Management of chronic pain secondary to temporomandibular disorders: a systematic review and network meta-analysis of randomised trials
Authors: Yao Liang , Sadeghirad Behnam , Li Meixuan , Li Jing , Wang Qi , Crandon Holly N , Martin Grace , Morgan Rebecca , Florez Ivan D , Hunskaar Birk Stokke , Wells Jeff , Moradi Sara , Zhu Ying , Ahmed Muhammad Muneeb , Gao Ya , Cao Liujiao , Yang Kehu , Tian Jinhui , Li Jialing , Zhong Linda , Couban Rachel J , Guyatt Gordon H , Agoritsas Thomas , Busse Jason W 
Published: December 2023

Abstract

Objective
We explored the comparative effectiveness of available therapies for chronic pain associated with temporomandibular disorders (TMD).

Design
Systematic review and network meta-analysis of randomised clinical trials (RCTs).

Data sources
MEDLINE, EMBASE, CINAHL, CENTRAL, and SCOPUS were searched to May 2021, and again in January 2023.

Study selection
Interventional RCTs that enrolled patients presenting with chronic pain associated with TMD.

Data extraction and synthesis
Pairs of reviewers independently identified eligible studies, extracted data, and assessed risk of bias. We captured all reported patient-important outcomes, including pain relief, physical functioning, emotional functioning, role functioning, social functioning, sleep quality, and adverse events. We conducted frequentist network meta-analyses to summarise the evidence and used the GRADE approach to rate the certainty of evidence and categorise interventions from most to least beneficial.

Results
233 trials proved eligible for review, of which 153—enrolling 8713 participants and exploring 59 interventions or combinations of interventions—were included in network meta-analyses. All subsequent effects refer to comparisons with placebo or sham procedures. Effects on pain for eight interventions were supported by high to moderate certainty evidence. The three therapies probably most effective for pain relief were cognitive behavioural therapy (CBT) augmented with biofeedback or relaxation therapy (risk difference (RD) for achieving the minimally important difference (MID) in pain relief of 1 cm on a 10 cm visual analogue scale: 36% (95% CI 33 to 39)), therapist-assisted jaw mobilisation (RD 36% (95% CI 31 to 40)), and manual trigger point therapy (RD 32% (29 to 34)). Five interventions were less effective, yet more effective than placebo, showing RDs ranging between 23% and 30%: CBT, supervised postural exercise, supervised jaw exercise and stretching, supervised jaw exercise and stretching with manual trigger point therapy, and usual care (such as home exercises, self stretching, reassurance).
Moderate certainty evidence showed four interventions probably improved physical functioning: supervised jaw exercise and stretching (RD for achieving the MID of 5 points on the short form-36 physical component summary score: 43% (95% CI 33 to 51)), manipulation (RD 43% (25 to 56)), acupuncture (RD 42% (33 to 50)), and supervised jaw exercise and mobilisation (RD 36% (19 to 51)). The evidence for pain relief or physical functioning among other interventions, and all evidence for adverse events, was low or very low certainty.

Conclusion
When restricted to moderate or high certainty evidence, interventions that promote coping and encourage movement and activity were found to be most effective for reducing chronic TMD pain.

Registration
PROSPERO (CRD42021258567)