Cargando…
Functional Compartmentalization of the Human Superficial Masseter Muscle
Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2015
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4334967/ https://www.ncbi.nlm.nih.gov/pubmed/25692977 http://dx.doi.org/10.1371/journal.pone.0116923 |
_version_ | 1782358262221373440 |
---|---|
author | Guzmán-Venegas, Rodrigo A. Biotti Picand, Jorge L. de la Rosa, Francisco J. Berral |
author_facet | Guzmán-Venegas, Rodrigo A. Biotti Picand, Jorge L. de la Rosa, Francisco J. Berral |
author_sort | Guzmán-Venegas, Rodrigo A. |
collection | PubMed |
description | Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle’s motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20–60% MVBF). |
format | Online Article Text |
id | pubmed-4334967 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-43349672015-02-24 Functional Compartmentalization of the Human Superficial Masseter Muscle Guzmán-Venegas, Rodrigo A. Biotti Picand, Jorge L. de la Rosa, Francisco J. Berral PLoS One Research Article Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle’s motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20–60% MVBF). Public Library of Science 2015-02-18 /pmc/articles/PMC4334967/ /pubmed/25692977 http://dx.doi.org/10.1371/journal.pone.0116923 Text en © 2015 Guzmán-Venegas et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Guzmán-Venegas, Rodrigo A. Biotti Picand, Jorge L. de la Rosa, Francisco J. Berral Functional Compartmentalization of the Human Superficial Masseter Muscle |
title | Functional Compartmentalization of the Human Superficial Masseter Muscle |
title_full | Functional Compartmentalization of the Human Superficial Masseter Muscle |
title_fullStr | Functional Compartmentalization of the Human Superficial Masseter Muscle |
title_full_unstemmed | Functional Compartmentalization of the Human Superficial Masseter Muscle |
title_short | Functional Compartmentalization of the Human Superficial Masseter Muscle |
title_sort | functional compartmentalization of the human superficial masseter muscle |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4334967/ https://www.ncbi.nlm.nih.gov/pubmed/25692977 http://dx.doi.org/10.1371/journal.pone.0116923 |
work_keys_str_mv | AT guzmanvenegasrodrigoa functionalcompartmentalizationofthehumansuperficialmassetermuscle AT biottipicandjorgel functionalcompartmentalizationofthehumansuperficialmassetermuscle AT delarosafranciscojberral functionalcompartmentalizationofthehumansuperficialmassetermuscle |