Effect of smear layer thickness and pH of self-adhesive resin cements on the shear bond strength to dentin

摘要

Context: There are concerns in relation to the bonding efficacy of self-adhesive resin cements to dentin covered with the smear layer. Aims: This study aims to evaluate the effect of smear layer thickness and different pH values of self-adhesive resin cements on the shear bond strength to dentin. Materials and Methods: The dentin on the buccal and lingual surfaces of 48 sound human premolars were abraded with 60- and 600-grit silicon carbide papers to achieve thick and thin smear layers, respectively. The samples were divided into three groups (n = 16) based on the cement pH: Rely-X Unicem (RXU) (pH Statistical Analysis: Data were analyzed with two-way ANOVA and post hoc least significant difference tests (P Results: Cement pH had a significant effect on the shear bond strength (P = 0.02); however, the smear layer thickness had no significant effect on the shear bond strength (P > 0.05). The cumulative effect of these variables was not significant, either (P = 0.11). Conclusion: The shear bond strengths of SPC and CSL self-adhesive resin cements were similar and significantly lower than that of RXU. The smear layer thickness was not a determining factor for the shear bond strength value of self-adhesive resin cements.