Comparison of Microleakage in Metal Brackets Bonded using Self-etching Adhesive with and without Fluoride Release: An in vitro Study

Abstract

Objective: To evaluate and compare the extent of microleakage directly beneath the metal brackets bonded to extracted premolar teeth using self-etching-primers (SEP) with and without fluoride release and conventional acid etching using 37% phosphoric acid. Materials and methods: Sixty extracted premolars were segregated into three groups. Forty teeth were etched with SEP, out of which 20 were etched with fluoride containing SEP (Xeno 3) and 20 with nonfluoride SEP (easy one). These two groups were compared with a control group etched with conventional 37% phosphoric acid. 3M Unitek brackets were bonded following manufacturer's instructions and specimens were kept in distilled water and thereafter subjected to thermal cycling. The specimens were stained with 0.5% basic fuschin for 24 hours, sectioned and photographed under a microscope. Microleakage was observed in all the groups and was scored with regard to the adhesive -tooth interface in both the gingival and incisal margins. Statistical analysis was accomplished by Kruskal-Wallis test and statistical significance set at p < 0.05. Results: Even though microleakage was observed in all the groups, the results indicate that these are not clinically significant (p < 0.132). Brackets bonded with SEP without fluoride released showed more microleakage than brackets bonded with SEP with fluoride release. Conclusion: Addition of fluoride in the orthodontic adhesive system reduces the severity of microleakage but does not eliminate its incidence totally.