Treatment of painful temporomandibular joint disc displacement without reduction: network meta-analysis of randomized clinical trials

There is currently no consensus on the best treatment for painful temporomandibular disc displacement without reduction (DDwoR), and no network meta-analysis (NMA) of randomized clinical trials (RCTs) comparing all types of treatments for this condition has been conducted. The objective of this study was to compare and rank all treatments for DDwoR, including conservative treatments, occlusal splints, low-level laser therapy (LLLT), arthrocentesis (Arthro) alone, Arthro plus intra-articular injection (IAI) of platelet-rich plasma (PRP), Arthro plus IAI of hyaluronic acid (HA), Arthro with exercises, Arthro plus occlusal splints, and manipulative therapy. Outcome variables were pain intensity on a visual analogue scale (VAS) and maximum mouth opening (MMO, mm). The mean difference with 95% confidence interval was estimated using Stata software. The GRADE system was used to assess the certainty of the evidence. A total of 742 patients from 16 RCTs were included in the NMA. Both direct meta-analysis and NMA showed that Arthro with IAI of co-adjuvants provided better pain reduction in the short term (≤3 months) than Arthro alone. However, the quality of the evidence was very low. In the intermediate term, Arthro alone or combined with co-adjuvants provided better pain reduction than conservative treatment, but with low-quality evidence. Conservative treatment significantly increased MMO in the short term compared to other treatments. In conclusion, the results of this NMA suggest that arthrocentesis with intra-articular injection of adjuvant medications may be superior to conservative treatments in reducing pain intensity at long-term follow-up, while no significant differences were found for the MMO outcome. However, the quality of evidence was generally low to very low, and further RCTs are needed to confirm these findings.