Hihara Hiroki, Kanetaka Hiroyasu, Kanno Akitake, Shimada Eriya, Koeda Satoko, Kawashima Ryuta, Nakasato Nobukazu, Sasaki Keiichi
Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Liaison Center for Innovative Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Heliyon. 2020 Jan 22;6(1):e03244. doi: 10.1016/j.heliyon.2020.e03244. eCollection 2020 Jan.
To evaluate the localization of responses to stimulation of the periodontal mechanoreceptors in the primary somatosensory cortex, somatosensory evoked fields (SEFs) were measured for stimulation of the left mandibular canine and first molar using magnetoencephalography in 25 healthy subjects. Tactile stimulation used a handmade stimulus device which recorded the trigger at the moment of touching the teeth.SEFs for the canine and first molar were detected in 20 and 19 subjects, respectively. Both responses were detected in the bilateral hemispheres. The latency for the canine was 62.1 ± 12.9 ms in the ipsilateral hemisphere and 65.9 ± 14.8 ms in the contralateral hemisphere. The latency for the first molar was 47.4 ± 6.6 ms in the ipsilateral hemisphere and 47.8 ± 9.1 ms in the contralateral hemisphere. The latency for the first molar was significantly shorter than that for the canine. The equivalent current dipoles were estimated in the central sulcus and localized anteroinferiorly compared to the locations for the SEFs for the median nerve. No significant differences in three-dimensional coordinates were found between the canine and first molar. These findings demonstrate the precise location of the teeth within the orofacial representation area in the primary somatosensory cortex.
为了评估在初级体感皮层中牙周机械感受器刺激反应的定位，在25名健康受试者中，使用脑磁图测量了左侧下颌尖牙和第一磨牙刺激时的体感诱发电场（SEF）。触觉刺激使用手工制作的刺激装置，该装置在接触牙齿的瞬间记录触发信号。分别在20名和19名受试者中检测到了尖牙和第一磨牙的SEF。双侧半球均检测到了两种反应。同侧半球中尖牙的潜伏期为62.1±12.9毫秒，对侧半球为65.9±14.8毫秒。第一磨牙同侧半球的潜伏期为47.4±6.6毫秒，对侧半球为47.8±9.1毫秒。第一磨牙的潜伏期明显短于尖牙。等效电流偶极在中央沟中估计，并且与正中神经SEF的位置相比位于前下方。尖牙和第一磨牙之间在三维坐标上没有发现显著差异。这些发现证明了牙齿在初级体感皮层口面部代表区内的精确位置。
