Anterior and posterior neck muscle activation during a variety of biting tasks

Abstract

Bruxism may be involved in the aetiology of myofascial neck pain. The objective of this study was to test the hypothesis that anterior and posterior neck muscles co-contract during jaw clenching. Ten test subjects developed different feedback-controlled submaximum bite forces in a variety of bite-force directions by means of bite-force transducers. The electromyographic activity of the sternocleidomastoid and supra/infrahyoidal muscles, and of the semispinalis capitis, semispinalis cervicis, and multifidi muscles was recorded by use of surface electrodes and intramuscular wire electrodes, respectively. For normalization of electromyography data, maximum voluntary contraction tasks of the neck muscles were conducted in eight different loading directions. The results confirmed co-contraction of the neck muscles in the range of 2-14% of the maximum voluntary contraction at a bite force ranging from 50 to 300 N. Significant activity differences were observed as a result of the different force levels and force directions exerted by the jaw muscles. Long-lasting tonic activation of specific neck muscles triggered by the jaw-clenching tasks was also detected. These findings support the assumption of a relationship between jaw clenching and the activity of the neck muscles investigated. The low level of co-contraction activity, however, requires further study to elucidate possible pathophysiological interactions at the level of single motor units.

Co‐contraction behaviour of masticatory and neck muscles during tooth grinding

“…Recent intramuscular EMG studies have shown that, for an upright body position, individual superficial and deep neck muscles co‐contract at 10% to 15% of their maximum voluntary contraction (MVC) during a variety of controlled jaw‐clenching tasks at submaximum force (ranging from 50 to 300 N) . This activation level corresponds well to those found during mastication.…”

“…This activation level corresponds well to those found during mastication. Another interesting finding for several neck muscles is the occurrence of low‐level, long‐lasting tonic activation (LLTA) which outlasts the specific submaximum motor tasks . LLTA of motor units (also known as Cinderella units) has been observed in previous studies of neck muscles, and it has been hypothesised they might be a source of muscle lesions or fatigue in neck pain patients .…”

Does altered mandibular position and dental occlusion influence upper cervical movement: A cross–sectional study in asymptomatic people

“…In humans, Wang et al (2004) reported increased cervical muscle EMG recorded from sternocleidomastoid muscles following noxious injection into the masseter muscle. Evidence of this inter-relationship is also seen by increased activation of both anterior and posterior superficial, and deep cervical muscles during maximal and submaximal clenching (Lodetti et al, 2012;Hellmann et al, 2012;Giannakopoulos et al, 2013a;2013b). Based on this evidence, reduction in upper cervical mobility may be explained by activation of masticatory (Torisu et al, 2007;Manfredini et al, 2013) as well as cervical muscles during conscious teeth contact (Giannakopoulos et al, 2013b).…”

“…Increased anterior and posterior superficial, and deep neck muscle activity has been recorded during conscious teeth clenching (Hellmann et al, 2012 ;Giannakopoulos et al, 2013a;Giannakopoulos et al, 2013b).…”

Effects of intervertebral disc disorders of low back on the mandibular kinematic: kinesiographic study

“…This leads a variety of neuromuscular interactions, for instance, synchronized extension–flexion movements of the head during jaw-opening/closing cycles [7]. …”