Shear bond strength of brackets bonded with different self etching primers

Yang, Jin Young; Kim, Min Ji; Lim, Yong Kyu; Lee, Dong Yul

Abstract

OBJECTIVE
The purpose of this study was to evaluate the clinical usefulness of 4 self etching primers by measuring the shear bond strength of orthodontic brackets and examining the failure pattern of bracket-tooth interfaces.
METHODS
Seventy-five, defect-free, premolars were randomly assigned into five groups: control group (37% phosphoric acid + Transbond XT primer) and self etching primer treated groups (Transbond Plus self etching primer, Unifil bond, Clearfil SE bond, and Adhese). The shear bond strength was measured with a universal testing machine and the amount of residual adhesive remaining on the brackets after debonding was assessed by the adhesive remnant index (ARI).
RESULTS
The results showed that the groups conditioned with self etching primer had significantly lower shear bond strength than the control group (p < 0.05), although clinically acceptable. However, there were no significant differences in shear bond strength among the self etching primer groups (p > 0.05). Evaluation of the ARI scores indicated there was less resin remnant on the teeth in the groups conditioned with self etching primers, although not statistically significant.
CONCLUSION
The results of this study suggest that all four of the self etching primers have shown acceptable bond strength for clinical use.