Myoelectric Activity and Mandibular Movement for the Diagnosis of Temporomandibular Disorder

"The sEMG of the anterior temporalis (TA), masseter (MM), sternocleidomastoid (cervical group, CG), and digastric (DA) were recorded simultaneously with an sEMG device (K7/EMG, USA) using disposable silver/silver chloride bipolar surface electrodes.~First, sEMG was conducted on four pairs of muscles (TA, MM, CG, and DA) in the MPP, and subjects were guided to maintain the face and jaw as relaxed as possible. To determine the relative efficiency of muscle function, the second test was performed to measure the sEMG of TA and MM during the maximal biting force against natural dentition. In the third test, subjects were guided to clench three times to monitor early motor unit recruitment as they closed from rest through freeway space to initial tooth contact.~Kinesiographic recordings were performed using a kinesiograph (K7/Computerized Mandibular Scanning (CMS), USA) that measured the maximum mouth opening (MMO) and opening and closing velocities."