To evaluate and compare the microtensile bond strength of dentine with the use of two-step and one-step adhesives: An ex vivo study

Introduction: In the evolving world of adhesive dentistry, there has always been controversy regarding the adhesive system to be used for superior clinical performance, and clinicians often find themselves in a dilemma with so many products on the market. It, therefore, becomes necessary to know the various properties of different adhesive systems and their comparative analysis. Materials and Methods: Thirty, intact, non-carious and unrestored human mandibular premolars, which were extracted for orthodontic purposes were taken for the study. Teeth were divided into two groups A and B having 15 teeth in each group. The inclusion criteria were that the teeth should be non-carious, unrestored and should have been extracted for orthodontic purposes. Excluded teeth were those with caries, restorations, attrition, cracks and developmental defects. The teeth were embedded in resin, occlusal enamel was removed and the teeth were restored with composite resin using two different approaches for bonding. Teeth of Group A were bonded using single bond and teeth of Group B were bonded using Clearfil S3 Bond and were then sectioned to produce beams with an approximate cross-sectional area of 4 mm × 4 mm. These sections were mounted to a custom acrylic jig and subjected to microtensile bond strength testing using a universal testing machine with a cross head speed of 1 mm/min and stressed to de-bonding of the composite resin from the tooth. Results: Data were subjected to statistical analysis and evaluated using the analysis of variance test and Tukey's test which showed that single bond or two-step adhesive showed higher microtensile bond strength to dentine. Conclusion: The two-step single bond performed better than the one-step Clearfil S3, but the result was statistically non-significant.