Shear bond strength of orthodontic brackets with 3 self-etch adhesives

Introduction: The purpose of this study was to compare shear bond strength and mode of failure of brackets bonded with 3 self-etching products. Methods: The products tested were (1) a recently developed, modified self-etching, 1-step adhesive system (Adper Prompt L-Pop Self Etch Adhesive, 3M, St Paul, Minn); (2) a new fluoride-releasing, antibacterial, self-etching adhesive system (Clearfil Protect Bond, Kuraray, Osaka, Japan); and (3) a fluoride-releasing, self-etching adhesive system (Transbond Plus Self Etching Primer, 3M). Thirty-six defect-free premolars were randomly divided into 3 groups (n = 12 each), and metal brackets were bonded according to the manufacturer's instructions. Brackets were debonded in shear on a universal testing machine with a crosshead speed of 1 mm per minute. Results: One-way ANOVA showed a statistically significant (P < .001) difference between groups. Group 2 had the highest shear bond strength. The difference between groups 1 and 3 was not statistically significant. The Kruskal-Wallis test showed no significant differences in the ARI scores (P = .595; P < .05). Conclusions: The fluoride-releasing, antibacterial, self-etching adhesive system, Clearfil Protect Bond, produced greater shear bond strength than the other 2 products tested and could be considered for clinical use.