Ageing and surface EMG activity patterns of masticatory muscles. J Oral Rehabil

Department of Morphology, Stomatology and Physiology of the Ribeirão Preto Dental School (RPDS), University of São Paulo, São Paulo, Brasil.
Journal of Oral Rehabilitation (Impact Factor: 1.68). 02/2010; 37(4):248-55. DOI: 10.1111/j.1365-2842.2010.02051.x
Source: PubMed


The purpose of this study was to evaluate the influence of age on the electromyographic activity of masticatory muscles. All volunteers were Brazilian, fully dentate (except for Group I - mixed dentition), Caucasian, aged 7-80, and divided into five groups: I (7-12 years), II (13-20 years), III (21-40 years), IV (41-60 years) and V (61-80 years). Except for Group V, which comprised nine women and eight men, all groups were equally divided with respect to gender (20 M/20 F). Surface electromyographic records of masticatory muscles were obtained at rest and during maximal voluntary contraction, right and left laterality, maximal jaw protrusion and maximal clenching in the intercuspal position. Statistically significant differences (P < 0.05) were found in all clinical conditions among the different age groups. Considerably different patterns of muscle activation were found across ages, with greater electromyographic activity in children and youth, and decreasing from adults to aged people.

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    • "These effects have not yet been investigated in the spinal musculature of quadrupeds. Surface electromyography (sEMG) is currently successfully used to identify muscle activity changes in human diseases, such as Parkinson's (Cecílio et al., 2010), and ageing, for example in masticatory muscles (Meigal et al., 2009). Many of these findings are thought to be transferrable to the activity of deeper muscles, but clearly, without evidence based data, this remains an assumption prior to the measurement of the deeper muscles themselves. "
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