Influence of the wear and of the thermal treatment on the resistance to the flexing biaxial of zirconia-based ceramics stabilized by yttrium

• Grant number: 11/16716-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2011
• End date: August 31, 2012
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Marco Antonio Bottino
• Grantee: Gabriela Freitas Ramos
• Host Institution: Faculdade de Odontologia (FOSJC). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

Zirconia has been a material widely used as infrastructure of dentures, due to its excellent physical and mechanical properties. Objectives: 1. To assess the influence of wear caused by abrasion sandpaper grits in different roughness, phase transformation percentage, biaxial flexure strength and reliability analysis of a zirconia-based ceramic partially stabilized by yttrium oxide; 2- To evaluate the effect of heat treatment after abrasion with sandpaper of different granulations, the roughness, phase transformation percentage, biaxial flexure strength and reliability analysis of a zirconia-based ceramic partially stabilized by yttrium oxide. Methodology: 105 zirconia discs stabilized by yttrium will be used, and after sintering they will be subjected to abrasion by sandpaper of different granulations (80, 120 and 600), simulating the clinical wear made by different diamond burs. A group without superficial change after sintering will be used as control. Half of the disks that have suffered wear will undergo heat treatment, in order to release the stress generated during wear. An assessment of roughness, an evaluation of the percentage of monoclinic phase and the biaxial flexure test will also be performed. The data will be statistically analyzed by Weibull. Expected results: The most grained sanding will result in higher surface roughness, higher percentage of monoclinic phase, lower flexural strength and lower reliability of the tested ceramic, and the heat treatment will cause reversal of monoclinic to tetragonal phase, leading to similar results of monoclinic phase percentage among groups. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GABRIELA FREITAS RAMOS; GABRIEL KALIL ROCHA PEREIRA; MARINA AMARAL; LUIZ FELIPE VALANDRO; MARCO ANTONIO BOTTINO. Effect of grinding and heat treatment on the mechanical behavior of zirconia ceramic. Brazilian Oral Research, v. 30, n. 1, 2015-12-15. (11/16716-0)

RAMOS, GABRIELA FREITAS; ROCHA PEREIRA, GABRIEL KALIL; AMARAL, MARINA; VALANDRO, LUIZ FELIPE; BOTTINO, MARCO ANTONIO. Effect of grinding and heat treatment on the mechanical behavior of zirconia ceramic. BRAZILIAN ORAL RESEARCH, v. 30, n. 1, p. 8-pg., 2016-01-01. (11/16716-0)