trieste, Italy.
| | - Roberto Di Lenarda
- Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, 34129 Trieste, Italy.
| | - Lorenzo Breschi
- Department of Biomedical Science and Neuromotor Sciences, DIBINEM, University of Bologna, Via San Vitale 59, 40123 Bologna, Italy.
| | - Fernando Zarone
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Prosthodontics and Digital Dentistry, University of Naples "Federico II", via S. Pansini 5, 80131 Naples, Italy.
| | - Milena Cadenaro
- Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, 34129 Trieste, Italy.
| | - Gianrico Spagnuolo
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Prosthodontics and Digital Dentistry, University of Naples "Federico II", via S. Pansini 5, 80131 Naples, Italy.
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Volpato CAM, Carvalho ÓSN, Pereira MRDC, Correia Pereira da Silva FS. Evaluation of the color and translucency of glass-infiltrated zirconia based on the concept of functionally graded materials. J Prosthet Dent 2019; 121:547.e1-547.e7. [PMID: 30661878 DOI: 10.1016/j.prosdent.2018.09.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 09/20/2018] [Accepted: 09/20/2018] [Indexed: 11/26/2022]
Abstract
STATEMENT OF PROBLEM Infiltrated zirconia has promising mechanical properties. However, information about its optical behavior is scarce. PURPOSE The purpose of this in vitro study was to evaluate the color and translucency of zirconia submitted to infiltration and aging. MATERIAL AND METHODS Sixty zirconia disks were machined. Ten disks received no treatment (NT group), 10 disks were immersed in a coloring liquid (A2 group), and 10 disks were immersed in a fluorescent liquid (F group). The other 30 disks were submitted to the same treatments plus glass infiltration (NT+I, A2+I, and F+I groups). The coordinates L*, a*, and b* and the Y tristimulus values were obtained to calculate the color (ΔE00), lightness, chroma, and hue differences; the translucency parameter (TP); and the contrast ratio (CR) associated with the specimens. After aging in an autoclave for 4 hours (T1), new measurements were made. Two- and 3-way ANOVAs were used to analyze color differences, TP, and CR. The lightness, chroma, and hue differences were evaluated by a repeated measures ANOVA. Multiple comparisons were made with the Tukey honestly significant difference (HSD) test (α=.05). RESULTS The greatest color differences were observed in the A2+I group (11.23 ΔE00) (P<.001). Aging affected the chroma of the colored groups (P=.013 and P=.001) but did not affect their translucency (P=.347 for TP and P=.132 for CR). The greatest TP values were found in the NT and NT+I groups (2.54 and 2.34, respectively), whereas the CR was equal to or close to 1 in all groups. CONCLUSIONS Color differences were observed in the glass-infiltrated groups. The TP and CR were affected by infiltration. Aging did not influence the optical behavior of the specimens.
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Affiliation(s)
| | - Óscar Samuel Novais Carvalho
- Assistant Professor, Department of Mechanical Engineering, University of Minho (UMinho), Azurém Campus, Guimarães, Portugal
| | - Mário Rui da Cunha Pereira
- Assistant Professor, Department of Physics, University of Minho (UMinho), Gualtar Campus, Braga, Portugal
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Effect of hydrothermal aging on the optical properties of precolored dental monolithic zirconia ceramics. J Prosthet Dent 2018; 121:676-682. [PMID: 30580981 DOI: 10.1016/j.prosdent.2018.06.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 06/27/2018] [Accepted: 06/27/2018] [Indexed: 11/20/2022]
Abstract
STATEMENT OF PROBLEM The long-term color stability of precolored monolithic zirconia has not been thoroughly investigated. PURPOSE The purpose of this in vitro study was to evaluate the effect of hydrothermal aging on the optical properties, phase transformation, and surface topography of precolored monolithic zirconia ceramics. MATERIAL AND METHODS Precolored monolithic zirconia specimens (17.0×17.0×1.5 mm, n=50) and lithium disilicate glass-ceramic specimens (16.0×16.0×1.5 mm, n=50) were artificially aged in an autoclave at 134°C under 0.2 MPa for 0, 1, 3, 5, or 10 hours (n=10). CIELab color parameters were obtained from spectral measurements. The translucency parameter (TP) and CIEDE2000 color differences (ΔE00) were calculated. The microstructural and surface properties were analyzed by X-ray diffraction (XRD), atomic force microscope (AFM), and scanning electron microscope (SEM). Data were analyzed with 2-way ANOVA and pairwise comparison (α=.05). RESULTS Significant interactions were found between aging time and ceramic material on L*, a*, b*, and TP (P<.001) as follows: b* partial eta squared [ηp2]=0.689; L* ηp2=0.186; a* ηp2=0.176; and TP ηp2=0.137. The b* values significantly decreased after aging for zirconia (P<.001), whereas TP increased after aging for zirconia (P<.014) except at 10 hours (P=.389) and for lithium disilicate (P<.001). The ΔE00 values relative to baseline ranged from 2.03 to 2.52 for aged zirconia and from 0.07 to 0.23 for aged lithium disilicate. XRD analysis revealed that hydrothermal aging promoted an increase in m-phase contents. AFM and SEM demonstrated surface alterations after aging. CONCLUSIONS Optical properties and microstructures of precolored monolithic zirconia ceramics were affected by hydrothermal aging, and translucency increased slightly with aging time.
