CHARACTERISTICS OF THE BIOELECTRIC ACTIVITY OF THE MASTICATORY MUSCLES IN PATIENTS WITH HEARING DEPRIVATION IN PERMANENT OCCLUSION IN THE PHYSIOLOGICAL STATE

Abstract

The study of the muscles of the maxillofacial area both in normal and pathological occlusions is the area of great interest, since muscle function is an indicator of complex functional relationships of the dento-mandibular system. Hearing impaired patients have many features related to the functional features of the maxillofacial area due to the slight or complete lack of use of facial muscles during speech or through the use of sign language. Hearing impaired children have 100% of bite pathology.
 The functional state of chewing and temporal muscles in schoolchildren with hearing loss in constant bite at rest was studied. Twenty-five hearing impaired students with permanent dentistry were studied at Poltava Special Boarding School for Deaf Children, who formed the study group. Among them, there were 13 women (62.5%) and 12 men (37.5%). The mean age was 18.7 ± 1.31 years. The control group used the data of the study of patients with constant physiological bite without hearing disorders, determined by M. I. Dmytrenko. The average age was 21.3 ± 1.25 years.
 The bioelectric activity of the chewing muscles was examined on an electromyographic complex. The average values of oscillation amplitude (μV) of muscle biopotential on both sides were determined. Muscle biopotentials were recorded for five seconds in a state of physiological calm with closed lips.
 The results show that all indicators of PD of chewing muscles in a state of physiological rest are almost 2 times higher (p˂0,05) in comparison with those of patients with normal hearing and physiological bite. The work of the temporal muscles in schoolchildren with hearing loss is characterized by symmetry. There is also greater electrical activity of the temporal muscle than the masticatory muscles at rest, unlike normal hearing patients.
 All patients with hearing impairment had 100% prevalence of dental anomalies. Biopotential of chewing muscle of I class. for angle was 2.7 times higher than in patients with the control group. The biopotential of the temporalis muscle in the ICE was 1.8 times higher (p˂0.05), which indicates a constant tension or insufficient muscle relaxation in patients with ICE. In patients with hearing loss of II class. for angle, the average value of the biopotential of the chewing muscle was 2.3 times higher than in patients in 2 group, the temporal muscle was 1.5 times higher.