Does Preoperative Supratip Soft-Tissue Thickness Predict Early Postoperative Edema Following Orthognathic Surgery? A Prospective Study Using Ultrasonography and 3-Dimensional Stereophotogrammetry

Background: Postoperative facial edema remains one of the most common early sequelae of orthognathic surgery, yet the contribution of intrinsic soft-tissue characteristics to postoperative swelling remains poorly understood. To our knowledge, this is the first prospective study to evaluate whether preoperative supratip soft-tissue thickness independently predicts early postoperative facial edema using high-resolution ultrasonography and longitudinal 3-dimensional stereophotogrammetry. Purpose: To determine the independent effects of preoperative supratip soft-tissue thickness and surgical technique on early postoperative facial edema following orthognathic surgery. Study Design, Setting, and Sample: This prospective, randomized, double-blind clinical study included 48 patients undergoing bimaxillary orthognathic surgery at a single tertiary referral center. Patients underwent either subspinal Le Fort I osteotomy (SLFI; n=22) or conventional Le Fort I osteotomy (CLFI; n=26). Preoperative supratip soft-tissue thickness was measured using high-resolution ultrasonography, whereas postoperative facial edema was serially quantified by 3-dimensional stereophotogrammetry. Multivariable linear regression with heteroscedasticity-consistent robust standard errors was performed to identify independent predictors of postoperative edema. Results: Patients treated with the SLFI exhibited significantly less postoperative edema than those treated with the CLFI throughout the early postoperative period, with the greatest between-group difference observed at peak swelling. Multivariable regression identified surgical technique as the sole independent predictor of postoperative edema. In contrast, preoperative supratip soft-tissue thickness was not independently associated with postoperative swelling after adjustment for age, sex, and body mass index and showed no significant predictive value at any postoperative time point. Conclusions: Despite accurate preoperative quantification, supratip soft-tissue thickness was not an independent predictor of early postoperative facial edema. In contrast, surgical technique emerged as the principal independent predictor of postoperative swelling, suggesting that preservation-oriented approaches such as subspinal Le Fort I osteotomy may facilitate improved early soft-tissue recovery.