Osteoarthritis Development After Surgical Treatment of Disc Displacement in the Temporomandibular Joints. A Systematic Review.

BACKGROUND: Temporomandibular joint (TMJ) discectomy and disc repositioning surgery (DRS) remain treatment options for disc displacement (DD) when conservative and minimally invasive treatments fail. DRS and discectomy with disc replacement are used, in part, to prevent osteoarthritis (OA) development. OBJECTIVE: To assess evidence for OA development after surgical treatment of TMJ DD by comparing OA development in surgically treated TMJs to OA development in conservatively treated patients with DD. METHODS: A systematic search (Medline, Embase and Cochrane up to 3 October 2024) was performed, and PRISMA was followed. A lack of effect sizes precluded meta-analysis; a descriptive statistical comparison between groups was made (Student's t-test, χ2 test, significance level p < 0.05). RESULTS: Eight observational studies, including discectomy of 117 TMJs (DD with/without reduction; without replacement), 206 comparison TMJs (DDwoR; observation) and one DRS study, met the eligibility criteria. An additional case report met the eligibility criteria but was not included in data synthesis. Heterogeneity in study designs, diagnostic methods and criteria, and mostly high Risk of Bias according to GRADE was found. OA and OA-related findings increased in all discectomy and comparison studies at follow-up. CONCLUSION: A consistent trend of increasing TMJ OA frequency was observed across the included studies in both operated and unoperated TMJs with DD. Most studies provided evidence of very low certainty. This systematic review could therefore not reliably evaluate whether TMJ discectomy is itself responsible for OA development. Further research is needed to determine the influence of surgical treatments of TMJ DD on OA.