Bond Strength of self-adhesive cements: effect of restorative material and polimerization time

• Grant number: 09/10879-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2009
• End date: September 30, 2010
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Luís Roberto Marcondes Martins
• Grantee: Camila Bortoletto Schoba
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

This study aims to evaluate bond strength (MPa) of resin cement Rely X U100 adhesive to dentin of human third molars (n = 10). Two factors are under study: 1 - Type of restoration on the cement used: ceramic (CP) or Metal-(MC) and 2 - time the test is conducted after polymerization: after 10 minutes (T1), after 1 hour (T2) and after 24 hours (T3). The analysis method employed will the microcisalhamento. The all-ceramic restorations reinforced by lithium disilicate (2 mm thick and 1.0 mm in diameter) or fused to metal (0.5 mm and 1.5 mm metal feldspathic ceramic with a diameter of 1 mm) will be fixed with cement adhesive under load of 500g on the occlusal dentin of human third molars as manufacturer's instructions. The test includes a device that fixes the set tooth / restoration and an orthodontic wire that is bypassed around the interface of two and at a speed of 1 mm / min, a shear force is applied until the union is break. The average for each group shall be calculated in MPa The data will be tabulated and submitted. Factor analysis of (2X3) and Tukey's multiple comparison of means. The bodies of evidence will be stored, and the fracture pattern assessed by stereoscopic Magnifier - 4X. The fracture pattern is classified into Type 1: cohesive failure in resin cement; Type 2: adhesive failure between the indirect restoration and resin cement, Type 3: mixed failure characterized by exposure of the dentin surface and the presence of resin cement and be expressed in percentage (%).