No significant differences between conservative interventions and surgical interventions for TMJ disc displacement...

The Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase and Scopus databases were searched. In addition reference lists of relevant review articles, textbook chapters and seven relevant journals were hand searched.

Randomised or quasi-randomised controlled trials in patients with clinical and/or radiological diagnosis of acute or chronic DDwoR undergoing any form of conservative or surgical intervention were considered. The primary outcomes were TMJ pain intensity and unassisted/active maximum mouth opening (MMO).

Study selection, data abstraction and quality assessment were conducted independently by two authors. The Cochrane risk of bias tool was used for the quality assessment. Data analysis was based on Cochrane statistical guidelines. For dichotomous data, the estimates of effect of an intervention were expressed as risk ratios (RR) together with 95% confidence intervals (CI). For continuous data, mean differences (MD) with 95% CI were used.

Twenty studies involving a total of 1305 patients were included. Twelve studies were considered to be at high risk of bias with eight being at unclear risk of bias. There was a high degree of clinical heterogeneity among the studies included. Twenty-one comparisons were made among interventions. Meta-analyses were carried out for four comparisons. In most comparisons made there were no statistically significant differences between interventions relative to primary outcomes at short- or long-term follow-up.

Most interventions appear to alleviate DDwoR symptoms, with no significant differences between non-invasive conservative interventions and minimally invasive or invasive surgical interventions. Given the paucity of evidence and the difficulty in interpreting the minimal clinically important difference, this finding suggests that patients with DDwoR probably should be initially managed with the most minimal and least invasive intervention. Escalation to more invasive treatment should occur only in the face of objective clinical need. This, however, should be interpreted in the context of a review based mostly on single studies of unclear to high risk of bias. Future well-conducted research may change or confirm this.