INDAGINI STRUMENTALI ELETTROMIOGRAFICHE IN PAZIENTI CON DISORDINI TEMPOROMANDIBOLARI

Surface electromyography (EMG) can make an objective recording of the masticatory muscle function and dysfunction. Normalized EMG data will inform on the influence of occlusion (teeth contact) on the neuromuscular activity, avoiding individual variability (anatomical variations, physiological and psychological status, etc.) and technical variations (muscle cross-talk, electrode position, etc.). In the first study, the normalized electromyographic characteristics of masticatory muscles in patients with temporomandibular joint disorders (TMD) with long lasting pain (more than 6 months) were analyzed. Overall, patients with long lasting TMD have an increased and more asymmetric standardized activity of their temporalis anterior muscle, and reduced mean power frequencies, relative to healthy controls. In the second study, a group of TMD patients were categorized according to both RDC/TMD and magnetic resonance imaging (MRI) in patients with disk displacement, osteoarthrosis and/or disk displacement. The quantitative sEMG characteristics of their masticatory muscles were examined. A significant correlatio between diagnostic data obtained by MRI and sEMG was found, permitting to propose sEMG as a first diagnostic tool, reserving MRI to more complex situations. In the third study, the surface electromyographic spectral characteristics of masticatory and neck muscles during the performance of maximum voluntary clench (MVC) tasks, were considered. A set of data to characterize the sEMG spectral characteristics of jaw and neck muscles in young adult subjects performing MVC tasks currently in use within the dental field was obtained. The outcomes suggest that the proposed method could be a useful tool to evaluate functionally altered stomatognathic conditions. Diagnosis of alterations of the stomatognatic apparatus and assessment of the effects of therapy would both profit from this quantitative approach, thus reducing the discordance among several clinical examinations.