A Comparative in vitro Evaluation of Composite Resin Adhesives, Resin-modified Glass-ionomer Adhesive System and Cyanoacrylate Adhesives

Objective: This study evaluated the shear-peel bond strength of 4 commercial adhesive agents compared them to two conventional resin bonding composites. Methods: Eighty sound human extracted premolars were randomly divided into 8 test groups of 10 teeth each. The roots of each tooth were notched and embedded into individual lugs with self-curing acrylic before the bonding procedures. Premolar 80 mesh orthodontic brackets were bonded to the tooth specimen in each group according to the manufacture's instructions. Additionally, the teeth of test groups 7 and 8 were treated with one and two coats of selfetching primer for 3-5 seconds each coats. All the teeth were bench cured for 15 minutes to ensure complete curing, then stored in deionized water at 370C for 24 hours. An Instron machine (Instron Corp, Canton Ma) was used to determine the shear-peel bond strength in megapascals. The residual adhesive on the enamel surface was evaluated using the Adhesive Remnant Index. Comparisons were made (ANOVA and the Tukey method) between each group. Significance was predetermined at p<.05. Results: The results indicated that the Affirm self-cure, resin modified glass-ionomer cement (x = 16.22 + 3.44) showed higher shear bond strength than conventional resin (x = 11.72 + 2.52) and other bracket bonding adhesives. The application of three coats of self-etching primer resulted in increased in shear bond strength (x = 10.82 + 3.74) compared with two coats of self-etching primer (x = 7.77 + 2.26) and a single coat of self-etching primer (x = 6.69 + 1.43).Conclusion: (1)The shear-peel bond strength of resin-modified glass ionomer adhesive is significantly greater than the conventional resin adhesives and cyanoacrylate adhesives. (2) Multiple application of self-etching primer/Transbond XT compared to single application of self-etching primer/Transbond XT demonstrated greater shear bond strength values.