Biomaterial Database

Effects of jaw clenching, jaw movement and static jaw position on facial skin sensitivity to non-painful electrical stimulation in man. 1993

P Kemppainen, and H Leppänen, and A Waltimo, and A Pertovaara

Department of Physiology, University of Helsinki, Finland.

The effects of isometric jaw clenching, static jaw position and jaw movement on electrically evoked perception thresholds of the facial skin of the mental region were studied in healthy human subjects. Exercise consisted of brief (1 s) isometric contractions of jaw-closing muscles against a static load (30% of the maximum force), or continuous jaw movements at two different frequencies (1 and 3 Hz). A visual cue was used to indicate the start and end of the isometric exercise (duration 1 s.). Isometric jaw clenching induced a significant elevation of perception thresholds in the skin of the lower jaw just before and during the early electromyographic response of the jaw-closing muscles. This elevation was attenuated before the end of the exercise. Corresponding thresholds evoked by electrical stimulation applied to the dorsum of the hand were not changed by isometric jaw clenching. Changes in static jaw position did not have any effect on detection thresholds. Continuous 'masticatory-like' jaw movements produced a velocity-dependent reduction of sensitivity in the facial skin. The suppression was significantly stronger than that produced by isometric jaw exercise. An imagined isometric biting exercise, which presumably activated the supplementary motor cortex, did not cause any threshold elevations. The results indicate that isometric jaw clenching as well as cyclical jaw movements produce segmentally a phasic, rapidly attenuating masking of facial skin sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007537	Isometric Contraction	Muscular contractions characterized by increase in tension without change in length.	Contraction, Isometric,Contractions, Isometric,Isometric Contractions
D007568	Jaw	Bony structure of the mouth that holds the teeth. It consists of the MANDIBLE and the MAXILLA.	Jaws
D008297	Male		Males
D008406	Masseter Muscle	A masticatory muscle whose action is closing the jaws.	Masseter Muscles,Muscle, Masseter,Muscles, Masseter
D008409	Mastication	The act and process of chewing and grinding food in the mouth.	Chewing
D008410	Masticatory Muscles	Muscles arising in the zygomatic arch that close the jaw. Their nerve supply is masseteric from the mandibular division of the trigeminal nerve. (From Stedman, 25th ed)	Masticatory Muscle,Muscle, Masticatory,Muscles, Masticatory
D009044	Motor Cortex	Area of the FRONTAL LOBE concerned with primary motor control located in the dorsal PRECENTRAL GYRUS immediately anterior to the central sulcus. It is comprised of three areas: the primary motor cortex located on the anterior paracentral lobule on the medial surface of the brain; the premotor cortex located anterior to the primary motor cortex; and the supplementary motor area located on the midline surface of the hemisphere anterior to the primary motor cortex.	Brodmann Area 4,Brodmann Area 6,Brodmann's Area 4,Brodmann's Area 6,Premotor Cortex and Supplementary Motor Cortex,Premotor and Supplementary Motor Cortices,Anterior Central Gyrus,Gyrus Precentralis,Motor Area,Motor Strip,Precentral Gyrus,Precentral Motor Area,Precentral Motor Cortex,Premotor Area,Premotor Cortex,Primary Motor Area,Primary Motor Cortex,Secondary Motor Areas,Secondary Motor Cortex,Somatic Motor Areas,Somatomotor Areas,Supplementary Motor Area,Area 4, Brodmann,Area 4, Brodmann's,Area 6, Brodmann,Area 6, Brodmann's,Area, Motor,Area, Precentral Motor,Area, Premotor,Area, Primary Motor,Area, Secondary Motor,Area, Somatic Motor,Area, Somatomotor,Area, Supplementary Motor,Brodmann's Area 6s,Brodmanns Area 4,Brodmanns Area 6,Central Gyrus, Anterior,Cortex, Motor,Cortex, Precentral Motor,Cortex, Premotor,Cortex, Primary Motor,Cortex, Secondary Motor,Cortices, Secondary Motor,Gyrus, Anterior Central,Gyrus, Precentral,Motor Area, Precentral,Motor Area, Primary,Motor Area, Secondary,Motor Area, Somatic,Motor Areas,Motor Cortex, Precentral,Motor Cortex, Primary,Motor Cortex, Secondary,Motor Strips,Precentral Motor Areas,Precentral Motor Cortices,Premotor Areas,Primary Motor Areas,Primary Motor Cortices,Secondary Motor Area,Secondary Motor Cortices,Somatic Motor Area,Somatomotor Area,Supplementary Motor Areas
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D001732	Bite Force	The force applied by the masticatory muscles in dental occlusion.	Masticatory Force,Occlusal Force,Bite Forces,Force, Bite,Force, Masticatory,Force, Occlusal,Forces, Bite,Forces, Masticatory,Forces, Occlusal,Masticatory Forces,Occlusal Forces
D004525	Efferent Pathways	Nerve structures through which impulses are conducted from a nerve center toward a peripheral site. Such impulses are conducted via efferent neurons (NEURONS, EFFERENT), such as MOTOR NEURONS, autonomic neurons, and hypophyseal neurons.	Motor Pathways,Efferent Pathway,Pathway, Efferent,Pathways, Efferent