BALANCE OF MASTICATORY MUSCLES IN SUBJECTS ACROSS DIFFERENT SKELETAL CLASSES.

Irregular antero-posterior relationship of the maxilla and mandible causes unstable occlusion and reduced mandibular movements during muscle contraction, which can cause changes in the masticatory muscle function. Aim: The aim of the present study is to determine whether there is a difference in the asymmetry coefficient (ASIM) of the masticatory muscles (m. temporalis anterior and m. masseter) in patients classified as Class I, Class II and Class III according to Angle, by using the method of surface electromyography (EMG). An additional aim is to determine whether there are differences in the ASIM coefficient in female and male subjects. Material and methods: The sample included 180 subjects, males and females. All subjects were divided into 3 groups of 60 subjects (30 males and 30 females) in skeletal classes I, II and III. An examination of muscle function was conducted by a non-invasive method of surface electromyography. Results: The results of this study showed that there is no statistically significant difference in the ASIM index among groups of respondents (p=0,149). Conclusion: The conclusion of the present study is that there is no statistically significant difference in the coefficient of asymmetry of the masticatory muscles (m. temporalis anterior and m. masseter) in patients across Class I, Class II and Class III according to Angle. The difference in the asymmetry coefficient between female and male subjects is also not statistically significant. [ABSTRACT FROM AUTHOR]