Effect of fluoride-releasing light-cured resin on shear bond strength of orthodontic brackets.

INTRODUCTION

The aim of this study was to analyze the effect of an enamel-protective resin on the shear bond strength (SBS) of orthodontic brackets bonded with self-etching primer.

METHODS

Eighty extracted premolars were randomly divided into 4 groups of 20, and metal brackets were bonded. Group 1 specimens were bonded with Transbond Plus self-etching primer (3M Unitek, Monrovia, Calif) and no fluoride resin; in group 2, a fluoride-releasing resin (Ortho-Coat, Pulpdent, Watertown, Mass) was used with the Transbond Plus self-etching primer; group 3 teeth were bonded with a new antimicrobial self-etching primer (Clearfil Protect Bond, Kuraray Medical, Osaka, Japan) with no fluoride resin; and the same protocol was used in group 4 with an application of Ortho-Coat. A universal testing machine was used to determine the SBS, and the adhesive remaining after debonding was assessed.

RESULTS

There was no difference in SBS whether fluoride-releasing resin was used. Groups 3 and 4 had higher SBS values than the other groups (P <0.001). The Kruskal-Wallis test showed no significant differences in the adhesive remnant index (chi-square = 0.019, P = 0.990).

CONCLUSIONS

The application of enamel-protective resin did not affect the bond strength of orthodontic brackets to enamel with self-etching primer systems.