Evaluation of dental enamel after debonding of sapphire brackets and removal of orthodontic adhesive remnants.

Abstract

<h4>Introduction</h4>Iatrogenic effects on dental enamel are common during the debonding of aesthetic brackets and the removal of residual adhesive.<h4>Objective</h4>To evaluate the impact of these procedures on enamel integrity via advanced imaging techniques.<h4>Methods</h4>Human premolar crowns (n=60) were bonded with sapphire brackets and debonded using 346R pliers (G1, n=30) and 346B pliers (G2, n=30). Adhesive removal was performed with a multilaminated zirconia bur (EG1, n=30) and a multilaminated carbide bur (EG2, n=30). Surface roughness was assessed via optical profilometry; enamel loss and microcracks, via microcomputed tomography; and the adhesive remnant index (ARI), via optical coherence tomography. After normality and homogeneity tests, Mann-Whitney and Wilcoxon tests were applied (p<0.05).<h4>Results</h4>The 346R plier presented a slightly higher ARI than the 346B plier. Both removal methods significantly increased surface roughness, without causing enamel microcracks. The zirconia bur demonstrated greater adhesive removal efficiency but was associated with increased enamel loss.<h4>Conclusions</h4>Variations in the shape and force vector of the pliers did not affect enamel outcomes. The zirconia bur system at low speed was more efficient at removing orthodontic adhesive remnants, resulting in a lower final ARI on the enamel surface, and none of the procedures caused enamel microcracks, as evaluated by microcomputed tomography.