Pain relief and Electromyographic evaluation in patients suffering from pain dysfunction syndrome of the temporomandibular joint

Aims: To evaluate the effectiveness of the analgesic response to two electric physiotherapy techniques: electroacupuncture (E.A.) and transcutaneus electrical nerve stimulation (T.E.N.S.), in patients suffering from the pain dysfunction syndrome. Moreover, we checked the effects of E.A. and T.E.N.S. on the masseter and temporalis anterior muscles of the same patients. Method: Fourteen patients, (8 females and 6 males, aged 18-51), suffering from TMJ pain dysfunction syndrome were divided into two groups and treated 7 with E.A. and 7 with T.E.N.S.; we used continous waves at 10-50 Hz for each 20 minutes treatment; the Scott-Huskisson Visual Analogue Scale (V.A.S.) was used to assess the intensity of pain both before and after the treatments. We have investigated the changes in activity of two masticatory muscles, the masseter and temporalis anterior, using superficial electromyography. Results: Our results show that, in relation to the changes in the masseter and temporalis muscle activity, both E.A. and T.E.N.S. have a good affect on the balance of the muscle; meanwhile, using the Signed Ranked Test, the E.A. is more effective than T.E.N.S. in relieving the pain, with a significant statistical difference (p=0.03). Conclusions: The results indicate that E.A. and T.E.N.S. are effective physiotherapy techniques and suggest their use to relieve pain and to balance masticatory muscles in patients suffering from T.M.J. pain dysfunction syndrome.