The state of the masticatory muscles in patients with temporomandibular joint dysfunction and signs of undifferentiated connective tissue dysplasia

Blinov Mikhail Sergeevich, Borodulina Irina Ivanovna, Tegza Nikolay Vasilyevich, Ratnikov Vyacheslav Albertovich

Connective tissue defects in undifferentiated dysplasia (NDST) lead to the formation of defective internal structures of the TMJ, a decrease in the size of the fibers of striated musculature and muscle mass, which is manifested by TMJ dysfunction. The object of the in-depth study were patients of 3 groups: group 1 (clinical) – 20 people with TMJ dysfunction and signs of NDST; group 2 (comparison) – 22 people with TMJ dysfunction without signs of NDST; 3 clinical control group - 20 somatically healthy volunteers with signs of constitutional hypermobility, not presenting a sting to the TMJ. Based on the data of the performed electromyography and myotonometry and computed tomography examination of the muscular apparatus in the "soft-tissue windows" mode, it was found that TMJ dysfunction with signs of PDST is accompanied by a significant decrease in the period of bioelectric activity of the chewing and temporal muscles proper, an increase in the rest period throughout the chewing cycle and a decrease in the amplitude of the electromyogram oscillations: decrease in the tone of the chewing and temporal muscles proper, both at rest and with maximum compression of the jaws against the background of a decrease in elasticity gain; hypotrophy of the masticatory, temporal, medial and lateral pterygoid muscles proper.

Keywords:dysfunction, temporomandibular joint, undifferentiated connective tissue dysplasia, masticatory musculature, electromyography, myotonometry.