Shear bond strength of self-etch and total-etch adhesives to bovine enamel and dentin

Abstract

Purpose: To evaluate the shear bond strength of a self-etch adhesive and an etch-and-rinse adhesive when bonded to bovine enamel and dentin. Methods: The labial surfaces of 28 bovine mandibular incisors were wet ground to achieve a flat enamel or dentin surface. A 1-step self-etch adhesive and a 3-step etch-and-rinse adhesive were bonded to enamel or dentin according to the manufacturer’s instructions (Adper Easy One and Adper Scotchbond, respectively). A composite resin cylinder (Filtek Z350 XT) was built upon the adhesive layer using a silicon mold (2 mm in diameter  3 mm high). The specimens were stored in 37°-C distilled water for 24 h. The bond strength was measured by a universal testing machine at a crosshead speed of 1.0 mm/min. Student’s t-test was used to compare bond strength values between adhesives at the 95% confidence level. Results: For the enamel specimens, Adper Scotchbond had significantly higher values of bond strength than Adper Easy One (P = 0.007). For the dentin specimens, there were no statistically significant differences between adhesives (P = 0.12). Conclusion: Adper Easy One showed lower shear bond strength than Adper Scotchbond on enamel. For dentin, Adper Easy One showed bond strength similar to Adper Scotchbond.