Comparison of Microleakage under Rebonded Stainless Steel Orthodontic Brackets Using Two Methods of Adhesive Removal: Sandblast and Laser

Objectives: Debonding is a common occurrence in orthodontic treatment and a con- siderable number of orthodontists prefer to rebond the detached brackets because of economic issues. The aim of this study was to compare the microleakage beneath re- bonded stainless steel brackets using two methods of adhesive removal namely sandblast and laser. Materials and Methods: Sixty human premolar teeth were randomly divided into three groups. Following bonding the brackets, group 1 served as the control group. Brackets in groups 2 and 3 were debonded, and adhesive removal from the bracket bases was done by means of sandblasting and Er-YAG laser, respectively. After re- bonding, teeth in each group were stained with 2% methylene blue for 24 hours, sec- tioned and examined under a stereomicroscope. Marginal microleakage at the adhe- sive-enamel and bracket-adhesive interfaces in the occlusal and gingival margins was determined. Statistical analysis was done using the Kruskal-Wallis test. Results: Comparison of the microleakage scores among the three groups revealed no statistically significant difference (P > 0.05). At the enamel-adhesive interface, the gingival margins in all groups showed higher microleakage while in the adhesive- bracket interface, the occlusal margin exhibited greater microleakage. Conclusion: Er YAG laser irradiation and sandblasting for adhesive removal from the debonded brackets yielded clinically acceptable microleakage scores.