Evaluation of enamel roughness after ceramic bracket debonding and clean-up with different methods

Aim: This study evaluated the surface roughness (Ra) and the topography (scanning electron microscopy) of the dental enamel after use of different methods for removal of residual resin after debonding of orthodontic brackets.
Methods: Nine roughness measurements in three directions were made on enamel surface of 60 human premolars before bracket bonding (Ra initial). Ceramic brackets were bonded with Transbond XT and stored for 24 h/37°C before debonding with pliers. The specimens were divided in five groups according to the method used for removal of residual resin: control (C); carbide bur at slow-speed (CL); carbide bur at high speed (CH); Shofu tip at low speed (SB); Shofu tip at high speed (HB); debonding pliers (ZP). Nine final surface roughness measurements (Ra final) were made and one specimen of each group was observed by SEM. The data were analyzed statistically by ANOVA, Tukey′s test and paired t test (p<.05).
Results: Ra final of SB was significantly higher than C, CL, CH, and ZP groups. The t-test showed that the Ra final was significantly higher than Ra initial for SB and CL.
Conclusions: The method used for removal of residual resin influenced the roughness of the enamel. Carbide bur at high speed presented the best results and Shofu at low speed presented the worst results.