Rate of Canine Retraction and Anchorage Loss – In Smart Clip versus Conventional Brackets (An in-vivo study)


  • Command Military Dental Centre, Jaipur, Cl Spl (Orthodontics), India


Background: To analyse the rate of maxillary canine retraction and anchorage loss in Smart Clip Self Ligating (SCSL) and Conventional (CV) brackets. Materials and Methods: Forty four subjects were selected for the study requiring sectional maxillary canine retraction in first premolar extraction space during orthodontic treatment. The self ligating bracket (Smart Clip, 3M Unitek) on maxillary canine was compared to CV bracket (APC Victory series) on the contralateral side in a random split-mouth study design. Sectional canine retraction was done with a NiTi coil spring (150 gms force, 9 mm) on 0.016 × 0.022" slot stainless steel wire. Results: The mean rate of distal movement of maxillary canine for the conventional (CV) bracket per 28 days was 1.048 mm and 1.027 mm for smart clip self ligating bracket (SCSL). Anchorage loss in molar was 0.586 mm and 0.652 mm for CV and SCSL bracket respectively. Conclusion: The rate of canine retraction for conventional bracket was faster than self ligating bracket, but not statistically significant (p>0.05). Comparatively, no major difference was found in terms of molar anchor loss between both bracket types. Therefore, this study indicates that conventional brackets are equally efficient as compared to self ligating brackets for segmental canine retraction mechanics.


APC, Canine retraction, Self-ligating

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