Arthrocentesis versus conservative treatments for temporomandibular joint disorders: A systematic review with meta-analyses and trial sequential analyses

This systematic review aimed to evaluate the efficacy of arthrocentesis compared to conservative treatments for symptomatic temporomandibular joint disorders. A systematic search for randomized, prospective and retrospective controlled trials was undertaken in five electronic databases. Various patient outcomes and economic evaluations were analysed for short-term (<6 months), intermediate-term (6 months to 5 years) and long-term (≥5 years) follow-up periods. Primary meta-analyses were performed for randomized controlled trials using random-effects models. Arthrocentesis was superior to conservative treatments regarding pain reduction at short-term (MD 14.5 (95% CI 9.7; 19.4), k= 9 RCTs, n= 545 patients, I2= 48%, high quality of evidence) and intermediate-term follow-up (MD 14.2 (95% CI 7.3; 21.1), k=9 RCTs, n= 547 patients, I2= 81%, moderate quality of evidence). Furthermore, arthrocentesis was superior to conservative treatment regarding maximum mouth opening improvement at short-term (MD 2.4 mm (95% CI 0.8; 4.1), k= 8 RCTs, n= 472 patients, I2= 80%, moderate quality of evidence) and intermediate-term follow-up (MD 2.2 mm (95% CI 0.5; 3.9), k= 8 RCTs, n= 468 patients, I2= 75%, moderate quality of evidence). Trial sequential analysis supported the conclusions of all primary meta-analyses. Results were clinically relevant for pain improvement, but not for maximum mouth opening improvement. Results at long-term follow-up and for other study outcomes were either lacking or too heterogenous for meta-analysis, highlighting the need for more standardized, high-quality research.