Delayed‐onset muscle soreness in human masticatory muscles increases inhibitory jaw reflex responses

• Published in: Journal of oral rehabilitation Vol. 45; no. 6; pp. 430 - 435
• Main Authors: Koutris, M., Türker, K. S., Selms, M. K. A., Lobbezoo, F.
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01-06-2018
• Subjects: Adult; Analysis of Variance; Bite Force; Control charts; Data processing; Dentistry; Electromyography; Fatigue; Female; Healthy Volunteers; Humans; Jaw; Linear Models; Male; Mastication; Mastication - physiology; masticatory muscles; Masticatory Muscles - physiology; Motor task performance; Muscle Contraction - physiology; muscle contractions; Muscle fatigue; Muscle Fatigue - physiology; Muscles; myalgia; Myalgia - physiopathology; Pain; Pain Measurement; reflex; Reflexes; Time Factors; masticatory muscles; muscle contractions; myalgia; reflex; humans; muscle fatigue
• ISSN: 0305-182X; 1365-2842
• DOI: 10.1111/joor.12635

Summary
The effects of masticatory muscles’ overloading on jaw‐motor control are not yet fully clarified. Therefore, it was tested whether eccentric and concentric exercises of the human masticatory muscles would influence inhibitory jaw reflex responses. Eleven participants (6 males, 5 females) performed 6, 5‐minutes bouts of eccentric‐concentric contractions. Before, immediately after, 24 hours, 48 hours and 1 week afterwards, visual analogue scale (VAS) scores for jaw muscle fatigue and pain, maximum voluntary bite force (MVBF) and inhibitory jaw reflexes were recorded. Reflex data were analysed with the cumulative sum control chart error box method. Immediate and delayed masticatory muscle fatigue and pain were provoked. Further, 24 hours after the exercises, MVBF tended to decrease (P = .056), suggesting that delayed‐onset muscle soreness (DOMS) was provoked in the masticatory muscles. In addition, the inhibitory jaw reflex showed a delayed increase in size 24 hours after the exercise (P < .05). In conclusion, DOMS provoked in the masticatory muscles alters jaw motor control by inducing a delayed increase in the size of the inhibitory jaw reflex.