Please use this identifier to cite or link to this item:
|Scopus||Web of Science®||Altmetric|
|Title:||Postural control of the human mandible|
|Citation:||Archives of Oral Biology, 2007; 52(4):347-352|
|Part of:||Special Issue: International Mastication Symposium, Brisbane, June 2006 / Kemal S. Türker, Samuel W. Cadden (eds.)|
|Publisher:||Pergamon-Elsevier Science Ltd|
|Timothy S. Miles|
|Abstract:||This article reviews recent experimental evidence explaining the mechanisms that support the mandible in its rest or postural position when the head is stationary and during locomotion. At rest, and during slow jaw movements, there is alternating activation of the jaw-opening and jaw-closing muscles which arises from a central pattern generator. However, this cannot account for the rest position of the mandible even when the head is stationary. Jaw movements and masticatory muscle activity were measured in subjects who stood, walked and ran on a treadmill. Even during walking, there are no bursts of masseter EMG time-locked to heel-landing. However, when subjects ran, the downward movement of the mandible in each step evokes a burst of EMG in the masseters. This is a stretch reflex in the jaw-closing muscles, which acts to limit the downward movement of the mandible relative to the maxilla during locomotion, and to restore the mandibular position towards its rest position. Thus, when the head is stationary, the low-level activity in the jaw-opening and jaw-closing muscles does not contribute to the rest position. Instead, the mandible is supported by passive viscoelastic forces in perioral soft tissues which limit vertical jaw movements even when the head moves gently up and down during walking. When the head moves more vigorously up and down, stretch reflexes in the jaw-closing muscles limit the movement of the mandible. That is, both passive forces and active reflex responses maintain jaw posture within narrow limits during brisk head movements.|
|Keywords:||Mandible; Posture; Stretch reflex; Locomotion; Head movement; Tremor|
|Description:||© 2007 Elsevier Ltd. All rights reserved.|
|Appears in Collections:||Molecular and Biomedical Science publications|
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.