Reliability of bilayered zirconia systems based on recycled 3Y-TZP for dental applications

• Grant number: 24/19935-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: December 31, 2025
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Ernesto Byron Benalcazar Jalkh
• Grantee: Rainã Souza Dias
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil
• Associated research grant: 21/06730-7 - Towards sustainable zirconia recycled from milling waste and boosted by glass infiltration for restorative use, and of the development of strong, graded, and aging resistant multilayered zirconia blocks, AP.JP2

Abstract

The current project, supervised by the postdoctoral researcher associated with the FAPESP JP-2021/06730-7 grant, aims to synthesize an experimental bilayer zirconia systems (3Y-TZP / 5Y-PSZ) based on commercial and recycled zirconia powders, and to evaluate its mechanical performance through step-stress accelerated life testing and fractographic analysis. The recycled 3Y-TZP powder will be obtained by processing remnants of blocks, following previously established routes. The bilayer systems will be obtained by sequential uniaxial pressing of ceramic powders to create two experimental groups: a control group (3Y/5Y) and one based on recycled zirconia (3Y-R/5Y). After sintering, the microstructure and phase composition of the materials will be evaluated by SEM and XRD, respectively. The mechanical properties will be evaluated using the step-stress accelerated fatigue testing following load profiles described in the FAPESP 2018/03072-6 process with subsequent fractographic analysis. The distribution of failures will be used to determine the Weibull probability curves, and the probability of survival will be calculated based on clinically relevant loads recommended by ISO 6872:2015.