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81
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Dal Piva AM, Tribst JP, Gondim LD, Ribeiro IL, Campos F, Arata A, Souza RO. Y-TZP surface behavior under two different milling systems and three different accelerated aging protocols. ACTA ACUST UNITED AC 2018; 67:237-245. [PMID: 30499286 DOI: 10.23736/s0026-4970.18.04138-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND To evaluate the influence of aging and milling system on zirconia surface roughness (SR) and phase transformation. METHODS Eighty crowns were divided in two groups according to yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) ceramic milling system (CAD-Neodent or MAD-Zirkonzahn). The crowns were submitted to different aging protocols (N.=10): 1) no aging; 2) autoclaving; 3) pH cycling; or 4) thermocycling. Next, the samples were submitted to an optical profilometry analysis to determine differences in the SR (µm). An X-ray diffraction analysis (XRD) was performed to quantify the percentage of monoclinic phase transformation. SR data was analyzed by two-way ANOVA (α=0.5%). RESULTS Aging protocol (P=0.42) and milling system (P=0.08) had no influence on the SR. However, the number of monoclinic phases was influenced by the autoclaving and pH cycling. CONCLUSIONS The surface roughness of zirconia-based crowns was not influenced by low temperature degradation or milling system. Regarding the phase transformation, autoclaving and pH-cycling aging presented a monoclinic phase increase when compared to the control group and thermocycled groups.
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Affiliation(s)
- Amanda M Dal Piva
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), São José dos Campos, Brazil -
| | - João Paulo Tribst
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), São José dos Campos, Brazil
| | - Laísa D Gondim
- Federal University of Paraíba (UFPB), João Pessoa, Brazil
| | - Isabella L Ribeiro
- Department of Social Odontology, Federal University of Paraíba (UFPB), João Pessoa, Brazil
| | - Fernanda Campos
- Department of Dentistry, Paraíba State University (UEPB), Araruna, Brazil
| | - Anelyse Arata
- Nuclear and Energy Research Institute, National Nuclear Energy Commission (IPEN-CNEN/SP), São Paulo, Brazil
| | - Rodrigo O Souza
- Division of Prosthodontics, Department of Restorative Dentistry, Federal University of Federal University of Rio Grande do Norte (UFRN), Natal, Brazil
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82
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Gou M, Chen H, Kang J, Wang H. Antagonist enamel wear of tooth-supported monolithic zirconia posterior crowns in vivo: A systematic review. J Prosthet Dent 2018; 121:598-603. [PMID: 30509545 DOI: 10.1016/j.prosdent.2018.06.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 06/13/2018] [Accepted: 06/14/2018] [Indexed: 02/05/2023]
Abstract
STATEMENT OF PROBLEM An assessment of the evidence for the antagonist enamel wear of tooth-supported monolithic zirconia posterior crowns is lacking. PURPOSE The purpose of this systematic review was to identify and summarize clinical studies related to the antagonist enamel wear of tooth-supported monolithic zirconia posterior crowns. MATERIAL AND METHODS PubMed, Embase, and Cochrane library searches were performed and complemented by manual searches from database inception to December 25, 2017, for title and abstract analysis. RESULTS Initially, 198 articles were obtained through database searches. Twenty-one articles were selected for full-text analysis, and 5 studies met the inclusion criteria. Because of the heterogeneity in design, surface treatment, measurement methods, and wear parameters, a meta-analysis was not possible. The selected studies were analyzed regarding the antagonist natural enamel wear of zirconia, measurement methods, and surface treatment. The results of the antagonist enamel wear varied widely, which made comparing them scientifically with absolute values difficult. CONCLUSIONS This review indicated that the antagonist enamel wear of zirconia was similar to or more than that of natural teeth but less than that of metal-ceramics. Additional properly designed, longer follow-up clinical trials with larger sample sizes are needed to evaluate the antagonist enamel wear of monolithic zirconia crowns in vivo.
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Affiliation(s)
- Min Gou
- Doctoral student, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, PR China
| | - Helin Chen
- Doctoral student, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, PR China
| | - Jian Kang
- Doctoral student, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, PR China
| | - Hang Wang
- Professor, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, PR China.
