Abstract
Patients with TMJ disfunction or toothache have been treated by Acupuncture theraphy at the Pain Clinic in Osaka Dental University.
This Acupuncture theraphy is practiced by inserting the needle on the acupoint ST III (No.7) approximately 3540mm depth and stimulating with low frequency electric current. The acupoint ST III (No.7) is located in the center of the half-round area between the mandibular notch of the mandible and the malar arch.
Authors took an interest of the possibility of locating of the needle into the lateral pterygoid muscle during Acupuncture therapy.
And EMG recording of the lateral pterygoid muscle was tried through this needle as an electrode. EMG activity through the needle electrode was appeared during the protrusive movement of the mandible and the Jaw opening movement.
And this EMG activity was an antagonistic realtionship with that of the posterior part of the temporal muscle during anterior-posterior and lateral mandibular movement.
From these two facts, the EMG waves through the needle electrodes were proved to be the activity of the lateral pterygoid muscle.
