Brackets bonding failure after in-office bleaching in vivo


The aim of this in vivo study was to determine the effect of high concentration35% hydrogen peroxide bleaching agent on metallic brackets bonding failure. Fortypatients who received first orthodontic treatment phase, were included in this study.A split mouth technique was used; one arch exposed to in-office bleaching gelcontaining 35% hydrogen peroxide for 30 minutes, while the unbleached arch servedas the control. Patients were divided into four groups: First two groups, the bracketsbonded 48 hours after bleaching while the third and fourth groups, brackets bonded 3weeks after bleaching. The bracket failure was computed using independent T-test.The higher bracket failure occurs in mandibular bleached group 48 hours beforebonding (18.33%) while the lowest bracket failure occurs in unbleached groups (1.67%). Significant differences were showed in bracket failure between the mandibularbleached teeth 3 weeks before bonding and those 48 hours before bonding. AdhesiveRemnant Index scores revealed that the majority of failure in bleached teeth occurredin the enamel/resin interface. The 48 hours bleached teeth before bondingsignificantly had a high bracket failure. We should increase the time lapse betweenbleaching and bonding procedure more than 3 weeks to improve the bracket bondingstrength.