Shear bond strength of different retainer wires and bonding adhesives in consideration of the pretreatment process

Introduction: We aimed to compare the shear bond strength (SBS) of three different retainer wires and three different bonding adhesives in consideration of the pretreatment process of enamel surface sandblasting. Methods: 400 extracted bovine incisors were divided into 10 groups of 20 paired specimens each. 10 specimens of each group were pretreated by enamel sandblasting. The retainer wires Bond-A-Braid (TM), GAC-Wildcat (R)-Twistflex and everStick (R) ORTHO were bonded to the teeth with the adhesives Transbond (TM)-LR, Tetric-EvoFlow (TM) and Stick (R) FLOW and then debonded measuring the SBS. Results: While sandblasting generally increased SBS for all tested combinations, the retainer wires bonded with Transbond (TM)-LR showed the highest SBS both with and without prior sandblasting. Significantly lower SBS were found for Tetric-EvoFlow (TM) that were comparable to those for everStick (R) ORTHO. Conclusions: Pretreatment of enamel surfaces by sandblasting increased the SBS of all retainer-wires. Transbond (TM)-LR showed the best results compared to Tetric-EvoFlow (TM) and everStick (R) ORTHO, while all combinations used provided sufficient bonding strengths for clinical use.