Banca de QUALIFICAÇÃO: JOÃO VITOR DO NASCIMENTO SANTOS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : JOÃO VITOR DO NASCIMENTO SANTOS
DATE: 20/05/2025
TIME: 14:00
LOCAL: DEPARTAMENTO DE ODONTOLOGIA-SALA DE AULA DO SETOR DA PRÓTESE
TITLE:

EFFECT OF A BOROSILICATE BIOGLASS AND DIFFERENT SURFACE TREATMENTS ON THE BIAXIAL FLEXIBLE STRENGTH OF MONOLITHIC ZIRCONIAS SUBJECTED TO MECHANICAL FATIGUE

KEY WORDS:

Dental prosthesis. Ultra-translucent zirconia. Multilayer zirconia. Mechanical properties.

PAGES: 45
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUBÁREA: Materiais Odontológicos
SUMMARY:

Objective: To evaluate the influence of different surface treatments, including an innovative treatment with borosilicate bioglass, on the biaxial flexural strength of ultra-transparent and multilayer dental zirconia ceramics cemented with resin cement and subjected to mechanical fatigue. Materials and Methods: Eighty ceramic discs (12 mm in diameter and 1.5 mm thick, according to ISO 6872) will be fabricated using ultra-translucent zirconia (4Y-PSZ, Nexx Zr+ White, Sagemax Bioceramics) (n=40) and multilayer zirconia (5Y-PSZ/4Y-PSZ, Nexx Zr+ Multi, Sagemax Bioceramics) (n=40). After sintering, the discs will be randomized and divided into eight groups of ten according to the surface treatment: control (Monobond N primer), air abrasion with 50 µm Al2O3 + primer, CoJet + primer, and infiltration with borosilicate glass. After the surface treatments are applied, the samples will be analyzed using optical profilometry (CCI MP, Taylor Hobson, UK). A thin layer of dual-cure resin cement (Variolink Esthetic DC) it will be applied to the surface, which will then be light-cured for 40 seconds. All samples of each ceramic type will undergo mechanical fatigue testing (6 bar load, 1,200,000 cycles at a frequency of 4 Hz). Then, biaxial flexural strength testing will be performed (Instron 3365 at 1 mm/min and 5,000 kgf). Fractured samples from the biaxial flexural test will undergo fractography analysis and scanning electron microscopy (SEM). Additional samples will be prepared for energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses. The results will be statistically analyzed using a three-way ANOVA, a Tukey's test (α = 0.05), and a Weibull analysis.

COMMITTEE MEMBERS:
Presidente - 1640419 - RODRIGO OTHAVIO DE ASSUNCAO E SOUZA
Interno - 1031499 - LAERCIO ALMEIDA DE MELO
Externa à Instituição - GABRIELA DE ALENCAR PINTO MAGALHÃES