Analyses of optical and surface properties of stained and glazed CAD/CAM hybrid-ceramic and composite after toothbrushing with different dentifrices and thermocycling

• Grant number: 23/02943-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2023
• End date: April 30, 2024
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: José Maurício dos Santos Nunes Reis
• Grantee: Rafael Ragnolli Guimarães
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The aim of this in vitro study is to evaluate the effects of toothbrushing with conventional and whitening dentifrices followed by thermocycling on color, opalescence, fluorescence, roughness and surface characterization of feldspar porcelain (VITABLOCS Mark II), a hybrid ceramic (VITA Enamic) and a nanoceramic resin (Lava Ultimate) after staining and glazing procedures. Specimens (12 x 10 x 1.5 mm; n=20/material) will be obtained, polished, receive staining and glazing procedures, and will be randomly divided into two groups, according to the dentifrice: CV (n=10; Conventional, Colgate Total 12 Clean Mint ); or WT (n=10; Whitening, Colgate Total 12 Professional Whitening). Regardless of the group, specimens will be submitted to thermomechanical aging by 100,000 toothbrushing cycles, followed by 12,000 thermocycling cycles, corresponding to 10 years of clinical function. The L*, a*, and b* color coordinate data will be obtained with a spectrophotometer (VITA Easyshade V) for the calculation of color changes (”E00) and opalescence parameter (OP) at baseline and after 10 years of aging. Digital images will be obtained with a DSLR camera for analysis of the fluorescence of the samples under UV light at different periods, baseline and 10 years. Surface roughness (Sa) analysis will also be performed in 3D confocal laser microscopy and chemical and elemental characterization in energy dispersive X-ray spectroscopy (EDX). The data will be submitted to normality and homoscedasticity tests to select the statistical method to be used for the analysis of the results with a 95% significance level.