Acid conditioning combined with single-component and two-component dentin bonding agents

Objective: The purpose of the present study was to compare ethylenediaminet etraacetic acid conditioning and phosphoric acid conditioning of dentin in combination with two principally different commercial dentin bonding system s. Method and materials: Twenty-one extracted human third molars were used. All teeth were caries free, and no teeth were root filled. In total, 29 pa irs of dentin surfaces were obtained from 21 teeth. One dentin surface in e ach pair was etched with a 32% phosphoric acid gel for 15 seconds, and the opposite surface was etched with a 24% ethylenediaminetetraacetic acid gel for 3 minutes. One experimental group of 15 dentin surface pairs was subseq uently bonded with All-Bond 2, a two-component system, and the other group of 14 pairs was bonded with Prime & Bond NIT, a one-bottle adhesive. A flow able resin composite was inserted in the experimental cavity and light cure d. Shear bond strength testing was performed according to the protocol of t he International Organization for Standardization. Results: The combination of conditioning with ethylenedlaminetetraacetic acid and bonding with All- Bond 2 was significantly better than all other combinations, providing a sh ear bond strength that was 61% to 123% greater. Conclusion: Use of ethylene diaminetetraacetic acid in combination with All-Bond 2 resulted in a signif icantly greater bond strength to dentin than did conventional acid etching.