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83
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Mechanical performance of Y-TZP monolithic ceramic after grinding and aging: Survival estimates and fatigue strength. J Mech Behav Biomed Mater 2018; 87:288-295. [DOI: 10.1016/j.jmbbm.2018.07.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 07/25/2018] [Accepted: 07/29/2018] [Indexed: 12/21/2022]
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84
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Hao Z, Ma Y, Liu W, Meng Y, Nakamura K, Shen J, Wang H. Influence of low-temperature degradation on the wear characteristics of zirconia against polymer-infiltrated ceramic-network material. J Prosthet Dent 2018; 120:596-602. [DOI: 10.1016/j.prosdent.2017.12.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 12/14/2017] [Accepted: 12/14/2017] [Indexed: 10/17/2022]
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Current status of zirconia implants in dentistry: preclinical tests. J Prosthodont Res 2018; 63:1-14. [PMID: 30205949 DOI: 10.1016/j.jpor.2018.07.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 07/18/2018] [Accepted: 07/26/2018] [Indexed: 11/23/2022]
Abstract
PURPOSE This systematic review aimed to provide an overview of zirconia implants as well as regarding the outcome of the implant-restorative complex in preclinical studies. STUDY SELECTION An electronic search of the literature prior to July 2017 was performed to identify all articles related to preclinical research on zirconia implants. The search was conducted using MEDLINE (National Library of Medicine) and PubMed without restrictions concerning the date of publication. The search terminology included: zirconia implant, osseointegration, bone-to-implant contact, soft tissue, histology, histomorphometry, surface modification, surface roughness, surface characteristics, and restoration (connecting multiple keywords with AND, OR). RESULTS Fifty-seven studies were finally selected from an initial yield of 654 titles, and the data were extracted. The identified preclinical studies focused on several aspects related to zirconia implants, namely biocompatibility, mechanical properties, implant design, osseointegration capacity, soft tissue response, and restorative options. Due to heterogeneity of the studies, a meta-analysis was not possible. The most frequently used zirconia material for the fabrication of implants is yttria-stabilized tetragonal zirconia polycrystal. The resistance-to-fracture for zirconia implants ranged between 516-2044N. The mostly investigated parameter was osseointegration, which is compared to that of titanium. A lack of evidence was found with other parameters. CONCLUSIONS Due to its good biocompatibility as well as favorable physical and mechanical properties, zirconia implants are a potential alternative to titanium implants. However, knowledge regarding the implant-restorative complex and related aspects is still immature to recommend its application for daily practice.
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86
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Pereira GKR, Guilardi LF, Dapieve KS, Kleverlaan CJ, Rippe MP, Valandro LF. Mechanical reliability, fatigue strength and survival analysis of new polycrystalline translucent zirconia ceramics for monolithic restorations. J Mech Behav Biomed Mater 2018; 85:57-65. [PMID: 29857261 DOI: 10.1016/j.jmbbm.2018.05.029] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/16/2018] [Accepted: 05/21/2018] [Indexed: 11/16/2022]
Abstract
This study characterized the mechanical properties (static and under fatigue), the crystalline microstructure (monoclinic - m, tetragonal - t and cubic - c phase contents) and the surface topography of three yttrium-stabilized zirconia (YSZ) materials with different translucent properties, before and after aging in an autoclave (low temperature degradation). Disc-shaped specimens were produced from second generation (Katana ML/HT - high-translucent) and third generations (Katana STML - super-translucent and UTML - ultra-translucent) YSZ ceramics (Kuraray Noritake Dental Inc.), following ISO 6872-2015 guidelines for biaxial flexural strength testing (final dimensions: 15 mm in diameter and 1.2 ± 0.2 mm in thickness), and then subjected to the respective tests and analyses. ML was mainly composed of tetragonal crystals, while STML and UTML presented cubic content. Aging increased the monoclinic content for ML and did not affect STML and UTML. Topographical analysis highlights different grain sizes on the ceramic surface (UTML > STML > ML) and aging had no effect on this outcome. Weibull analysis showed the highest characteristic strength for ML both before and after aging, and statistically similar Weibull moduli for all groups. ML material also obtained the highest survival rates (ML > STML > UTML) for both fatigue strength and number of cycles to failure. All fractures originated from surface defects on the tensile side. Third generation zirconia (Katana STML and UTML) are fully stabilized materials (with tetragonal and cubic crystals), being totally inert to the autoclave aging, and presented lower mechanical properties than the second-generation zirconia (Katana ML - metastable zirconia).
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Affiliation(s)
- Gabriel K R Pereira
- MSciD Graduate Program, School of Dentistry, Meridional Faculty - IMED, Passo Fundo, Rio Grande do Sul, Brazil; PhD-MSciD Graduate Program in Oral Science (Prosthodontics Unit), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
| | - Luís F Guilardi
- PhD-MSciD Graduate Program in Oral Science (Prosthodontics Unit), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil; Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands.
| | - Kiara S Dapieve
- PhD-MSciD Graduate Program in Oral Science (Prosthodontics Unit), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
| | - Cornelis J Kleverlaan
- Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands.
| | - Marília P Rippe
- PhD-MSciD Graduate Program in Oral Science (Prosthodontics Unit), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
| | - Luiz Felipe Valandro
- PhD-MSciD Graduate Program in Oral Science (Prosthodontics Unit), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
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Candido LM, Miotto LN, Fais LMG, Cesar PF, Pinelli LAP. Mechanical and Surface Properties of Monolithic Zirconia. Oper Dent 2018; 43:E119-E128. [DOI: 10.2341/17-019-l] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
Purpose:
This study compared monolithic zirconia with conventional ones based on mean roughness (Ra), Vickers hardness (VHN), topography, transmittance, grain size, flexural strength (FS), Weibull modulus, and fractographic behavior.
