Department of Clinical Oral Physiology, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho-nishi, Matsudo, Chiba 271-8587, Japan.
Clin Neurophysiol. 2010 May;121(5):793-9. doi: 10.1016/j.clinph.2010.01.009. Epub 2010 Feb 12.
The present study compared the perception of electric and magnetic stimuli for reflex appearance threshold (RT) and reflex saturation threshold (RS) of the exteroceptive suppression reflex (ES) in the masseter muscle.
Twelve healthy males and 12 females (age: 24.2+/-3.2 years) participated. The surface EMG was recorded from the left masseter muscle. The stimulus intensities were set as multiple values of the sensory threshold (ST), and were applied to the skin above the left mental nerve. Subjects reported the perceived intensity of the stimulus on a numeric rating scale (NRS) at RT and RS for the early and late ES (ES1 and ES2, respectively).
ES2 had a lower RT and RS compared to ES1 in electric and magnetic stimulation. Significantly lower NRS values at RT and RS were found with painless magnetic stimulation compared to electric stimulation (p<0.01).
In contrast to electrical stimulation, both ES1 and ES2 appeared and saturated with painless magnetic stimuli.
The present results indicate that both ES1 and ES2 have a non-nociceptive origin. Painless magnetic stimuli will be an advantage in ES reflex examinations for various orofacial pain conditions.
本研究比较了电刺激和磁刺激在外感受抑制反射（ES）中对咀嚼肌反射出现阈（RT）和反射饱和阈（RS）的感知。
12 名健康男性和 12 名女性（年龄：24.2±3.2 岁）参与了研究。表面肌电图（EMG）记录来自左侧咀嚼肌。刺激强度设定为感觉阈（ST）的多个值，并施加到左侧颏神经上方的皮肤。受试者在 RT 和 RS 时使用数字评分量表（NRS）报告对 ES1 和 ES2（分别为 ES1 和 ES2）的早期和晚期 ES 感知到的刺激强度。
与电刺激相比，磁刺激在 ES2 时具有更低的 RT 和 RS。与电刺激相比，无痛磁刺激在 RT 和 RS 时的 NRS 值明显更低（p<0.01）。
与电刺激相反，无痛磁刺激既可以引发 ES1，也可以引发 ES2。无痛磁刺激将成为各种口腔颌面部疼痛病症 ES 反射检查的优势。
本研究结果表明 ES1 和 ES2 均具有非伤害性起源。无痛磁刺激将成为各种口腔颌面部疼痛病症 ES 反射检查的优势。
