This study was performed to evaluate the effects of bonded labial appliances on lip and perioral soft tissue using three-dimensional images acquired by a laser scanner and to improve the clinician’s ability to predict the three-dimensional soft tissue changes following debonding.
Three-dimensional facial scans were taken after debonding (T1) and immediately after debonding (T2) from 53 patients (19 males and 34 females) and follow-up scans were taken 3 months after debonding (T3) from 31 patients (13 males and 18 females). To compare the scans taken at different time periods, superimposition was performed and for a quantitative analysis, shell-to-shell deviation was used.
Results: The results obtained were as follows.
1. Shell-to-shell deviation map showing warm colors in lip and perioral soft tissue represented the retrusion of soft tissue after bracket removal.
2. Soft tissue changes in all landmarks were statistically significant immediately after debonding (T1-T2) and after retention period (T1-T3) (P < .01).
3. In regard to gender, lower lips of females were more retruded than those of the males during the post-debonding period (P < .05).
4. Comparisons between time intervals suggested that the vermilion borders are significantly retruded more during the post-debonding period than other perioral areas (P < .05).
5. Strong positive correlation was found in the lower lip between the changes immediately after debonding (T1-T2) and after retention period (T1-T3) (P < .01).
Conclusion: Evaluation with three-dimensional laser scanning showed significant differences in lip and perioral soft tissue following debonding of labial appliances.