Influence of Breathing Modes and Facial Growth Patterns on Electromyographic Fatigue of Masticatory Muscles in Children

Abstract Introduction Changes in breathing patterns affect the harmonious development of the structures of the craniofacial system, leading to changes in posture, occlusion, and facial growth patterns. However, little is known about how these changes influence the muscle contraction patterns, either at rest or while functioning, and either in a normal or unbalanced condition. Objective To study the masseter and anterior temporal muscles fatigue during mastication in nasal- and mouth-breathing children, also considering their facial growth patterns. Methods: A total of 70 children aged 6 to 12 years old who met the study criteria were assessed. Speech-language-hearing, otorhinolaryngologic, and cephalometric assessments were performed to divide them into groups. In the electromyographic assessment, the children were asked to chew gum following a metronome until they felt fatigued. The median frequency of the muscles was analyzed at 15, 30, 45, and 60seconds of mastication.The reported time of fatigue perception was recorded. The data were analyzed with analysis of variance (ANOVA) and the Kruskal-Wallis and the Mann-Whitney U tests. Results There were no median frequency decrease patterns nor differences in the myoelectric manifestations and reported time of fatigue between the groups. Conclusion The masticatory muscles did not reveal fatigue in the electromyographic analysis; however, the fatigue time was reported, despite the absence of physiological fatigue. The breathing mode, the facial growth pattern, and the association between them did not interfere with the behavior of the median frequency of the electromyographic signal and the fatigue time perception.

Electromyographic analysis of suprahyoid musculature before and after therapy taping in young women

ABSTRACT Purpose: to compare the effects of a tongue coupling program with and without therapy taping on suprahyoid muscles in young women. Methods: participants were 14 women aged 19 to 25 years, allocated into two groups. The Experimental Group did 15-second tongue coupling in combination with tape use without tension, while the Control Group only did tongue coupling. Electromyography was used to analyze the suprahyoid muscles before, during, and after training, at rest, in maximum voluntary contraction, and in swallowing. The domains of amplitude and frequency of the electromyography signal were considered, in situations before, after and during the intervention, after which, the therapy taping appreciation questionnaire was administered. The chi-square test was used for clinical variables, Student's t-test, Wilcoxon test, and Mann-Whitney U test were used to compare before and after the intervention, and the Friedman ANOVA test was used for the training. The significance level was set at 5%. Results: no statistically significant differences were found in muscle activity when comparing values before and after the intervention at rest and in swallowing in either group or between them. However, there was a general increase in maximum voluntary contraction in both regions, in both groups. There were positive impressions regarding tape use. Conclusion: this approach in this population did not interfere with muscle activity, although there were positive qualitative results regarding the perception of the stimulated area.

Tongue coupling as a therapeutic strategy: electromyographic analysis of different training approaches / Acoplamento de língua como estratégia terapêutica: análise eletromiográfica de diferentes propostas de treino

ABSTRACT Purpose: to compare the effect of two tongue coupling approaches on the electrical activity of the suprahyoid musculature in young women. Methods: the sample comprised 47 women aged 18 to 27 years, distributed into groups, according to exercise training time - 10 and 15 seconds. They answered an initial questionnaire and were submitted to speech-language-hearing clinical assessment, body mass index calculation, and electromyographic assessment. Two electrodes were positioned bilaterally on the skin in the region of the suprahyoid musculature to pick up the electromyographic signal. The women performed the tests with resting periods and maximum voluntary contraction, coupling the tongue with the hard palate as strongly as possible, followed by three training series coupling the tongue with the palate. The collected data regarding amplitude and frequency of the myoelectrical activity were analyzed, by comparing the performance within the two groups and one another with the Friedman and One-Way ANOVA tests, and Mann-Whitney U test, at the 5% significance level. Results: no statistical significance was observed between the groups when comparing their performance in the series, neither was there any decrease in the median frequency in each group while performing the three series. Conclusion: no effect on the electrical activity of the suprahyoid musculature was found in young women when they performed isometric tongue coupling exercise training.

RESUMO Objetivo: comparar o efeito, na atividade elétrica dos músculos supra-hióideos, de duas propostas de realização do acoplamento de língua por mulheres jovens. Métodos: participaram da amostra 47 mulheres, com idade entre 18 e 27 anos, distribuídas nos grupos conforme treino do exercício por 10 e 15 segundos. Foram submetidas a um questionário inicial, avaliação clínica fonoaudiológica, cálculo do índice de Massa Corporal e avaliação eletromiográfica. Para captação do sinal eletromiográfico, foram posicionados bilateralmente sobre a pele dois eletrodos, na região dos músculos supra-hióideos. Foram realizadas as provas de repouso e contração voluntária máxima mediante acoplamento de língua com força máxima, seguidos do treino com acoplamento da língua ao palato por três séries. Os dados coletados foram analisados quanto à atividade mioelétrica nos níveis da amplitude e da frequência, sendo comparados os desempenhos dos dois grupos entre si e dentro de cada grupo através dos Teste ANOVA de Friedmann, One-Way e Teste U-Mann-Whitney. Foi considerado nível de significância de 5%. Resultados: não foi observada significância estatística ao comparar o desempenho das séries entre os grupos, assim como não houve decréscimo da frequência mediana durante a realização das três séries em cada grupo. Conclusão: não foi encontrado efeito na atividade elétrica dos músculos supra-hióideos quando executado treino de exercício isométrico de acoplamento de língua em mulheres jovens.