Influence of EDC solution application on resin-dentin bond degradation

• Grant number: 11/20702-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2012
• End date: December 31, 2012
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Josimeri Hebling Costa
• Grantee: Claudia Cristina Delgado
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Despite the evolution in the chemistry of adhesive systems, the current marked materials still result in resin-dentin bonds susceptible to both hydrolytic and enzymatic degradation. One of the problems that still needs to be overcome is the discrepancy between the depth of dentin demineralization after acid conditioning and the subsequent infiltration of that zone by the adhesive system monomers. As a result, it has been demonstrated that collagen fibrils are kept deprived from mineral or polymeric protection in the base of the hybrid layer, which are prone to deterioration over time. A research front has been investigating approaches to make these fibrils less susceptible to hydrolytic and endogenous enzymes-mediated (MMPs) degradation by increasing the number of cross-linkers among them. In this way, the aim of the present study will be to investigate the effect of EDC application on the long term bond strength of a one-step etch-and-rinse adhesive system to dentin. Flat dentin surfaces will be produced on sound molars (n=72). The dentin will be etched with phosphoric acid and treated with EDC (carbodiimide) for 30 (n=24) or 60 s (n=24). In the control group distilled water will be used on the demineralized dentin (n=24). Then, Single Bond 2 will be applied and a composite resin block will be built up. Specimens with a cross-section adhesive area of 0.81 mm2 will be prepared and submitted to the microtensile test after 24 hours or 6 months of storage in artificial saliva or mineral oil. The statistical tests will be selected based on the distribution and homoscedasticity of the data. The level of significance will be established as 5%.(AU)