Effects of application time and agitation for bonding orthodontic brackets with two self-etching primer systems

The purpose of this study was to evaluate the shear bond strength, adhesive remnant index (ARI) and etching effect of two self-etching systems (Transbond Plus, Beauty Ortho Bond) at different application times (3, 10, 30 seconds) with and without agitation. Share bond strengths were examined and the ARI score was estimated (n=15). Enamel surfaces after priming were examined by SEM. Increasing application time and applying agitation of self-etching primers produced slightly increased etching efficacy. Increasing application time did not significantly increase the shear bond strength. Also, agitation did not significantly increase the shear bond strength except for specimen bonded with the Beauty Ortho Bond with 10 seconds application time. No significant difference was found in bond-failure sites among 10 groups. Although increasing application time and applying agitation of both self-etching primers did not affect the shear bond strength, increasing application time in indirect bonding technique should not cause remarkable adverse effect.