A prospective optical surface scanning and cephalometric assessment of the effect of functional appliances on the soft tissues

The aim of this study was to evaluate the effect of different functional appliances on the soft tissues as assessed by cephalometry and optical surface scanning. Forty-two patients were randomly allocated to Bass, Twin Block (TB), and Twin Block + Headgear (TB + Hg) groups. Lateral cephalograms and optical surface scans were recorded before and after the 10-month study period. ANOVA was used to test the cephalometric variables for differences at the 5 per cent level. The optical surface scanning and cephalometric results were consistent in the sagittal dimension. In the vertical dimension, however, the optical surface scans consistently recorded a greater increase compared with cephalometric values. No differences were detected with regard to cephalometric values at the 5 per cent level. However, the Bass appliance produced greater forward positioning of soft tissue pogonion as assessed by optical surface scanning.