Comparison of Canine & Molar Rotation Caused by NiTi Coil Spring and Elastomeric Chain in Treatment of Class II Division 1 Extraction Cases in a Tertiary Hospital

Abstract

Introduction: Understanding the effects of NiTi coil springs and elastomeric power chain methods in canine retraction and comparing their outcomes can help improve orthodontic treatment results by increasing the efficiency of the treatment.
Materials and methods: This quasi-experimental study was carried out among 20 participants, including both males and females, aged between 13 to 25 years, with Class II division 1 malocclusion requiring upper first premolar extractions, who were selected by purposive sampling technique. After obtaining written consent, a study model was obtained before initiation and after completion of space closure. During canine retraction, a power chain was placed at one side while a coil spring was placed in other side of upper jaw of each participant. Elastomeric chain was changed after every 3 weeks whereas the NiTi coil was only changed if it was broken. After completion, data were recorded and analyzed through data management descriptive statistics including mean and standard deviation (SD) for all measurements. Paired t-tests were used to assess the data after a normality test was completed. A p-value<0.05 was considered statistically significant.
Results: This current study revealed that NiTi coil springs showed higher mean rotation of canine (5.1°) and molar (1.1°) than the power chain group. However, the p-values for all comparisons—canine rotation (p=0.077) and molar rotation (p=0.805)—indicated that the differences were not statistically significant. The results also showed no significant differences between the age groups or genders.
Conclusion: This study demonstrates that NiTi coils had slightly more canine & molar rotation than power chain group. Although the two methods did not significantly differ in their treatment effects between the age groups or genders.

J. Contemp. Dent. Sci. 2026;14(2): 17-21