Bond strength of glass fiber posts to dentin cemented by different cementation and photoactivation protocols

• Grant number: 23/11985-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2023
• End date: April 30, 2024
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Flávio Henrique Baggio Aguiar
• Grantee: Vitor Rodrigues Boralli
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The aim of this study will be to evaluate the influence of different cementation and photoactivation protocols on the bond strength to the push-out of glass fiber posts (GFPs) to dentin. Single-rooted bovine teeth will be endodontically treated and restored with GFPs cemented with different dual resin cements and photoactivation protocols. Three groups will be created according to the cementation procedure of anatomized GFPs with translucent composite resin (Filtek Z350 XT, 3M ESPE): C (conventional) - 37% phosphoric acid (Condac, FGM) + Single Bond 2 (3M ESPE) + RelyX" ARC (3M ESPE); U (universal) - Single Bond Universal (3M ESPE) + RelyX" Ultimate (3M ESPE); and A (self-adhesive) - RelyX" U200 (3M ESPE). All materials will be handled in accordance with the manufacturers' instructions. Three subgroups will be created according to the waiting time for photoactivation of resin cements: 0 (control) - photoactivation after insertion of cements in the root canal; 5 - 5 minutes wait; and 10: 10 minute wait. Photoactivation will be performed using a LED (Valo, Ultradent) for 40 seconds with an irradiance of 1,000 mW/cm2. The roots will be cut into thirds (cervical, medium and apical) which will be taken to the universal testing machine (EMIC, DL2000) for the push-out bond strength test and to the scanning electron microscope (JSM-5600LV, JEOL) for qualitative analysis. Data will be submitted to normality (Shapiro-Wilk) and homoscedasticity (Levene) tests for further analysis and choice of appropriate statistical tests (SPSS 20.0).