Cephalometric Evaluation of Soft Tissue Profile Prediction with Video Imaging

Objectives: The purpose of this study was to verify the precision of a video imaging software (Vistadent / GAC Intl.) on the soft tissue profile prediction of patients who underwent different types of orthognatic surgery. Methods: Preoperative and posttreatment lateral cephalograms of 32 patients (24 females and 8 males) were used. Cephalometric profile predictions were obtained from hard tissue movements on the preoperative tracings. Points of prediction's soft tissue line were compared with those of the final tracing on the horizontal and vertical planes. This cephalometric analysis was applied to the total sample and to groups with maxillary impaction or downgraft (V) or without surgeries in the vertical plane (AP). Means, standard deviations, maximum and minimum values were obtained and a Student t test was used to verify significant differences in the total sample and in AP and V groups. Cephalometric errors were cathegorized in a frequency distribution. Results: Cephalometric points of the predictions showed variability in comparison to the posttreatment points, but 60% of errors were less than 2mm and only 17% were greater than 3mm. Nasolabial and mentolabial prediction angles were more acute than those of the final tracings. Conclusions: Statistically significant differences in the cephalometric analysis were more frequently observed on the vertical plane. Factors such as digital software failures, patient individual aspects and radiographic standardization problems may be involved in the computerized prediction process.