Methods and Materials:
One monolithic (Prettau Zircon [PR group]) and two conventional (ICE Zirkon Transluzent [IZ group] and BloomZir [BL group]) zirconias were used. Specimens were tested using a profilometer, a microhardness tester, a scanning electron microscope, a spectrophotometer, and a Universal Testing Machine (EMIC DL 2000). Ra, VHN, grain size, and transmittance were analyzed using the Kruskal-Wallis test associated with Dunn test (α=0.05). FS was analyzed using one-way analysis of variance with the Tukey honestly significant difference test (α=0.05).
Results:
Means and standard deviations of roughness, after sintering (Ra, in μm) and VHN, were, respectively, 0.11 ± 0.01, 1452.16 ± 79.49, for the PR group; 0.12 ± 0.02, 1466.72 ± 91.76, for the IZ group; and 0.21 ± 0.08, 1516.06 ± 104.02, for the BL group. BL was statistically rougher (p<0.01) than PR and IZ. Hardness was statistically similar (p=0.30) for all groups. Means and standard deviations of FS (in MPa) were 846.65 ± 81.97 for the PR group, 808.88 ± 117.99 for the IZ group, and 771.81 ± 114.43 for the BL group, with no statistical difference (p>0.05). Weibull moduli were 12.47 for the PR group, 7.24 for the IZ group, and 6.31 for the BL group, with no statistical differences. The PR and BL groups had higher transmittance values and grain sizes than the IZ group (p<0.05). Although the BL group had some fractures that originated in the center of the tensile surface, fractographic analyses showed the same fracture pattern.
Conclusions:
All tested zirconia showed similar VHN, and the monolithic zirconia had similar roughness compared to one of the conventional zirconias. In addition, the monolithic zirconia showed similar flexural strength and Weibull modulus compared to the others even though its mean grain size was larger. The total transmittance of monolithic zirconia was higher than only one of the conventional zirconias tested.
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Affiliation(s)
- LM Candido
- Lucas Miguel Candido, PhD student, Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista, Araraquara, Brazil
| | - LN Miotto
- Larissa Natiele Miotto, master degree, Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista, Araraquara, Brazil
| | - LMG Fais
- Laiza Maria Grassi Fais, postdoctoral research, Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista, Araraquara, Brazil
| | - PF Cesar
- Paulo Francisco Cesar, associate professor, Department of Biomaterials and Oral Biology, São Paulo Dental School, Universidade de São Paulo, São Paulo, Brazil
| | - LAP Pinelli
- Lígia Antunes Pereira Pinelli, associate professor, Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista, Araraquara, Brazil
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88
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Gali S, K R, Murthy BVS, Basu B. Zirconia toughened mica glass ceramics for dental restorations. Dent Mater 2018; 34:e36-e45. [PMID: 29395467 DOI: 10.1016/j.dental.2018.01.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 10/04/2017] [Accepted: 01/09/2018] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The objective of the present study is to understand the role of yttria stabilized zirconia (YSZ) in achieving the desired spectrum of clinically relevant mechanical properties (hardness, elastic modulus, fracture toughness and brittleness index) and chemical solubility of mica glass ceramics. METHODS The glass-zirconia mixtures with varying amounts of YSZ (0, 5, 10, 15 and 20wt.%) were ball milled, compacted and sintered to obtain pellets of glass ceramic-YSZ composites. Phase analysis was carried out using X-ray diffraction and microstructural characterization with SEM revealed the crystal morphology of the composites. Mechanical properties such as Vickers hardness, elastic modulus, indentation fracture toughness and chemical solubility were assessed. RESULTS Phase analysis of sintered pellets of glass ceramic-YSZ composites revealed the characteristic peaks of fluorophlogopite (FPP) and tetragonal zirconia. Microstructural investigation showed plate and lath-like interlocking mica crystals with embedded zirconia. Vickers hardness of 9.2GPa, elastic modulus of 125GPa, indentation toughness of 3.6MPa·m1/2, and chemical solubility of 30μg/cm2 (well below the permissible limit) were recorded with mica glass ceramics containing 20wt.% YSZ. SIGNIFICANCE An increase in hardness and toughness of the glass ceramic-YSZ composites with no compromise on their brittleness index and chemical solubility has been observed. Such spectrum of properties can be utilised for developing a machinable ceramic for low stress bearing inlays, onlays and veneers.
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Affiliation(s)
- Sivaranjani Gali
- Department of Prosthodontics, Faculty of Dental Sciences, M. S. Ramaiah University of Applied Sciences, Bangalore, India
| | - Ravikumar K
- Materials Research Centre, Laboratory for Biomaterials, Indian Institute of Science, Bangalore, India
| | - B V S Murthy
- Department of Prosthodontics, Faculty of Dental Sciences, M. S. Ramaiah University of Applied Sciences, Bangalore, India
| | - Bikramjit Basu
- Materials Research Centre, Laboratory for Biomaterials, Indian Institute of Science, Bangalore, India.
