Evaluation of soft tissue morphologic changes after using the alar base cinch suture in Le Fort I osteotomy in mandibular prognathism with and without asymmetry

PurposeThe purpose of this study was to investigate the effects of alar base cinch suture in Le Fort I osteotomy in mandibular prognathism with and without asymmetry.Material and methodsForty patients who underwent Le Fort I osteotomy were divided into an asymmetry group and a symmetry group (n = 20 each). Computed tomography (CT) was taken in all patients before and 1 year after surgery. The CT-3D volume rendering data with Aquarius Net (TeraRecon, Foster City, CA, USA) was reconstructed and the soft tissue was measured as follows, the distance between the bilateral alar base (Alar base width), the distance between the bilateral alar (Alar width), the angles between the FH plane and the line between the bilateral alar base (Alar base angle), the angle between the FH plane and the line between the bilateral alar (Alar angle), the angle between the FH plane and the line between the bilateral corners of the mouth (Lip angle), and the angle between the perpendicular line to the FH plane and the Philtrum (Philtrum angle).ResultsSignificant differences were observed in the Alar width (P = 0.0448), the Alar angle (P = 0.0044), the Lip angle (P < 0.0001), and the Philtrum angle (P = 0.0057) between before and after surgery in the asymmetry group.ConclusionsThis study suggested that the alar base cinch suture could prevent increases in the alar base width in both groups and help to improve the angle of soft tissue in the asymmetry group, although alar width significantly increases after surgery.