In vitro study of influence of hardness and elasticity module of adhesive sistems and composite resin in bond strenght to human dentin

• Grant number: 08/08764-1
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2009
• End date: July 31, 2011
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Míriam Lacalle Turbino
• Grantee: Míriam Lacalle Turbino
• Host Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The aim of this study is to evaluate hardness and elasticity module of adhesive region of adhesive systems of different formulations immediately and 6 moths after the adhesive procedures. Those values will be compared to microtensile bond strength to human dentin. The hardness and elasticity module of composite resin next to adhesion region, adhesive layer, hybrid layer and dentin will be evaluated. Forty sound human molars will be used and prepared in order to obtain flat dentin surfaces in which the adhesive systems will be applied following manufactures instructions and rein blocks of 5mm will be made. The groups will be divided according the four adhesive systems: Adper Scotchbond Multipurpose,Adper Single Bond 2, Adper SE Plus, Adper Prompt L-Pop. After 24h of storage in distilled water at 37°C restored teeth will be sectioned in order to obtain specimen with a bonded area of around 1mm2. Two specimen of each tooth will be submitted to nanohardness and elasticity module test and other two will be submitted to a SEM evaluation. Half of the specimen will be immediately submitted to the test with a crosshead speed of 0,5mm/min until fracture, the other specimen will be stored for additional 6 month prior to the test. The values resulting of nanohardness tests (hardness and elasticity module) will be compared using ANOVA for the adhesive groups and Pearson correlation to compare with the results obtained in microtensile bond strength tests. (AU)