Masanao Inokoshi1, Kim Vanmeensel2, Fei Zhang2, Jan De Munck1, George Eliades3, Shunsuke Minakuchi4, Ignace Naert1, Bart Van Meerbeek5, Jozef Vleugels2. 1. KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7, blok a bus 7001, B-3000 Leuven, Belgium. 2. Department of Materials Engineering, KU Leuven (University of Leuven), Kasteelpark Arenberg 44, B-3001 Heverlee, Belgium. 3. Department of Biomaterials, University of Athens, 2 Thivon Str., Goudi, 115 27 Athens, Greece. 4. Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-8549, Japan. 5. KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7, blok a bus 7001, B-3000 Leuven, Belgium. Electronic address: bart.vanmeerbeek@med.kuleuven.be.
Abstract
UNLABELLED: The influence of surface treatment on the low-temperature degradation (LTD) of tetragonal zirconia polycrystalline (TZP) is still unclear. OBJECTIVES: The effect of surface treatments on the LTD behavior of zirconia was investigated. METHODS: Fully-sintered specimens of seven commercial dental zirconia (Aadva, GC; In-CeramYZ, VITA; IPS e.max ZirCAD, Ivoclar Vivadent; LAVA Frame and LAVA Plus, 3M ESPE; NANOZR, Panasonic; ZirTough, Kuraray Noritake) were provided by the manufacturers with specimen dimensions of approximately 10mm×5mm×3mm. For each zirconia grade, samples were kept 'as sintered' (untreated) or were subjected to one of the three surface treatments: rough polished, sandblasted with Al2O3, tribochemical silica sandblasted (n=3/group). The tetragonal to monoclinic transformation was evaluated by X-ray diffraction at several intervals during LTD testing up to 40h in steam in an autoclave (134°C, 2bar). RESULTS: The five yttria-stabilized TZP (Y-TZP: Aadva, In-CeramYZ, IPS e.max ZirCAD, LAVA Frame, LAVA Plus) zirconia showed a similar trend in LTD behavior. The Al2O3 sandblasted zirconia showed the highest monoclinic volume fraction. The as sintered (untreated) zirconia degraded faster than the surface-treated zirconia. Although the surface-treated ceria-stabilized TZP/alumina (Ce-TZP/Al2O3: NANOZR) zirconia had a higher initial monoclinic volume fraction compared to the Y-TZP zirconia, it showed a stronger aging resistance. The as sintered (untreated) Y-TZP/alumina (Y-TZP/Al2O3: ZirTough) zirconia showed a strong aging resistance, whereas the surface-treated Y-TZP/Al2O3 zirconia degraded slightly. SIGNIFICANCE: Surface treatment improved the aging resistance of Y-TZP zirconia. Surface treatment did not affect the LTD behavior of Ce-TZP/Al2O3 zirconia, while surface treatment decreased the aging resistance of Y-TZP/Al2O3 zirconia.
UNLABELLED: The influence of surface treatment on the low-temperature degradation (LTD) of tetragonal zirconia polycrystalline (TZP) is still unclear. OBJECTIVES: The effect of surface treatments on the LTD behavior of zirconia was investigated. METHODS: Fully-sintered specimens of seven commercial dental zirconia (Aadva, GC; In-CeramYZ, VITA; IPS e.max ZirCAD, Ivoclar Vivadent; LAVA Frame and LAVA Plus, 3M ESPE; NANOZR, Panasonic; ZirTough, Kuraray Noritake) were provided by the manufacturers with specimen dimensions of approximately 10mm×5mm×3mm. For each zirconia grade, samples were kept 'as sintered' (untreated) or were subjected to one of the three surface treatments: rough polished, sandblasted with Al2O3, tribochemical silica sandblasted (n=3/group). The tetragonal to monoclinic transformation was evaluated by X-ray diffraction at several intervals during LTD testing up to 40h in steam in an autoclave (134°C, 2bar). RESULTS: The five yttria-stabilized TZP (Y-TZP: Aadva, In-CeramYZ, IPS e.max ZirCAD, LAVA Frame, LAVA Plus) zirconia showed a similar trend in LTD behavior. The Al2O3 sandblasted zirconia showed the highest monoclinic volume fraction. The as sintered (untreated) zirconia degraded faster than the surface-treated zirconia. Although the surface-treated ceria-stabilized TZP/alumina (Ce-TZP/Al2O3: NANOZR) zirconia had a higher initial monoclinic volume fraction compared to the Y-TZP zirconia, it showed a stronger aging resistance. The as sintered (untreated) Y-TZP/alumina (Y-TZP/Al2O3: ZirTough) zirconia showed a strong aging resistance, whereas the surface-treated Y-TZP/Al2O3 zirconia degraded slightly. SIGNIFICANCE: Surface treatment improved the aging resistance of Y-TZP zirconia. Surface treatment did not affect the LTD behavior of Ce-TZP/Al2O3 zirconia, while surface treatment decreased the aging resistance of Y-TZP/Al2O3 zirconia.
Authors: Taciana Emília Leite Vila-Nova; Isabelle Helena Gurgel de Carvalho; Dayanne Monielle Duarte Moura; André Ulisses Dantas Batista; Yu Zhang; Carlos Alberto Paskocimas; Marco Antonio Bottino; Rodrigo Othávio de Assunção E Souza Journal: Dent Mater Date: 2020-01-31 Impact factor: 5.304