Comparison of facial soft tissue changes after treatment with 3 different functional appliances

Abstract

This study aimed to evaluate the effects of 3 different fixed or removable functional appliances on the soft tissue changes in patients with Class II Division 1 malocclusion using 3-dimensional images. A total of 60 patients with Class II Division 1 malocclusion (38 girls and 22 boys; mean age, 12.35±1.01years) were treated with 3 different functional appliances, namely, Twin-block (TB) (group TB, n=20), mono-block (MB) (group MB, n=20), or Herbst (H) (group H, n=20) for 9.55±1.46months. Three-dimensional photographs of each patient were taken at the baseline and the end of the therapy with a 3dMD Face system (3dMD, Atlanta, Ga). Statistical analyses were performed using the dependent samples t test, 1-way analysis of variance, Kruskal-Wallis, Mann-Whitney U, and Wilcoxon signed rank tests. No statistically significant differences were detected for soft tissue changes except for the lower facial width found, at least in group H (P<0.05). Volumetric differences in the mandible were similar between the groups (P>0.05). A statistically significant decrease in total facial height and an increase in convexity angle and facial depth were detected in all groups after treatment compared with the baseline (P<0.05). The upper and lower facial height, lower lip height, and nasal width were statistically significantly increased in the TB and MB groups after treatment compared with the baseline (P<0.05) and similar to those in group H (P>0.05). TB, MB, and H appliances may promote the facial soft tissue profile, including volumetric improvement, in the mandibular region.