Myo-tronics Research, Inc., Seattle, Wash, USA.
J Prosthet Dent. 1975 Sep;34(3):245-53. doi: 10.1016/0022-3913(75)90100-6.
With the introduction of the Myo-Monitor to dentistry, the question has arisen whether the stimulus is neurally mediated or results from direct depolarization of only the fibers of the masseter muscle. Intensity-duration curves recorded for 10 subjects quantified the relationship between stimulus intensity and the duration of the stimulus required to elicit a consistent contraction response to transcutaneous stimulation via the Myo-Monitor. Individual chronaxies ranged from 0.125 to 0.180 msec., with a mean calculated at 0.158 msec. Stimulating the muscle fibers directly, without transmission of the signal across the neuromuscular junction, would have produced chronaxy values at least 50 to 100 times greater. The distinction is clear-cut. The chronaxy values unequivocally establish transmission of the stimulus across the neuromuscular junction. In all 10 subjects, contraction of muscles remote from the site of stimulation was evident by inspection and palpation. These data lend support to the conclusion of Choi and Mitani that the Myo-Monitor stimulates the fifth and seventh cranial nerves. The data derived here correlate with those of other investigations and clearly establish that the transmission of the Myo-Monitor stimulus is accomplished by transcutaneous neural stimulation.
随着 Myo-Monitor 在牙科中的引入，人们提出了这样一个问题，即刺激是通过神经介导的，还是仅仅导致咀嚼肌纤维的直接去极化。为 10 名受试者记录的强度-时间曲线量化了刺激强度与通过 Myo-Monitor 经皮刺激引起一致收缩反应所需的刺激持续时间之间的关系。个体时值范围为 0.125 至 0.180 毫秒，平均值计算为 0.158 毫秒。如果直接刺激肌肉纤维，而不通过神经肌肉接头传递信号，那么时值至少会增加 50 到 100 倍。区别很明显。时值明确地确立了刺激通过神经肌肉接头的传递。在所有 10 名受试者中，通过检查和触诊都可以明显看出远离刺激部位的肌肉收缩。这些数据支持 Choi 和 Mitani 的结论，即 Myo-Monitor 刺激第五和第七颅神经。这里得出的数据与其他研究的数据相关，明确确立了 Myo-Monitor 刺激的传递是通过经皮神经刺激来完成的。
