Do intra‐articular injections of analgesics improve outcomes after temporomandibular joint arthrocentesis?: A systematic review and meta‐analysis

OBJECTIVES: Intra-articular analgesics are increasingly being used after temporomandibular joint (TMJ) arthrocentesis but without clear evidence on its efficacy. The aim of this study was to review the role of intra-articular analgesic injected after TMJ arthrocentesis in improving post-operative outcomes. METHODS: PubMed, Embase, Scopus, BioMed Central, CENTRAL and Google Scholar databases were searched from inception up to 15th April 2020. Randomised controlled trials (RCTs) on adult patients with temporomandibular joint disorders (TMDs) comparing any intra-articular analgesic with control after arthrocentesis were included. Risk of bias was assessed by Cochrane Collaboration's Risk of Bias-2 tool. RESULTS: Nine RCTs were included. Four studies used non-steroidal anti-inflammatory drugs (NSAIDs) and five used opioids after arthrocentesis. Descriptive analysis of NSAID studies indicated that intra-articular NSAIDs may not improve pain and maximal mouth opening (MMO) after TMJ arthrocentesis. Meta-analysis indicated a statistically significant reduction of pain with the use of opioids at 1 week, 1, 3, and 6 months. Similarly, MMO was significantly improved with intra-articular opioids at 1 week, 1 and 6 months. Data were analysed from a limited number of studies with a small sample size. The quality of the included studies was low. CONCLUSIONS: Low-quality evidence suggests that intra-articular NSAIDs may have no effect on pain and MMO after TMJ arthrocentesis. Intra-articular opioids may improve pain and MMO at short-term follow-up. Results are to be interpreted with caution considering several limitations of the review. Further high-quality trials with large sample size are needed to provide better evidence.