Abstract: Objective: To evaluate the effect of Damon self-ligating and 3M smartclip bracket systems on buccal corridor area and maxillary arch width. Methods: A retrospective sample of consecutively treated patients using either 3M or Damon self-ligating brackets was analyzed to determine any differences in buccal corridor area both within and between groups. Pretreatment and post-treatment standardized frontal posed smile photographs and upper dental casts were taken. Results: There were no significant differences in any buccal corridor area either within or between the Damon and 3M smartclip system (P＞0.05). The inter second premolar and first molar width had significant changes in Damon system after treatment, and the changes had significant difference between two groups (P＜0.05). Conclusion: After treatment, arch width increases more in patients treated by Damon self-ligating brackets than 3M smartclip. There is no significant difference in buccal corridor width between patients treated with the Damon and 3M smartclip system.

Key words: Damon Q, Buccal corridors, Maxillary arch width