Bond strength of adhesive systems to sound and demineralized dentin treated with bioactive glass ceramic suspension

Objective The objective of this study was to evaluate the effect of a Biosilicate (R), associated with dentin adhesive system, on microtensile bond strength (mu TBS) to sound and demineralized dentin. Materials and methods Eighty sound-extracted molars had their middle occlusal dentin exposed. In forty teeth, dentin was artificially demineralized (pH cycling). Sound and demineralized dentin teeth were separated into four groups (n = 10), according to the substrate treatment before restoration: Group 1-total-etching adhesive Adper TM Single bond 2 (ASB) + Biosilicate (R), Group 2-ASB (without Biosilicate (R)), Group 3-AdheSE self-etching adhesive system (AdSE) + Biosilicate (R), and Group 4-AdSE (without Biosilicate (R)). Each tooth was restored with a hybrid composite and stored in water at 37 degrees C for 6 months. After water aging, teeth were cut in sticks (approximate to 1 mm(2) cross-sectional area) and all samples were submitted to mu TBS test. The fracture modes of the samples were analyzed by stereomicroscopy. The representatively fractured samples were observed by scanning electron microscopy. Representative samples of each group were analyzed on energy dispersive X-ray spectrometry (EDX). The mu TBS and Ca-P ratio values were analyzed by 2-way ANOVA, Bonferroni, and Tukey test, respectively, p < .05. Results ASB + Biosilicate (R) presented the highest mu TBS values (p < .05), and lowest mu TBS values (p < .05) were found in AdSE Group. There was no statistical difference (p < .05) on mu TBS when substrates were compared, except for Group 2. The fracture pattern analysis showed prevalence of adhesive fractures in all groups. Conclusion Biosilicate (R) enhanced bond strength of self-etching and etch-and-rinse adhesives to sound and demineralized dentin.