Effects of masticatory muscle fatigue without and with experimental pain on jaw-stretch reflexes in healthy men and women

摘要: Abstract Objective To examine the effects of experimentally evoked masticatory muscle fatigue, without and with experimental pain, on short-latency jaw-stretch reflex, using a randomised crossover design. Methods Reflexes were in both masseter temporalis muscles 15 men 13 women. The study was performed two blocks, containing 3 conditions (before, directly after, 15 min after provocation). Provocation consisted fatiguing chewing test, followed by an intramuscular injection either isotonic saline (IS; non-painful) or hypertonic (HS; painful). Results No significant condition ‘fatigue+IS’ found for any reflex outcome variables. For each muscle, ‘fatigue+HS’ yielded significantly higher normalized amplitudes than other conditions. Several displayed gender differences regarding onset latency amplitude. Conclusions Experimentally mild-to-moderate fatigue does not modulate human reflex. On hand, performance yield facilitation this peak-to-peak amplitude stress need to take into consideration future jaw studies. Significance sensitivity can be modulated HS-induced pain; that is provoked intense chewing.