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89
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Silvestri T, Pereira GKR, Guilardi LF, Rippe MP, Valandro LF. Effect of Grinding and Multi-Stimuli Aging on the Fatigue Strength of a Y-TZP Ceramic. Braz Dent J 2018; 29:60-67. [DOI: 10.1590/0103-6440201801735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 10/16/2017] [Indexed: 01/07/2023] Open
Abstract
Abstract This study aimed to investigate the effect of grinding and multi-stimuli aging on the fatigue strength, surface topography and the phase transformation of Y-TZP ceramic. Discs were manufactured according to ISO-6872:2008 for biaxial flexure testing (diameter: 15 mm; thickness: 1.2 mm) and randomly assigned considering two factors “grinding” and “aging”: C- control (as-sintered); CA- control + aging; G- ground; GA- ground + aging. Grinding was carried out with coarse diamond burs under water-cooling. Aging protocols consisted of: autoclave (134°C, 2 bars pressure, 20 hours), followed by storage for 365 days (samples were kept untouched at room temperature), and by mechanical cycling (106 cycles by 20 Hz under a load of 50% from the biaxial flexure monotonic tests). Flexural fatigue strengths (20,000 cycles; 6 Hz) were determined under sinusoidal cyclic loading using staircase approach. Additionally, surface topography analysis by FE-SEM and phase transformation analysis by X-ray Diffractometry were performed. Dixon and Mood methodology was used to analyze the fatigue strength data. Grinding promotes alterations of topographical pattern, while aging apparently did not alter it. Grinding triggered t-m phase transformation without impacting the fatigue strength of the Y-TZP ceramic; and aging promoted an intense t-m transformation that resulted in a toughening mechanism leading to higher fatigue strength for as-sintered condition, and a tendency of increase for ground condition (C < CA; G = GA). It concludes that grinding and aging procedures did not affect deleteriously the fatigue strength of the evaluated Y-TZP ceramic, although, it promotes surface topography alterations, except to aging, and t-m phase transformation.
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90
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Wille S, Zumstrull P, Kaidas V, Jessen LK, Kern M. Low temperature degradation of single layers of multilayered zirconia in comparison to conventional unshaded zirconia: Phase transformation and flexural strength. J Mech Behav Biomed Mater 2018; 77:171-175. [DOI: 10.1016/j.jmbbm.2017.09.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 09/06/2017] [Indexed: 12/22/2022]
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Guilardi LF, Pereira GKR, Wandscher VF, Rippe MP, Valandro LF. Mechanical behavior of yttria-stabilized tetragonal zirconia polycrystal: Effects of different aging regimens. Braz Oral Res 2017; 31:e94. [PMID: 29236899 DOI: 10.1590/1807-3107bor-2017.vol31.0094] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/02/2017] [Indexed: 11/22/2022] Open
Abstract
This study aimed to characterize and compare the effect of different aging regimens on surface characteristic (topography and roughness), structural stability (phase transformation) and mechanical performance (Weibull analysis) of a Y-TZP ceramic. Discs (15 × 1.2 mm; VITA In-Ceram YZ) were prepared according to ISO 6872-2015 for biaxial flexural strength testing and randomly assigned into five groups (n = 30): as-sintered, no aging treatment (CTRL); 20 h in autoclave at 134°C, 2 bar pressure (AUT); intermittent mechanical loading at 20 Hz/106 load pulses (MechLoad); AUT followed by MechLoad (AUT+MechLoad); and storage in distilled water at 37°C, for 1 year (STO). The following analyses were performed: roughness (n = 30), surface topography (n = 2), phase transformation (n = 2) and biaxial flexure strength (n = 30). Phase transformation (increase of m-phase content) was shown to be a spontaneous, unavoidable and time-dependent process, occurring even under ambient conditions (dry storage after 1 year = 6.0% increase), and is considerably accelerated in the presence of moisture (STO = 17.6%; AUT= 63.1%; and AUT+MechLoad = 59.9%). For roughness parameters, only Ra was affected by aging, and the highest values were observed for AUT+MechLoad (0.25 ± 0.07 µm). For Weibull analysis, structural reliability (Weibull moduli) and characteristic strength were not impaired after aging, and some aging conditions led to increased values (highest weibull moduli in AUT, and highest characteristic strength in STO). Phase transformation proves to be a time-dependent spontaneous mechanism that is accelerated in the presence of different stimuli. However, none of the aging regimens had a negative effect on the characteristic strength and structural reliability of Y-TZP ceramic.
