ABSTRACT
OBJECTIVE: To compare the mean change of tooth movement in canine retraction between elastic module and Ni Ti coil spring. STUDY DESIGN: Comparative study. PLACE AND DURATION OF STUDY: Orthodontics Department, Armed Forces Institute of Dentistry, Rawalpindi, from May 2015 to January 2016. METHODOLOGY: Thirty-two patients were inducted. After alignment and extraction of maxillary first premolars, canine retraction was started with closed Ni Ti coil spring on one side of the maxillary arch and with active tie back on the other side. The distance between the lateral incisor and the canine was measured on both sides before starting canine retraction. The same measurements were recorded after four weeks of retraction. The difference between pre and post retraction measurements was recorded. The difference in the rate of canine retraction between both modalities was compared using independent sample t-test. RESULTS: The study included 56% females and 43% males. The mean rate of tooth movement in Ni Ti coil group and in the elastomeric module group was 1.1 mm and 0.7 mm in one month, respectively (p=0.05). CONCLUSION: The rate of tooth movement is more rapid with Ni Ti coil spring than with the elastomeric module.
