Effect of Therapeutic Jaw Exercises in the Treatment of Masticatory Myofascial Pain: A Randomized Controlled Study

Aims: To study the effect and cost-effectiveness of jaw exercise treatment in patients with masticatory myofascial pain. Methods: A total of 97 patients with myofascial pain according to the RDC/TMD were randomized into three groups: (1) jaw exercises; (2) stabilization appliance; or (3) no treatment. After 3 months, the patients were evaluated according to the following instruments: pain intensity according to a visual analog scale (VAS); global improvement according to the Patient Global Impression of Change scale (PGIC); depression and anxiety according to the Hospital Anxiety and Depression Scale (HADS); jaw function according to the Jaw Functional Limitation Scale (JFLS-20); consumption of analgesics; and frequency of tension-type headache. Results: Pain intensity during jaw movement decreased significantly more in the jaw exercise group compared to the no treatment group (P < .001). There was no statistically significant difference between the jaw exercise and stabilization appliance groups in this aspect. The patients in the treatment groups reported greater improvement on the PGIC compared to the no treatment group (P < .001). There was a significant decrease in headache frequency (P = .028), consumption of analgesics (P = .007), and JFLS scores (P = .008) in the jaw exercise group compared to the no treatment group. In the jaw exercise group, patients had fewer appointments and a lower mean treatment time compared to the group that received stabilization appliance treatment. Conclusion: Jaw exercises are effective in reducing pain intensity, headache, and consumption of analgesics in patients with masticatory myofascial pain. Jaw exercises are also cost-effective when compared to treatment with a stabilization appliance.

dentistry; exercise; facial pain; physical therapy modalities; temporomandibular joint dysfunction syndrome

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