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Affiliation(s)
- Luís Felipe Guilardi
- Universidade Federal de Santa Maria - UFSM, Faculty of Odontology, Santa Maria, RS, Brazil
| | | | - Vinícius Felipe Wandscher
- Centro Universitário Franciscano - Unifra, Faculty of Odontology, Prosthodontic Unit, Santa Maria, RS, Brazil
| | - Marília Pivetta Rippe
- Universidade Federal de Santa Maria - UFSM, Faculty of Odontology, Prosthodontic Unit, Santa Maria, RS, Brazil
| | - Luiz Felipe Valandro
- Universidade Federal de Santa Maria - UFSM, Faculty of Odontology, Prosthodontic Unit, Santa Maria, RS, Brazil
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92
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PRADO RD, PEREIRA GKR, BOTTINO MA, MELO RMD, VALANDRO LF. Effect of ceramic thickness, grinding, and aging on the mechanical behavior of a polycrystalline zirconia. Braz Oral Res 2017; 31:e82. [DOI: 10.1590/1807-3107bor-2017.vol31.0082] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 08/14/2017] [Indexed: 11/22/2022] Open
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93
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Dutra DAM, Pereira GKR, Kantorski KZ, Exterkate RAM, Kleverlaan CJ, Valandro LF, Zanatta FB. Grinding With Diamond Burs and Hydrothermal Aging of a Y-TZP Material: Effect on the Material Surface Characteristics and Bacterial Adhesion. Oper Dent 2017; 42:669-678. [DOI: 10.2341/16-108-l] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
The aim of this study was to evaluate the effect of grinding with diamond burs and low-temperature aging on the material surface characteristics and bacteria adhesion on a yttrium-stabilized tetragonal zirconia polycrystalline (Y-TZP) surface. Y-TZP specimens were made from presintered blocks, sintered as recommended by the manufacturer, and assigned into six groups according to two factors—grinding (three levels: as sintered, grinding with extra-fine diamond bur [25-μm grit], and grinding with coarse diamond bur [181-μm grit]) and hydrothermal aging—to promote low-temperature degradation (two levels: presence/absence). Phase transformation (X-ray diffractometer), surface roughness, micromorphological patterns (atomic force microscopy), and contact angle (goniometer) were analyzed. Bacterial adhesion (colony-forming units [CFU]/biofilm) was quantified using an in vitro polymicrobial biofilm model. Both the surface treatment and hydrothermal aging promoted an increase in m-phase content. Roughness values increased as a function of increasing bur grit sizes. Grinding with a coarse diamond bur resulted in significantly lower values of contact angle (p<0.05) when compared with the extra-fine and control groups, while there were no differences (p<0.05) after hydrothermal aging simulation. The CFU/biofilm results showed that neither the surface treatment nor hydrothermal aging simulation significantly affected the bacteria adherence (p>0.05). Grinding with diamond burs and hydrothermal aging modified the Y-TZP surface properties; however, these properties had no effect on the amount of bacteria adhesion on the material surface.
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Affiliation(s)
- DAM Dutra
- Danilo Antonio Milbradt Dutra, DDS, MSc, Post-graduate Program in Oral Science, Federal University of Santa Maria, Santa Maria, Brazil
| | - GKR Pereira
- Gabriel Kalil Rocha Pereira, DDS, MSc, PhD, Graduate Program in Dentistry, School of Dentistry, Meridional Faculty – IMED, Passo Fundo, Brazil
| | - KZ Kantorski
- Karla Zanini Kantorski, DDS, MSc, PhD, Post-graduate Program in Oral Science, Federal University of Santa Maria, Santa Maria, Brazil
| | - RAM Exterkate
- Rob A. M. Exterkate, BSc, PhD, Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam, and Vrije Universiteit, Amsterdam, Netherlands
| | - CJ Kleverlaan
- Cornelis Johannes Kleverlaan, BCh, PhD, Department of Dental Material Sciences, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam, and Vrije Universiteit, Amsterdam, Netherlands
| | - LF Valandro
- Luiz Felipe Valandro, DDS, MSc, PhD, Post-graduate Program in Oral Science, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil
| | - FB Zanatta
- Fabrício Batistin Zanatta, DDS, MSc, PhD, Post-graduate Program in Oral Science, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil
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94
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Zucuni CP, Guilardi L, Rippe M, Pereira GK, Valandro L. Fatigue strength of yttria-stabilized zirconia polycrystals: Effects of grinding, polishing, glazing, and heat treatment. J Mech Behav Biomed Mater 2017; 75:512-520. [DOI: 10.1016/j.jmbbm.2017.06.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 02/04/2023]
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95
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Lai X, Si W, Jiang D, Sun T, Shao L, Deng B. Effects of small-grit grinding and glazing on mechanical behaviors and ageing resistance of a super-translucent dental zirconia. J Dent 2017; 66:23-31. [PMID: 28916163 DOI: 10.1016/j.jdent.2017.09.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 07/31/2017] [Accepted: 09/11/2017] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES The purpose of this study is to elucidate the effects of small-grit grinding on the mechanical behaviors and ageing resistance of a super-translucent dental zirconia and to investigate the necessity of glazing for the small-grit ground zirconia. METHODS Small-grit grinding was performed using two kinds of silicon carbide abrasive papers. The control group received no grinding. The unground surfaces and the ground surfaces were glazed by an experienced dental technician. Finally, the zirconia materials were thermally aged in water at 134°C for 5h. After aforementioned treatments, we observed the surface topography and the microstructures, and measured the extent of monoclinic phase, the nano-hardness and nano-modulus of the possible transformed zone and the flexural strength. RESULTS Small-grit grinding changed the surface topography. The zirconia microstructure did not change obviously after surface treatments and thermal ageing; however, the glaze in contact with zirconia showed cracks after thermal ageing. Small-grit grinding did not induce a phase transformation but improved the flexural strength and ageing resistance. Glazing prevented zirconia from thermal ageing but severely diminished the flexural strength. The nano-hardness and nano-modulus of the surface layer were increased by ultrafine grinding. CONCLUSIONS The results suggest that small-grit grinding is beneficial to the strength and ageing resistance of the super-translucent dental zirconia; however, glazing is not necessary and even impairs the strength for the super-translucent dental zirconia. CLINICAL SIGNIFICANCE This study is helpful to the researches about dental grinding tools and maybe useful for dentists to choose reasonable zirconia surface treatments.
