Effect of caseinephosphopeptide-amorphose calcium phosphate application on the microtensile bond strength to carious affected dentin using etch-and-resine and self-etch adhesive systems

Abstract

After removing infected dentin for conservative cavity preparation, much of cavity walls were coated with caries affected dentin(CAD) that can be remineralized by casein phosphopeptide - amorphous calcium phosphate(CPP-ACP). The objective of this study was to evaluate the effect of CPP-ACP application on the micro tensile bond strength (?TBS) to CAD and compare it with ?TBS of normal dentin (ND) and CAD using etch-and-rinse and self-etch adhesive systems. Methods: Thirty two human molars extracted because of periodontal problems with the coronal dentin caries extended approximately half way in periapical radiography was selected .After occlusal enamel and dentin removing, to obtain CAD the samples were ground using the combined criteria of visual examination, sharp excavator tactile and caries detector solution. Teeth were randomly assigned to two groups (n=16) according to the adhesive were used Single Bond (SB) and Clearfil SE Bond (CSE). After composite bonding the teeth were sectioned and resin dentin bonded interface about 1 to 1/5mm sticks were obtained. ?TBS of each group according to substrate (dentin) in three sub groups ND (n=12), CAD (N=12) and CAD-CPP (N=12) were measured by micro tensile bond strength tester at 0/5mm/min crosshead speed. Data were analyzed by statistical tests Two-Way ANOVA, an independent T test and the Bonferroni and Tukey tests with significance level P < 0 / 05. Result: Etch & rinse Adhesive (Single Bond) has high bond strength to ND and CAD. ?TBS of self etch Adhesive (Clearfil SE Bond) was high to ND but significantly reduced when applied to CAD. CPP-ACP application increase ?TBS of CSE to CAD, but it was not statistically significant. Conclusion: CPP-ACPapplication can improve bond strength of self etch adhesive systems to the CAD.