MECHANORECEPTORS AROUND THE TOOTH EVOKE INHIBITORY AND EXCITATORY REFLEXES IN THE HUMAN MASSETER MUSCLE
MECHANORECEPTORS AROUND THE TOOTH EVOKE INHIBITORY AND EXCITATORY REFLEXES IN THE HUMAN MASSETER MUSCLE
复制标题
DOI：
10.1113/jphysiol.1993.sp019659
复制
发表时间：
1993-05-01
影响因子：
5.5
通讯作者：
MILES, TS
中科院分区：
文献类型：
--
作者：
BRODIN, P;TURKER, KS;MILES, TS
1.本文用肌电方法研究了机械刺激人切牙引起的咬肌反射反应。刺激为（缓慢）推和（快速）敲，峰值力约为0-5-3 N，垂直于唇面施加。如前所述，轻快的敲击引起短潜伏期的抑制反射，随后通常是兴奋性峰值。抑制作用随敲击强度的增加而增强.慢推诱发长潜伏期，主要是兴奋性反应。随着上升时间的增加，刺激的强度增加，但随着刺激强度的增加，短潜伏期的抑制反应往往在兴奋开始前就已明显.当用局部麻醉剂阻断牙齿周围的感受器时，对3 N推压和2N敲击的反射反应被消除，表明该反应是由位于牙周区域内的感受器引起的.长时间的快速位移引起了一种复杂的反射反应，这种反应结合了轻拍和推动的特点。推和敲引起的不同反应的最可能的解释是，由慢速和快速牙齿位移引起的传入活动模式激活了不同的运动神经元间通路。对叩击的抑制反应本质上是一种保护性反射，当一个人意外地咬硬物时，这种反射可能会减少下颌闭合肌肉的活动。这表明，兴奋性反应可能有助于肌肉活动所需的牙齿之间的食物在咀嚼，或可能作为一个负荷补偿反射，以控制咀嚼力。
1. The reflex responses evoked in the human masseter muscle by controlled mechanical stimulation of an incisor tooth were examined electromyographically. The stimuli were (slow) pushes and (brisk) taps of about 0-5-3 N peak force, applied orthogonally to the labial surface.2. The brisk taps elicited a short-latency inhibitory reflex that was often followed by an excitatory peak, as has been described earlier. The inhibition increased as the taps became stronger.3. Slow pushes evoked a long-latency, primarily excitatory response. The excitation increased with stronger, faster rise-time pushes; however, with the stronger stimuli, the short-latency inhibitory response often became evident before the onset of the excitation.4. The reflex responses to 3 N pushes and 2 N taps were abolished when the receptors around the tooth were blocked with local anaesthetic, indicating that the response was elicited from receptors located within the periodontal area.5. Prolonged, rapid-onset displacements evoked a complex reflex response that combined the characteristics of the taps and the pushes.6. The most likely explanation for the different responses evoked by the pushes and taps is that the patterns of afferent activity elicited by the slow and fast tooth displacements activated different interneuronal pathways to motoneurones.7. The inhibitory response to taps is essentially a protective reflex which probably serves to reduce the activity of the jaw-closing muscles when one bites unexpectedly on hard objects. It is suggested that the excitatory response may contribute to the muscle activity required to hold food between the teeth during chewing, or may act as a load compensation reflex to control chewing force.