Linked Life Data

6227313

Source:http://linkedlifedata.com/resource/pubmed/id/6227313

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1983-12-20
pubmed:abstractText
An extensive histochemical and quantitative analysis of various portions of the human masseter, the medial pterygoid and the temporal muscles was performed in young adult males with normal intermaxillary relationships and complete dentition. There was marked and locally radical intramuscular variability in the muscle-fibre composition. Each muscle and the subunits of the muscles exhibited a characteristic fibre pattern--both the relative frequency and the diameter of the various fibre types differed significantly between the different portions. The fibre pattern was quantitatively different to that of the human lateral pterygoid muscle and both quantitatively and qualitatively dissimilar to that of the human digastric muscle and that of normal limb and trunk muscles. A large proportion of the fibres were ATPase intermediate fibres and must be regarded as being a part of the normal fibre population of the human mandibular elevator muscles. Type IIA fibres were rare. As muscle-fibre differentiation is considered to be influenced by motoneurone function, it can be assumed that the complex fibre pattern of the jaw-closing muscles is related to the unique function of the human mandibular locomotor system. A functional specialization is suggested providing optimal jaw control. Compared with the lateral pterygoid muscle (with predominantly type I fibres) and the digastric muscle (with predominantly type II fibres), the heterogeneous fibre composition of the jaw-closing muscles probably reflects their more complicated activity pattern and functional requirements. The marked difference between the type I and the type II fibre diameters, type II fibres generally being smaller, might reflect evolutionary changes in the masticatory habits, such as adaptation to refined and soft food. The individual variability in fibre composition suggests various levels of utilization and varying ability to adapt to jaw-muscle hyperactivity, to resist fatigue.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
D
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0003-9969
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
781-95
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Histochemical and morphological muscle-fibre characteristics of the human masseter, the medial pterygoid and the temporal muscles.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't