The comparative efficacy of relaxation training and masseter EMG feedback in the treatment of TMJ dysfunction.

The present series of single case studies was designed to evaluate the comparative efficacy of masseter EMG feedback with progressive relaxation training in the treatment of TMJ dysfunction. Study 1 employed a multiple baseline design across the symptoms of jaw pain, jaw tension and shoulder pain in a patient with chronic TMJ problems. The results indicated that relaxation training was the treatment responsible for improvements in subjective ratings of jaw pain and tension, whereas masseter EMG feedback provided little additional benefit. Trapezius EMG feedback was necessary to provide improvements in ratings of shoulder pain. Study 2 consisted of four single case designs in which masseter EMG feedback and relaxation training were compared with four TMJ patients. Results indicated that relaxation produced clear improvements in pain and tension ratings for two patients, a combination of EMG feedback and relaxation training resulted in slight improvements in one patient, and neither treatment procedure was effective for the final patient. The possibility of wide-scale application of relaxation training with TMJ patients and the need for further controlled research of masseter EMG feedback were discussed.