Canine retraction and anchorage loss using self-ligating and conventional brackets with sliding mechanics: A split-mouth clinical study

Abstract

OBJECTIVE: Appliance biocompatibility, orthodontic treatment efficiency and patient convenience are the major issues confronting contemporary orthodontic practice. Very few studies have been published till date regarding the efficiency of self-ligating brackets as against conventional brackets. Hence, the present study was planned to compare the rate of canine retraction between self-ligating and conventional brackets and to determine the amount of anchorage loss during canine retraction. METHODS: The present clinical study was designed as a prospective, observational study comprising of 25 patients requiring first premolar extraction as a part of orthodontic treatment. Self-ligating and conventional brackets were bonded using a split-mouth study design randomly. Retraction of canines was done with 150 grams of force using Dontrix gauge with E-chains. The study was conducted in relation to upper arch only, while the rate of retraction was evaluated every 4 weeks for 3 months. Average rates of retraction in 3 months were calculated. For anchorage loss, an acrylic guide plug was used in mid-treatment cast (T0) and after 3 months of retraction (T3). The statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, IL, USA). Independent t-test was used to compare the means of the two variables studied, while Pearson's correlation coefficient was used to evaluate the correlation between the variables studied in the groups included. P < .05 was considered statistically significant. RESULTS: The correlation coefficient between the average rate of canine retraction with self-ligating brackets vs. conventional brackets over a period of 3 months came out to be 0.6434, while on comparing the data in terms of anchorage loss over a period of 3 months, the respective correlation coefficient value was found to be 0.6659 with the results being statistically highly significant in either case (P < .001). CONCLUSIONS: Self-ligating brackets showed double the amount of displacement compared to conventional brackets in some of the cases. Also, chair side time was significantly reduced with self-ligating brackets as against conventional brackets.

Keywords

• anchorage loss
• canine retraction
• conventional brackets
• e-chain
• self-ligating brackets