BRUXISM AS A CAUSE OF NEUROPHYSIOLOGICAL ALTERATIONS IN THE TRIGEMINAL COMPLEX

Abstract

All components of the dentoalveolar structures demonstrate close interconnections, especially in the intricate relationship between the nervous and muscular aspects of the temporomandibular joint (TMJ). The muscular system relies hierarchically on the regulatory mechanisms of the nervous system. Consequently, any disruption in the interaction between these components can lead to pathology affecting the overall function of the TMJ. One of the most prevalent myogenic disorders is bruxism, impacting 6-20% of the global population. However, pronounced signs of this condition are observed in only 3-5% of individuals. Bruxism is a multifactorial disorder, and its exact etiology remains unclear. Currently, a primary factor in bruxism is considered to be a disturbance in the body's adaptive capacity to cope with stress. Psychological stress induces hyperactivity in the masticatory muscles, leading to intense clenching of the dentition. This, in turn, results in an overload of the supporting tooth tissues, pathological abrasion of the dentition, dysfunction of the temporomandibular joint (TMJ), and the emergence of general clinical symptoms such as headaches, orofacial issues, and neurological symptoms. The pathophysiological foundation of bruxism lies in the excessive strain on the masticatory muscles, causing ischemia and inflammation in the muscle fibers. The inflammatory process in these fibers triggers a persistent excitation of afferent nerve fibers of type C, giving rise to a dull, aching pain. As bruxism is a chronic condition, there is a physiological restructuring of nerve fibers. This involves the initial peripheral and subsequent central sensitization of C-type nerve fibers, resulting in an inappropriate response of the body to physiological stimuli. For instance, the nervous system begins to interpret minor stimuli as painful (hyperalgesia). Currently, no treatment methods completely eliminate bruxism. Modern treatment approaches involve the use of intraoral dental appliances, pharmacotherapy (with muscle relaxants such as botulinum toxin type A and drugs from the benzodiazepine group), and psychotherapy courses aims to teach patients sleep hygiene, self-control, and the elimination of detrimental habits, including clenching the dentition as a response to psychological stress.