Effect of Duchenne muscular dystrophy in actuation of the stomatognathic system - electromyographic analysis, masticatory efficiency, muscle thickness and strength of maximum molar bite

The Duchenne Muscular Dystrophy is caused by a change in the locus xp21 of chromosome X, essentially in the gene (dys) that encodes a protein called dystrophin. The bearers of the disease present clinical picture of loss of muscle strength in a progressive way, starting on the lower limbs. This cross-sectional observational study has to analyze the pattern of electromyographic activity, masticatory efficiency, muscle thickness and the strength of molar bite maximum of individuals with Duchenne Muscular Dystrophy. Were selected 40 individuals of the male gender with age between 04 to 15 years, with a mean age of 10 ± 4 years, divided into two groups matched for age, weight and height. GI - carriers of Duchenne Muscular Dystrophy (n= 20). G2 - Control: healthy individuals (n= 20). The individuals were submitted to the evaluation of the stomatognathic system by surface electromyography during the clinical conditions that required postural control of the jaw, and chewing muscles fatigue, masseter and temporal sternocleidomastoid, ultrasonography of the muscles mentioned in the clinical condition of rest and habitual maximum intercuspation and assessing the strength of molar bite maximum on the first molars. The statistical analysis was performed by SPSS 21.0 using the t test (p< 0.05). In electromyographic evaluation it was found that changes in patterns of muscular activity in clinical conditions related to the posture of the mandible. In masticatory efficiency it was observed higher EMG activity for the control group during the mastication of Parafilm, of the grape raisins and the peanuts. On muscle fatigue was noted frequently elevated values of median for individuals with Duchenne muscular dystrophy. In the evaluation of muscle thickness, in individuals with Duchenne dystrophy muscular, we found higher muscle thickness for all assessed muscles during rest and maximum intercuspation usual, except for the masseter muscles in condition of habitual maximum intercuspation. On the strength of molar bite maximum note-if smaller forces us bearers of dystrophy. It is concluded that there are no changes of the stomatognathic system in muscle activity, masticatory efficiency, muscle thickness and strength of maximum molar bite procreate by Duchenne muscular dystrophy. (AU)