Masticatory muscular activation in elderly individuals during chewing

Abstract

Old-age is the last stage of human evolution and, unfortunately, the ageing of the oral cavity and masticatory system seems accelerated. As a consequence, there is a reduction in the amount of food ingested, which can lead to an imbalance in nutrition. The purpose of this study was to investigate the levels of muscular activation of elderly individuals, during chewing, and to compare with young individuals. An electromyographical analysis of the masticatory system in 10 individuals aged between 60 and 75 years (elderly group) and a similar number between 23-30 years old (young group - control) was carried out. The analysis was performed using a MyoSystem-Br1 electromyographer with differential active electrodes. The test was recorded during functional conditions, and the muscles assessed were the temporalis and masseter. Data were normalised by maximum voluntary contraction (MVC), and the results were analysed using an independent t-test for comparison between the groups. The normalised electromyographic data obtained showed significant differences in both groups. Comparing the normalised values obtained for MVC, the mean values for the masseter and temporalis muscles of elderly group were statistically lower (p </= 0.05) than control group for harder foods, but there were no significant differences for food with the lowest consistency. It can be concluded that elderly individuals show slight hypoactivity of their masticatory musculature during chewing when compared to young individuals.