Nanoindentation, dentin permeability and bond strength evaluations of restorations with HEMA-free adhesives: effects of cross-linkers agents and pH-cycling

• Grant number: 13/02386-3
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: September 01, 2013
• End date: August 31, 2014
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Marcelo Giannini
• Grantee: Renata Bacelar Cantanhede de Sá
• Supervisor: Ana Karina Bedran-Russo
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil
• Institution abroad: University of Illinois at Chicago (UIC), United States
• Associated to the scholarship: 11/11415-1 - Study of dentin-HEMA-free adhesive bonding: dentin sealing evaluation, micropermeability and immediately and long lasting bond strength to dentin., BP.DR

Abstract

The aim of this study will be to evaluate the effect of cross-linker agents and pH-cycling on composite restorations made with adhesive systems without HEMA monomer, using nanoindentation, dentin permeability and bond strength methodologies. The restorations will be evaluated after 24 hours and six months of water storage. The control group will be an adhesive with HEMA monomer and the experimental groups will comprise two adhesives without HEMA and one adhesive system with HEMA only in the primer solution. For the nanoindentation analysis test will be analyzed the elastic modulus and nanohardness of the adhesive layer, hybrid layer and underlying dentin in normal conditions, under the effect of cross-linker agents and cariogenic challenge. To perform the bond strength evaluation after cross-linker agents application and pH-cycling will be used the microtensile bond strength test. For dentin permeability analysis will be evaluated the dentin sealing ability of the adhesives using hydraulic conductivity measurements of the dentin tissue in normal conditions or after application of cross-linker agents. (AU)