[Electromyographic characteristics of temporal and masticatory muscles in patients with compression-dislocation dysfunction of temporomandibular joints of different severity]

Introduction: The main causes of dysfunctional conditions of the temporomandibular joints (TMJ), are occlusal, neurogenic, orthodontic disorders. The muscular component of TMJ is determines the dynamic anatomical and functional state of the mandible Therefore, in the diagnosis of dysfunctions and understanding of their pathogenesis belongs to the electromyographic method of investigation. The aim of the work was a comparative assessment of the bioelectrical activity of the actual chewing and temporal muscles in patients with musculo-articular compressiondislocation dysfunction of the TMJ of various severity.

Materials and methods: Electromyographic studies of temporal and masticatory muscles were performed in 43 patients. Was assess maximal parameters were recorded with the greatest compression of teeth and in the periods of chewing on the side of the pain symptom and on the opposite side (μV), the frequency of filling the myogram (Hz), the time of activity (Ta) and the resting time (Tc), coefficient "K", which determines the ratio of the processes of activity and rest with functional samples (K = Ta / Tc).

Results and conclusions: The main feature of the functional properties of the studied muscles in the compression-dislocation dysfunction of the TMJ is the prevalence of the maximum indices of their bioelectrical activity on the side of the joint with the dislocation of the articular head of the mandible in comparison with the joint, which is in a compression state both during periods of compression of the teeth and mastication. This kind of discoordination in the work of the muscular masticatory apparatus is reflected in the severity of the course of dysfunction.