Evaluation of Microtensile Bond Strength of Universal Self-etch Adhesive System to Wet and Dry Dentin

BACKGROUND: The durability of dentin-resin interfaces with the universal adhesive system is a crucial characteristic with chemical interactions between the exposed collagen and the adhesive monomers, but it is still compromised with wet and dry mode. AIM: The present study evaluated the effect of dentin wetness and solvents containing of one-step self-etch adhesives on the microtensile bond strength (μTBS) of dentin at different storage times. METHODS: Occlusal dentin of 54 extracted human molars was exposed. Each adhesive agent was applied according to manufacturer instructions to wet and dry dentin surfaces. Composite resin was incrementally built up. Bond strengths to dentin were determined using the μTBS test after water storage for 24 h, 1 month, and 6 months. One-way ANOVA was used to compare between more than two non-related samples. The significance level was set at p ≤ 0.05. RESULTS: Dryness of dentin increases the μTBS with solvent-containing adhesives while decrease the μTBS with solvent-free adhesive. There was an increase in microtensile bond strength values in the case of ethanol water-based self-etch adhesive over time. No statistically significant difference was found among different storage times regarding μTBS for solvent-free adhesive, while a statistically significant difference was found among different storage times in μTBS for solvent-containing adhesives. CONCLUSION: Universal adhesive systems improve the durability and stability of dentin bond strength.