Interference of preventive caries system with microshear bond strength of enamel surface bonded to etch &rinse or self etch adhesive system with nanofilled composite
Ola. M. Sakr1 and Mohammad Almohaimeed 2
1Departments of Operative Dentistry, College of Dentistry ,Qassim University (Saudi Arabia) and Misr University for Science and technology (Egypt)
2 Department of Orthodontics and Pediatric Dentistry, College of Dentistry , Qassim University, Saudi Arabia
Abstract: Purpose: To evaluate the microshear bond strength of self etch and etch &rinse adhesives of nanofilled composite on enamel substrates after fluoride application. Materials and Methods: Forty Enamel samples were obtained from human premolars and randomly divided into 2 groups (n = 10) according to enamel substrates treatment first group samples are painted with fluoride varnish for 20 min and stored in artificial saliva for 24 hours , then divided into 2 subdivisions : first subdivision is treated with etch & rinse adhesive then. 2nd subdivision samples are treated with self etch adhesive. The second group divided into 2 subdivision : first subdivision are treated with etch & rinse adhesive. 2nd subdivision samples are treated with self etch adhesive. All prepared samples ,Prior to adhesive curing, a hollow cylinder (2.0 mm height/0.75mm internal diameter) was placed on the treated surfaces. A nanofilled resin composite was then inserted into the tube and cured. After artificial saliva storage for 24 hrs, the tube was removed and microshear bond strength was determined in a universal testing machine at a crosshead speed of 0.5 mm/min. Results: The mean and standard deviation values of micro-shear bond strength were 15.9 ± 4 MPa and 9.7 ± 3.8 MPa for normal and fluoridated enamel, respectively. Normal enamel showed statistically significantly higher mean micro-shear bond strength than fluoridated enamel. Conclusions: The microshear bond strength decrease in cases of recently fluoridatedenamel.
[Ola. M. Sakr and Mohammed Almohaimeed. Interference of preventive caries system with microshear bond strength of enamel surface bonded to etch &rinse or self etch adhesive system with nanofilled composite.Life Sci J 2013;10(1):1984-1987] (ISSN:1097-8135). http://www.lifesciencesite.com.
Key Words: preventive therapy, microshear bond strength, adhesion , nanofilled composite.