Comparison of tensile bond strength of new and rebonded Symetri Clear™ ceramic brackets with Transbond™ XT or BluGloo™, with or without surface treatment: An in vitro study.

OBJECTIVES

This study sought to determine the bond strength of the Symetri Clear™ bracket after rebonding (reused) for a second and third time.

MATERIALS AND METHODS

Symetri Clear™ mandibular incisor brackets were bonded to bovine incisors and divided into six experimental groups. Two groups underwent tensile bond strength testing, and the remaining four groups were debonded using the manufacturer's recommended plier. Two groups were rebonded twice following surface preparation with Ortho SoloTM and two groups were rebonded twice without surface preparation. The rebonded brackets also underwent tensile bond strength testing after each rebonding event as well as receiving an Adhesive Remnant Index score.

RESULTS

One-way ANOVA found a statistically significant difference in bond strength among the six groups (P<0.0001). Tukey's Studentized Range (HSD, honestly significant difference) Test found significant differences in tensile bond strength of groups which did not undergo surface preparation prior to rebonding. One-way ANOVA found a P-value of 0.2563 and thus no significant difference in ARI among the different groups.

CONCLUSIONS

There was no significant difference in the tensile bond strength of Symetri ClearTM brackets initially bonded with either Transbond™ XT or BluGloo™ and no significant difference between the initial tensile bond strength and the first or second rebond tensile bond strength. Rebonding Symetri Clear™ brackets without surface treatment did show significantly reduced tensile bond strength.