Changes in soft tissue facial profile of craniofacial microsomia patients: geometric morphometrics

To analyze changes in the soft tissue profile associated with an inverted L osteotomy, preoperative, early postoperative, and late postoperative lateral cephalographs of 13 children with craniofacial microsomia (mean age 9 +/- 2 years) were scanned, and 11 soft tissue landmarks were digitized (digitization errors insignificant; P > 0.05). Cephalometry, Euclidean distance matrix analysis (EDMA), and thin-plate spline (TPS) analysis were carried out on the mean soft tissue landmark configurations. Cephalometry indicated that there were very few statistically significant differences in mean measurements pre- and postoperatively. In contrast, EDMA determined that there were significant differences (P < 0.05) between mean preoperative, early postoperative, and late postoperative soft tissue configurations, particularly in the labiomental region. Transformation grids obtained from TPS analysis indicated clockwise rotation of the soft tissue configurations with anteroinferior elongation in the labiomental region. Geometric morphometrics indicated that the soft tissue lower facial height increased secondary to the associated underlying skeletal change, improving the profile of patients treated with an inverted L osteotomy of the mandible for the correction of craniofacial microsomia.