Comparison of Temporomandibular Joint Ankylosis Recurrence Among 3 Surgical Methods: A Single-Centre Retrospective Cohort Study

Introduction and Aims Temporomandibular joint ankylosis (TMJA) severely impairs patients’ mouth-opening function and quality of life. Although multiple surgical techniques have been developed, comparisons of their long-term efficacy remain limited. This study aimed to compare recurrence rates and identify prognostic factors among 3 major surgical approaches via a single-centre retrospective analysis. Methods Patients who underwent TMJA surgery of lateral arthroplasty (LAP), costochondral graft (CCG), or alloplastic total joint replacement (ATJR) from 2001 to 2023 were enrolled. Eligibility required preoperative, 1-week postoperative, and ≥6-month computed tomography follow-up. Multivariable generalised estimating equations (GEEs) were employed to adjust for baseline confounders while comparing recurrence rates across the 3 surgical procedures. They were further used to explore independent risk factors for ankylosis recurrence. Results In total, 149 patients with 204 affected joints were included. Seventy joints underwent LAP, 61 joints CCG, and 73 joints ATJR. After a median follow-up of 13.0 (7.0, 31.2) months (6-112), recurrence occurred in 15 of 204 joints (7.4%) in 11 patients. After adjustment by GEE with Bonferroni correction, the CCG group showed a trend towards higher recurrence (16.4%) than the LAP group (4.3%, P = .051) and the ATJR group (2.7%, P = .040). Osteotomy gap and interpositional materials were significantly associated with recurrence after CCG. The larger the osteotomy gap, the lower the recurrence rate ( P = .025; odds ratio, 0.672; 95% CI, 0.473-0.955). Receiver operating characteristic curve identified the critical osteotomy gap threshold as 8.8 mm (area under the curve, 0.715; P = .037). Temporalis myofascial fat flap (TMF) alone was associated with a higher risk of recurrence than TMF with fat (36.8% vs 7.1%; P = .032). Conclusion CCG demonstrates a trend towards higher recurrence risk than both ATJR and LAP. Osteotomy gap <8.8 mm and TMF alone are associated with higher recurrence after CCG surgery. Clinical Relevance Surgical methods influence ankylosis recurrence. Maintaining an adequate osteotomy gap and selecting fat as interpositional material reduce ankylosis recurrence.