Effects of delayed-onset muscle soreness on masticatory function

The aim was to clarify the effects of experimentally provoked delayed-onset muscle soreness (DOMS) in the jaw-closing muscles on subjective and objective measures of masticatory function. Twenty-one dentate female subjects, without pain-related signs and symptoms of temporomandibular disorders, participated. Delayed-onset muscle soreness was provoked with eccentric and concentric contractions of the jaw-closing muscles using a custom-made apparatus. At baseline, and 24 h and 1 wk after the exercises, data were gathered on the subjective measures of muscle fatigue, muscle pain, and masticatory chewing ability using visual analogue scale (VAS) scores, on the maximum voluntary bite force (MVBF), and on the food Mixing Ability Index (MAI). After 24 h, muscle fatigue and muscle pain had increased and the MAI had decreased. All had returned to baseline levels after 1 wk. There were no significant changes found in the chewing ability VAS scores and in the MVBF over time. After correction for its baseline value, the MAI after 24 h was found to be significantly related to the muscle pain after 24 h. In conclusion, DOMS in the jaw-closing muscles can cause a decrease in the objectively scored chewing ability, while the subjectively scored chewing ability remained the same.