Abstract:Objective To explore the trajectory of quality-of-life changes and preoperative predictors in patients undergoing orthognathic surgery for malocclusion.Methods Between September 2022 to July 2024, the 78 patients undergoing orthognathic surgery for malocclusion were selected from the Department of Oral and Maxillofacial Surgery at Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology. The quality-of-life scores were assessed preoperatively and at 1, 3, and 6 months postoperatively to observe their change patterns. A multiple linear regression model was applied to identify preoperative factors influencing postoperative quality-of-life outcomes.Results SF-36 scores for physical functioning, physical role functioning, general health perceptions, and the total SF-36 scores were compared across the preoperative period, and at 1, 3, and 6 months postoperatively, and the one-way ANOVA revealed statistically significant differences across all time points (P < 0.05). At 3 and 6 months postoperatively, SF-36 scores for physical functioning were significantly higher than those at baseline and 1 month postoperatively. SF-36 scores for physical role functioning at 3 and 6 months postoperatively were significantly higher than preoperative values, with scores at 6 months postoperatively also significantly higher than those at 1 month postoperatively. SF-36 scores for general health perceptions at 3 and 6 months postoperatively were significantly higher than both preoperative and 1-month postoperative scores, and the 6-month score was significantly higher than the 1-month score postoperatively. Total SF-36 scores at 3 and 6 months postoperatively were significantly higher than those at baseline and 1 month postoperatively, with the 6-month score also significantly exceeding the 1-month score postoperatively. Additionally, male patients had higher SF-36 scores at 6 months postoperatively compared to female patients. Among patients with Class I, II, and III malocclusion, total SF-36 scores decreased progressively across the severity levels. However, no statistically significant differences were found in SF-36 scores at 6 months postoperatively among patients with different economic or educational levels, as determined by one-way ANOVA (P > 0.05). At 6 months postoperatively, patients with Class II and Class III malocclusion had lower SF-36 scores compared to those with Class I malocclusion, and patients with Class III malocclusion had lower scores than those with Class II. Multiple linear regression analysis showed that female sex and higher malocclusion classification were independent risk factors for the total SF-36 score at 6 months postoperatively (P < 0.05), while higher expectations regarding surgical outcomes were identified as an independent protective factor (P < 0.05).Conclusion Orthognathic surgery can significantly improve the long-term quality of life of patients with malocclusion, and this improvement is affected by factors such as sex, malocclusion classification, and preoperative expectations of surgical outcomes.