Y-TZP zirconia regeneration firing: Microstructural and crystallographic changes after grinding

Author(s)

Obelenis Ryan, Daniel Patrick ^[1] ; Grassi Fais, Laiza Maria ^[1] ; Antonio, Selma Gutierrez ^[2] ; Hatanaka, Gabriel Rodrigues ^[1] ; Candido, Lucas Miguel ^[1] ; Pereira Pinelli, Ligia Antunes ^[1]

Affiliation

^[1] UNESP Univ Estadual Paulista, Araraquara Dent Sch, Dept Dent Mat & Prosthodont, Humaita St, 1680, BR-14801903 Sao Paulo, Araraquara - Brazil

^[2] UNESP Univ Estadual Paulista, Araraquara Inst Chem, Dept Phys Chem, Prof Francisco Degni St, 55, BR-14800060 Sao Paulo, Araraquara - Brazil

• Document type: Journal article
• Source: DENTAL MATERIALS JOURNAL; v. 36, n. 4, p. 447-453, AUG 2017.
• Web of Science Citations: 7

Abstract

This study evaluated microstructural and crystallographic phase changes after grinding (G) and regeneration firing/anneling (R) of Y-TZP ceramics. Thirty five bars (LavaTM 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. (AU)

• FAPESP's process: 13/21438-4 - Microstructural characterization of partially stabilized zirconia after grinding and ressintering
• Grantee: Daniel Patrick Obelenis Ryan
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 11/11509-6 - Flexural strength of Y-TZP dental ceramic after different grinding procedures and resintered
• Grantee: Ligia Antunes Pereira Pinelli
• Support Opportunities: Regular Research Grants