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Affiliation(s)
- Xuan Lai
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Wenjie Si
- School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Danyu Jiang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Shanghai, 200050, China
| | - Ting Sun
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Longquan Shao
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
| | - Bin Deng
- Department of the Prosthodontics, The General Hospital of Chinese PLA, Beijing, 100853, China.
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96
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Ocelík V, Schepke U, Rasoul HH, Cune MS, De Hosson JTM. On the bulk degradation of yttria-stabilized nanocrystalline zirconia dental implant abutments: an electron backscatter diffraction study. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2017; 28:121. [PMID: 28685232 PMCID: PMC5500667 DOI: 10.1007/s10856-017-5927-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 06/16/2017] [Indexed: 06/07/2023]
Abstract
Degradation of yttria-stabilized zirconia dental implants abutments due to the tetragonal to monoclinic phase transformation was studied in detail by microstructural characterization using Electron Back Scatter Diffraction (EBSD). The amount and distribution of the monoclinic phase, the grain-size distribution and crystallographic orientations between tetragonal and monoclinic crystals in 3 mol.% yttria-stabilized polycrystalline zirconia (3Y-TZP) were determined in two different types of nano-crystalline dental abutments, even for grains smaller than 400 nm. An important and novel conclusion is that no substantial bulk degradation of 3Y-TZP dental implant abutments was detected after 1 year of clinical use.
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Affiliation(s)
- V Ocelík
- Department of Applied Physics, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands.
| | - U Schepke
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, Netherlands
| | - H Haji Rasoul
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, Netherlands
| | - M S Cune
- Department of Fixed and Removable Prosthodontics and Biomaterials, Center for Dentistry and Oral Hygiene, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, Netherlands
| | - J Th M De Hosson
- Department of Applied Physics, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
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97
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Muñoz EM, Longhini D, Antonio SG, Adabo GL. The effects of mechanical and hydrothermal aging on microstructure and biaxial flexural strength of an anterior and a posterior monolithic zirconia. J Dent 2017; 63:94-102. [PMID: 28591620 DOI: 10.1016/j.jdent.2017.05.021] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 05/03/2017] [Accepted: 05/30/2017] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES To evaluate the effect of hydrothermal aging (H), mechanical cycling (M), and the combination of hydrothermal plus mechanical cycling (H+M) on biaxial flexural strength (BFS) and microstructure of two monolithic zirconias, indicated for anterior (AMZ) or posterior restorations (PMZ) and a conventional zirconia (IZr). METHODS Disc specimens of each material (n=12) were submitted to: i) H (8h in autoclave at 134°C); ii) M (106 cycles, at 40% of BFS); and iii) H+M. BFS was measured (ISO-6872) and Weibull modulus (m) and the characteristic strength (σ0) were calculated. crystalline phase composition analyzed by XRD, and grain size measured by MEV analysis. RESULTS XRD analysis showed AMZ was not susceptible to monoclinic transformation in any treatment. Conventional zirconia (IZr) and PMZ had monoclinic transformation only after H and H+M. BFS of AMZ was lower than PMZ and IZr. Cubic phase was found in all conditions for AMZ and IZr, while it was identified in PMZ only after H and H+M. BFS of AMZ was affected by M and H+M. For IZr and PMZ the unique difference detected in BFS was in the comparison of H to M. H treatment induced lower Weibull modulus, but characteristic strength was compatible with the BFS results. AMZ grain size (μm2) was 8.6 times larger than PMZ grains, and 13.6 times larger than IZr grains. CONCLUSIONS AMZ showed the largest mean grain size, had the lowest BFS values, and was affected when mechanical cycling was involved. Monoclinic transformation was not found in any treatment for AMZ, but was found in IZr and PMZ when hydrothermal aging was used alone or when combined with mechanical cycling. PMZ showed similar behavior to the IZr. H induced to higher fracture probability. CLINICAL SIGNIFICANCE Translucent monolithic dental zirconia available on the market may behave differently under simulated oral aging. The relationship between composition and microstructure determines their properties presumably, and clinical performance.
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Affiliation(s)
- Eduardo Mariscal Muñoz
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Univ Estadual Paulista-UNESP, São Paulo, Brazil
| | - Diogo Longhini
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Univ Estadual Paulista-UNESP, São Paulo, Brazil
| | - Selma Gutierres Antonio
- Department of Physical Chemistry, Araraquara Institute of Chemistry, Univ Estadual Paulista-UNESP, São Paulo, Brazil
| | - Gelson Luis Adabo
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Univ Estadual Paulista-UNESP, São Paulo, Brazil.
