Avaliação eletromiográfica da proporcionalidade de atividade elétrica entre os músculos masseter e temporal em homens de diferentes tipos faciais

Abstract

Given that the Stomatognathic System (SA) is the subject of study in Dentistry and that mastication is its main function, studying the components of this system and their function is fundamental. The SA is composed of different organs and tissues, including the muscles of mastication, two of which stand out: the masseter and temporalis. The superficial bundle of the masseter elevates the mandible and moves it forward, while the deep bundle elevates it and maintains occlusion. The temporalis elevates the mandible, and its deeper bundle retrudes it. Thus, in the movement of mandible elevation, the masseter is the agonist muscle and the temporalis is the synergist. However, studies on the proportionality of activity performed by each of these muscles during the masticatory process are lacking. Therefore, this study aims to investigate the proportionality of electrical activity between the two muscles in each of the three facial types recommended in the literature: brachycephalic, dolichocephalic, and mesocephalic, according to the Facial Morphological Index (FMI). This study is basic, deductive and quantitative in nature. Electromyographic data were collected from 15 male volunteers with different facial profiles in three situations: rest, chewing, maximum habitual intercuspation (MIH) with clenching. After collection, the data were subjected to statistical analysis of percentage using the Friedman test with p<0.05. Thus, the results obtained did not present statistical significance in this sample in any of the three situations.