The Adjunct Effect of Duloxetine in TMJ Arthrocentesis: A Systematic Review and Meta-Analysis

Background: Temporomandibular disorders (TMDs) are musculoskeletal and joint conditions involving the temporomandibular joint (TMJ), masticatory muscles and related tissues. They are among the most common causes of non-dental orofacial pain and functional limitations, markedly reducing quality of life. This systematic review and meta-analysis assessed the effectiveness of combining duloxetine with TMJ arthrocentesis versus either therapy alone. Materials and Methods: A comprehensive search was conducted across PubMed, Cochrane Library, Google Scholar and ScienceDirect, supplemented by manual reference screening. Only clinical studies involving patients diagnosed with TMDs were included. Eligible studies were randomised or non-randomised clinical trials comparing TMJ arthrocentesis combined with duloxetine versus arthrocentesis alone or duloxetine alone. Treatment effectiveness was assessed based on pain scores, maximum mouth opening (MMO), Hospital Anxiety and Depression (HAD) scale, Patient Health Questionnaire-9 (PHQ-9), interleukin-6 (IL-6) levels in lavage fluid and joint clicking. Risk of bias was assessed using ROB 2 and ROBINS-I tools, and certainty of evidence using GRADE. The significance level adopted for the analysis was set at α = 0.05. Results: This review analysed five clinical trials with 163 patients suffering from TMDs. The findings indicated that the combination of TMJ arthrocentesis and duloxetine treatment significantly reduced pain and improved MMO compared to either treatment alone. No significant differences were found in clicking or IL-6 levels. Adverse effects of duloxetine, such as dizziness and dry mouth, were reported in one study but decreased over time. The certainty of evidence was rated as moderate for pain reduction and low to very low for other outcomes. Conclusion: Duloxetine (30 mg twice daily for 12 weeks) as an adjunct to TMJ arthrocentesis provides a synergistic clinical benchmark for pain relief and MMO improvement. However, due to short-term evidence and the lack of demographic-stratified data, results remain preliminary. Longitudinal RCTs are required to confirm long-term efficacy and safety.