Effect of refrigeration on bond strenght of one self-etching adhesive

Objectives:The purpose of this study was to investigate the tensile bond strengths of an adhesive system applied to dentin at refrigerated and room temperatures. Methods: Twenty bovine incisor teeth were obtained, embedded in self-cured acrylic resin, abraded on a lathe under water spray and polished to 320 and 600 grit to form standardized dentin surface. The adhesive system Clearfil SE Bond, Kuraray, Japan was applied to dentin according to the manufacturer instructions at refrigerated temperature (4oC) and at room temperature (23 oC), before bonding resin-based composite (Charisma, Kulzer, Germany). The specimens were stored in distilled water at 37oC for 24 hours and submitted to tensile bond strength tests on a universal testing machine (EMIC DL-3000) at a crosshead speed of 0.5 mm/min. Results: The resulting data were statistically analyzed using analysis of variance and Tukey's test. No statistical differences were found when the adhesive system was applied at refrigerated and room temperatures. Conclusions: No adverse effects upon tensile bond strength were observed when adhesive system was taken directly from refrigerated storage.