Abstract
Conventional orthognathic surgery has traditionally followed an orthodontics-first approach (OFA), whereas the surgery-first approach (SFA) has gained attention for its potential to shorten overall treatment time and provide earlier esthetic improvement; however, uncertainties remain regarding skeletal stability, condylar adaptation, temporomandibular joint (TMJ) outcomes, and patient-reported measures. This systematic review compared the clinical outcomes of SFA and OFA in orthognathic surgery, focusing on treatment duration, skeletal stability, condylar changes, TMJ symptoms, patient-reported quality of life, and cost-effectiveness. A systematic search of the Web of Science Core Collection (2009-2025) identified comparative human studies that directly contrasted SFA and OFA, and nine studies met the inclusion criteria for qualitative synthesis. Data were extracted on study design, surgical procedures, outcomes, and follow-up, and risk of bias was assessed using the Newcastle-Ottawa scale. Across studies, SFA consistently shortened overall treatment duration compared with OFA. Skeletal stability at approximately 1 year was broadly comparable between approaches, although counterclockwise mandibular rotation and vertical dimension control were highlighted as critical factors in SFA. Condylar displacement and remodeling patterns were similar, with larger immediate postoperative shifts in SFA that tended to regress toward baseline. TMJ symptoms generally improved after surgery in both groups without meaningful between-group differences. Patient-reported outcomes improved in both cohorts, with SFA offering earlier esthetic benefit by avoiding the preoperative decompensation phase. Cost-effectiveness analyses indicated similar overall costs but a shorter time-to-benefit with SFA. Within the limitations of predominantly observational designs, SFA appears to offer shorter overall treatment time with broadly comparable skeletal, condylar, TMJ, and quality-of-life outcomes to OFA, underscoring the importance of careful case selection, strict protocol adherence, and prospective standardized research to confirm long-term stability and optimize clinical protocols.