Effect of the two different application techniques of self-etch adhesive systems on shear bond strength of composite to enamel

Abstract

self-etch adhesives indicated successful results on dentin, but their bond strength on enamel has been compromised. Different methods have been introduced for bond strength improvement. One of these is different application methods of adhesive systems. Therefore, this study aimed to evaluate the influence of two different application methods of self-etch adhesive system on shear bond strength to enamel. Methods and Materials: In this In-Vitro study, 60 permenant bovine incisors were divided into three experimental groups randomly. At control group the Silorane-based primer was used as manufactururers instructions. At the second group, the enamel surface was pre-etched by phosphoric acid (15 seconds) before primer application and at the third group active primer agitation was utilized. After application and shaping composite resin on the surfaces, samples were stored at 37C for 24 hours and thermocycled. Then the shear bond strength (SBS) of samples was measured and collected data was analyzed by one-way analysis of variance (ANOVA). The Scheffe post-hoc test was used for comparison between groups, the P<0.05 was considered as statistically significant in this study. Results: The shear bond strength to enamel at first, second and third groups was 77.06 19.72, 178.10 50.83, and 57.84 21.32, respectively. ANOVA analysis of variance indicated that there is significant difference between groups (P=0.000). Scheffe post-hoc analysis revealed that the SBS of tested groups was higher at second group (pre-etching by phosphorc acid) compared to two other groups (P=0.000). Conclusions: based on the limitations of this study, shear bond strength to enamel is increased in application of phosphoric acid pre-etching before primer application.