Computerized occlusal analysis of two different removable retainers used during retention phase- A Randomized controlled trial

ABSTRACT Aim: To evaluate and compare occlusal contact force distribution, occlusion time and disclusion time following wear of Begg’s wrap around retainer and Vacuum formed retainer after completion of orthodontic treatment using a T-scan III. Materials and Methods: Twenty subjects after completion of active orthodontic treatment were randomly allocated into two groups, Group I – Begg’s wrap-around retainer (n-10) and Group II–vacuum formed retainer (n-10) one patient was lost to follow up in each group and the final sample size assessed at T1 in each group was 9. T-scan III was used at two-time intervals, T0 – first scan taken immediately after debonding and T1 – taken during retention any time between 10 and 12 months. Comparison of parameters within the groups was done using paired t-test and comparison between the groups was done using independent t-test. Results: No statistically significant difference in the distribution of occlusal contact forces was noted in both groups at T0 and T1 (p value<0.05). Disclusion time reduced in both groups at T1 but a statistically significant reduction in the disclusion time of left lateral excursive movement and protrusive movements (p value<0.05) was noted (T0-T1) in Group I. Statistically significant increase in the occlusion time was noted in Group II (T0-T1) at T1 between the two groups. Conclusion: No differences in occlusal contact force distribution was noted within and between the two groups. Disclusion time reduced in subjects on Begg’s wrap around retainers indicating favourable muscle activity and Occlusion time increased in subjects on vacuum formed retainers.