A New Solvent-free One-Step Self-Etch Adhesive: Bond Strength to Tooth Structures

Abstract

In recent years some new solvent-free dental adhesives have been marketed. This study evaluated bonding effectiveness of a new one-step solvent-free self-etch adhesive in comparison with a common two-step self-etch adhesive used as gold standard. Flat enamel and dentin surfaces were prepared on 60 incisors using silicon carbide papers. Clearfil SE Bond (CSEB) and Bond 1SF (B1SF) adhesives were applied on enamel/dentin surfaces in four groups (n = 15): (1) Enamel surface and CSEB, (2) dentin surface and CSEB, (3) enamel surface and B1SF, (4) dentin surface and B1SF. Composite resin buildups were carried out using Z100 composite resin. All the specimens were stored for 24 hours at 37°C and 100% relative humidity. After 500 rounds of thermocycling, shear bond strength (SBS) test was performed using a universal testing machine at 1 mm/min crosshead speed. Data were analyzed with one-way ANOVA and a post hoc Tukey test (α = 0.05). In each experimental group, two additional specimens were prepared for scanning electron microscopy evaluation. Significant differences were observed between the study groups (p < 0.001). The highest enamel/dentin bond strengths were recorded in group 1 (CSEB) (p < 0.001). The SBS of the two-step self-etch adhesive to enamel and dentin was significantly higher than that of the one-step self-etch adhesive (p < 0.001). There was no significant difference between enamel and dentin SBS with B1SF (p = 0.559). Within the limitations of the present study, when bonded to enamel and dentin the solvent-free adhesive B1SF underperforms as compared to CSEB as the control gold standard.