Efficacy of mandibular manipulation technique for temporomandibular disorders patients with mouth opening limitation: a randomized controlled trial for comparison with improved multimodal therapy.

PURPOSE: Manual therapy has been used for the treatment of patients with temporomandibular disorders (TMD) with mouth-opening limitations. However, the curative effect of manipulation differs among researchers, and its necessity remains controversial. The purpose of this study was to confirm the efficacy of manipulation using a randomized controlled trial (RCT).

METHODS

A total of 61 TMD patients who had mouth-opening limitation (upper and lower middle incisor distance ≤35mm) were selected. They were divided into two treatment groups: conventional treatment (n=30) and conventional treatment plus manipulation (n=31). The conventional treatment included two types of self-exercise: cognitive behavioral therapy for bruxism and education. Mouth-opening limitation, orofacial pain, and temporomandibular joint (TMJ) sounds were recorded from baseline to 18 weeks after baseline. These parameters were statistically compared between the two treatment groups by using analysis of variance (ANOVA) and Scheffe's test to assess mouth opening distance and pain; TMJ sounds were compared using Mann-Whitney U test.

RESULTS

No statistical difference was observed between the two treatment groups except for mouth-opening limitation after treatment at the first visit. Subgroup analyses, stratified according to the pathological type of TMD, indicated a similar trend.

CONCLUSIONS

The efficacy of manipulation seems to be limited, in contrast to our expectations, and improved execution of therapeutic exercises has a similar effect to that of manipulation during long-term observation. The advantage of manipulation was observed only during the first treatment session. The RCT was registered in the University Hospital Medical Information Network in Japan (UMIN-CTR: 000010437).