Comparative Evaluation of Treatment Effectiveness in Skeletal Class III Malocclusion: Surgery‐First Approach Using Clear Aligners Versus Fixed Appliances

Objective This study aimed to assess treatment outcomes, identify predictors of relapse in skeletal Class III patients treated with the surgery‐first approach (SFA), comparing fixed appliances (FA) with invisalign clear aligners (CA). Materials and Methods Forty adult patients treated with bimaxillary surgery and SFA were retrospectively enrolled: 20 with FA and 20 with CA. Serial cephalograms were obtained preoperatively (T0) and at 1 week (T1), 3, 6, and 12 months postoperatively (T2–T4). Intergroup differences were assessed using RM‐ANOVA, independent‐samples t ‐tests, and chi‐squared tests. Predictors of relapse were identified using Pearson correlation and multiple linear regression analysis. Results Treatment duration and number of visits revealed no significant differences between the two groups. Most relapses occurred within the first 3 months postoperatively, followed by a gradual decline over the 12‐month period. No significant differences in skeletal stability were observed between the FA and CA groups. However, the FA group exhibited significantly greater maxillary anteroposterior (AP) relapse (−0.98 mm) compared with the CA group (0.39 mm, p < 0.05). Multiple linear regression analysis revealed that FA treatment and greater maxillary advancement were positively associated with a greater magnitude of maxillary AP relapse. Additionally, mandibular AP relapse was associated with greater mandibular changes and less maxillary movement during surgery. Conclusion Treatment efficiency and skeletal stability were similar between FA and CA in SFA‐treated Class III patients, though CA provided better maxillary stability. Close monitoring during the first 3 months post‐surgery is recommended to prevent dental and skeletal side effects. Trial Registration Registration number: ChiCTR2500104667