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AL‐Rabab'ah M, Hamadneh W, Alsalem I, Khraisat A, Abu Karaky A. Use of High Performance Polymers as Dental Implant Abutments and Frameworks: A Case Series Report. J Prosthodont 2017; 28:365-372. [DOI: 10.1111/jopr.12639] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2017] [Indexed: 11/30/2022] Open
Affiliation(s)
- Mohammad AL‐Rabab'ah
- Department of Conservative Dentistry, School of DentistryThe University of Jordan Amman Jordan
| | | | | | - Ameen Khraisat
- Department of Conservative Dentistry, School of DentistryThe University of Jordan Amman Jordan
| | - Ashraf Abu Karaky
- Department of Oral and Maxillofacial Surgery, Oral Medicine and Periodontology, School of DentistryThe University of Jordan Amman Jordan
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Pozzobon JL, Pereira GKR, Wandscher VF, Dorneles LS, Valandro LF. Mechanical behavior of yttria-stabilized tetragonal zirconia polycrystalline ceramic after different zirconia surface treatments. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 77:828-835. [PMID: 28532098 DOI: 10.1016/j.msec.2017.03.299] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 03/31/2017] [Indexed: 12/22/2022]
Abstract
This study investigated the effects of different zirconia surface conditioning methods on the biaxial flexure strength, surface characteristics and fractographic analysis of a Y-TZP ceramic. Disc-shaped specimens were manufactured according to ISO 6872-2008 for biaxial flexure strength testing, and then randomly assigned into seven groups (n=30). Control (CTRL): without treatment; Tribochemical silica coating (TBS): specimens were sandblasted with silica-coated aluminum oxide particles (CoJet-Sand) for 10s; Silica nanofilm (SNF): specimens were silica coated with a 5nm SiO2 nanofilm; and four protocols of low-fusing porcelain glaze (GLZ): etching with 10% hydrofluoric acid gel (HF) for 1min (GLZ1), 5min (GLZ5), 10min (GLZ10) and 15min (GLZ15). Phase transformation, roughness, micro-morphological, flexural analysis tests, and fractographic analyses were performed. X-ray diffraction (XRD) analysis showed that the TBS promoted the highest m-phase content (20.35). However, for the GLZ groups, XRD analysis was not sensitive enough to obtain an accurate reading for phase transformation. The GLZ group had the highest roughness values. The TBS group had the highest characteristic strength (1291.38MPa), followed by SNF (999.26MPa). These results suggest that (TBS) and (SNF) treatments did not reduce the mechanical properties, while (GLZ) led to a degradation in the mechanical properties.
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Affiliation(s)
- Joao Luiz Pozzobon
- MSciD-PhD Graduate Programs in Oral Science (Prosthodontics Units), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | - Gabriel Kalil Rocha Pereira
- MSciD-PhD Graduate Programs in Oral Science (Prosthodontics Units), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | - Vinicius Felipe Wandscher
- MSciD-PhD Graduate Programs in Oral Science (Prosthodontics Units), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | | | - Luiz Felipe Valandro
- MSciD-PhD Graduate Programs in Oral Science (Prosthodontics Units), Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
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100
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Zucuni CP, Guilardi LF, Fraga S, May LG, Pereira GKR, Valandro LF. CAD/CAM machining Vs pre-sintering in-lab fabrication techniques of Y-TZP ceramic specimens: Effects on their mechanical fatigue behavior. J Mech Behav Biomed Mater 2017; 71:201-208. [PMID: 28343087 DOI: 10.1016/j.jmbbm.2017.03.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 03/11/2017] [Accepted: 03/14/2017] [Indexed: 12/22/2022]
Abstract
This study evaluated the effects of different pre-sintering fabrication processing techniques of Y-TZP ceramic (CAD/CAM Vs. in-lab), considering surface characteristics and mechanical performance outcomes. Pre-sintered discs of Y-TZP ceramic (IPS e.max ZirCAD, Ivoclar Vivadent) were produced using different pre-sintering fabrication processing techniques: Machined- milling with a CAD/CAM system; Polished- fabrication using a cutting device followed by polishing (600 and 1200 SiC papers); Xfine- fabrication using a cutting machine followed by grinding with extra-fine diamond bur (grit size 30 μm); Fine- fabrication using a cutting machine followed by grinding with fine diamond bur (grit size 46 μm); SiC- fabrication using a cutting machine followed by grinding with 220 SiC paper. Afterwards, the discs were sintered and submitted to roughness (n=35), surface topography (n=2), phase transformation (n=2), biaxial flexural strength (n=20), and biaxial flexural fatigue strength (fatigue limit) (n=15) analyses. No monoclinic-phase content was observed in all processing techniques. It can be observed that obtaining a surface with similar characteristics to CAD/CAM milling is essential for the observation of similar mechanical performance. On this sense, grinding with fine diamond bur before sintering (Fine group) was the best mimic protocol in comparison to the CAD/CAM milling.
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Affiliation(s)
- C P Zucuni
- MSciD-PhD Graduate Programs in Oral Science, Prosthodontics Units, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | - L F Guilardi
- MSciD-PhD Graduate Programs in Oral Science, Prosthodontics Units, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | - S Fraga
- MSciD-PhD Graduate Programs in Oral Science, Prosthodontics Units, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | - L G May
- MSciD-PhD Graduate Programs in Oral Science, Prosthodontics Units, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
| | - G K R Pereira
- MSciD-PhD Graduate Programs in Oral Science, Prosthodontics Units, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil; MSciD Graduate Program, School of Dentistry, Meridional Faculty - IMED, Passo Fundo, Rio Grande do Sul, Brazil.
| | - L F Valandro
- MSciD-PhD Graduate Programs in Oral Science, Prosthodontics Units, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil.
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