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Impact of Jaw-Sucking Movements on Postural Muscles Tension in Young Adults
Agnieszka Ptak1, Małgorzata Stefańska1
1Faculty of Physiotherapy, Wroclaw University of Health and Sport Science, al. Paderewskiego 35, 51-612 Wrocław, Poland.
Abstract:
Background: The objective of this study was to assess the tension of selected postural muscles during the jaw-sucking movement in four body positions (standing position, all-fours position, lying on front, lying on the side). Material and Methods: The research involved 30 young adults with an average age of 22.6 ± 0.72 years. Suprahyoid, trapezius, gluteus maximus, and gastrocnemius muscles were assessed in all study participants in the standing, kneeling, and belly lying positions (prone position). Measurements were taken twice for each position: once without jaw activity and once with jaw movements simulating sucking. Muscle function was determined by measuring muscle tension using surface electromyography (sEMG). Results: Engaging jaw movements in the prone position resulted in significantly increased tension in the gastrocnemius muscle. In the all-fours position, there was a notable rise in tension in both the gastrocnemius and gluteus maximus muscles. When standing, significantly higher tension was observed in the trapezius and gluteus maximus muscles. In contrast, the side-lying position exhibited no significant changes in muscle tension. Conclusions: The study's findings suggest that activating jaw function may affect the tone of the gastrocnemius muscle in both prone and quadrupedal positions. In contrast, there were no clear or statistically significant changes observed in the tone of trapezius muscles in either position, while, for the tension of the gluteus medius muscle, variability was shown only in the all-fours position.
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