Abstract
AIMS:To evaluate and compare the microleakage occlusally and gingivally under bracket-compositeinterface of sapphire ceramic, stainless steel and composite orthodontic brackets bonded with twodifferent generations of orthodontic adhesives.MATERIALS AND METHODS: Seventy-two freshlyextracted premolars were utilized in this study. Three types of orthodontic brackets were used asfollows: sapphire ceramic, composite and stainless steel. The samples were divided into two maingroups of 36 samples; one group was bonded with Resilience® adhesive, while the other was bondedwith Biofix adhesive. Each group was further subdivided into three subgroups of 12 samples accordingto bracket types. After photopolymerization, the samples were thermocycled. Samples were sealed withnail varnish, stained with 2% methylene blue dye then sectioned occlusogingivally, examined under astereomicroscope and measured for microleakage at the bracket-adhesive interface from both occlusaland gingival margins, evaluated statistically with t- tests at p≤0.05 levels of significance. RESULTS:All groups showed various degrees of microleakage, however, no significant differences either betweenthe two adhesives or among the three bracket types were recorded. Microleakage beneath sapphirebrackets was significantly higher under the Biofix adhesive at the gingival side.CONCLUSION: Nosignificant differences were recorded between the occlusal and gingival sites in all of the studygroups.However, the 5th generation adhesive showed higher microleakage with significant differenceunder sapphire ceramic brackets at the gingival margin.
