Dissertação
Comparação de características miofuncionais e eletromiográficas de crianças obesas e eutróficas
Fecha
2013-08-26Autor
Favero, Talita Cristina
Institución
Resumen
Obesity is a chronic, complex and multifactorial etiology that determines
several complications in childhood and adult age. Among the nutritional disorders,
obesity is the one that creates the most musculoskeletal problems, inferring the
importance of studies facing this population in the context of excessive weight gain
and its contribution to a change in posture and function of the stomatognathic
system. Thus, this study aimed to evaluate and compare the structures, functions
and pattern of muscle electrical activity of the stomatognathic system of obese and
eutrophic children through miofunctional evaluation and surface electromyography.
Were evaluated 32 children between 6 and 12 years old, students from 1st to 6th
grade in a public elementary school in the city of Santa Maria-RS. The children were
divided into two groups according to their nutritional condition - 16 obese and 16
eutrophics. The variables studied included natural feeding, bottle feeding (artificial
feeding), nutritional condition and miofunctional evaluation, according to the protocol
MBGR; in addition, to electromyographic evaluation were evaluated the masticatory
muscles (anterior temporal muscle, masseter and orbicularis oris) activities and
maximal voluntary contraction (MVC), resting, chewing (directed and habitual) and
swallowing. For statistical analysis were used frequency distribution, mean, median,
first and third quartiles, t-Student Test, Chi-square, Fisher Exact and Wilcoxon,
considering a significance level of p<0.05. Results related to orofacial evaluation
showed that obese children received natural feeding for a shorter period of time and
made more use of the bottle than eutrophic children. Mobility conditions, appearance
and posture of the stomatognathic system were similar between groups. Changes of
tone structures were observed in a greater number in the eutrophic group. Regarding
the characteristics of chewing, it was observed that obese made greater number of
chewing strokes and for a longer period of time than eutrophic individuals. There was
no difference in speed and side of mastication compared between groups. As for
electromyographic evaluation of masticatory muscles, the obese presented similar
muscle activation compared to eutrophics during activities of MVC and rest
(isometrics). However, for dynamic activities - chewing, swallowing and chewing
directed - the obese had lower median muscle activation than eutrophic in most
situations proposals in the activation period (on) and in the off period, with a statistically significant difference (p<0.05) for all muscle groups studied. Based on the
results of this research, it was concluded that the nutritional status appears to have
not much influence on the characteristics of the stomatognathic system in
schoolchildren, but about their functions. These findings confirm the hypothesis that
obese children, probably because of excessive facial fat, present changes in the
conditioning of the masticatory muscles, which are reflected in the performance of
the stomatognathic system’s functions.