Artículos de revistas
Y-TZP zirconia regeneration firing: Microstructural and crystallographic changes after grinding
Fecha
2017-01-01Registro en:
Dental Materials Journal, v. 36, n. 4, p. 447-453, 2017.
1881-1361
0287-4547
10.4012/dmj.2016-124
2-s2.0-85026366234
0455968557454133
Autor
Universidade Estadual Paulista (Unesp)
Institución
Resumen
This study evaluated microstructural and crystallographic phase changes after grinding (G) and regeneration firing/anneling (R) of Y-TZP ceramics. Thirty five bars (Lava™ and Ice Zirkon) were divided: Y-TZP pre-sintered, control (C), regeneration firing (R), dry grinding (DG), dry grinding+regeneration firing (DGR), wet grinding (WG) and wet grinding+regeneration firing (WGR). Grinding was conducted using a diamond bur and annealing at 1,000°C. The microstructure was analyzed by SEM and the crystalline phases by X-ray diffraction (XRD). XRD showed that pre-sintered specimens contained tetragonal and monoclinic phases, while groups C and R showed tetragonal, cubic and monoclinic phases. After grinding, the cubic phase was eliminated in all groups. Annealing (DGR and WGR) resulted in only tetragonal phase. SEM showed semi-circular cracks after grinding and homogenization of particles after annealing. After grinding, surfaces show tetragonal and monoclinic phases and R can be assumed to be necessary prior to porcelain layering when grinding is performed.