Iida T, Kato M, Komiyama O, Suzuki H, Asano T, Kuroki T, Kaneda T, Svensson P, Kawara M
Department of Clinical Oral Physiology, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
Eur J Oral Sci. 2010 Dec;118(6):635-41. doi: 10.1111/j.1600-0722.2010.00784.x.
Using functional magnetic resonance imaging (fMRI), we compared the cerebral activity during bilateral light fist-clenching and light-teeth clenching to provide more information on the central processing mechanisms underlying awake bruxism. Fourteen subjects participated in our study. Statistical comparisons were used to identify brain regions with significant activation in the subtraction of light fist clenching and light teeth clenching activity minus baseline. Participants also evaluated the perceived effort of clenching for each task, using a visual analogue scale of 0-100, after fMRI was performed. Bilateral light fist-clenching significantly activated the bilateral sensorimotor cortex, while light teeth-clenching was significantly associated with activation of the bilateral sensorimotor cortex, supplementary motor area, dorsolateral prefrontal cortex, and posterior parietal cortex. The VAS scores for fist clenching and teeth clenching were not significantly different. As light teeth-clenching activates a more extensive cortical network compared with light fist-clenching, we suggest that the teeth clenching may induce a more complex cerebral activity compared with the performance of a hand motor task. The clinical significance of these findings remains unknown but could perhaps be related to the propensity to trigger awake bruxism.
我们使用功能磁共振成像（fMRI）比较了双侧轻度握拳和轻度咬牙时的大脑活动，以提供更多关于清醒磨牙症潜在中枢处理机制的信息。14名受试者参与了我们的研究。通过统计比较来确定在轻度握拳和轻度咬牙活动减去基线的差值中具有显著激活的脑区。在进行功能磁共振成像后，参与者还使用0至100的视觉模拟量表评估了每项任务中咬牙的主观用力程度。双侧轻度握拳显著激活了双侧感觉运动皮层，而轻度咬牙则与双侧感觉运动皮层、辅助运动区、背外侧前额叶皮层和顶叶后皮层的激活显著相关。握拳和咬牙的视觉模拟量表评分没有显著差异。由于与轻度握拳相比，轻度咬牙激活了更广泛的皮质网络，我们认为与手部运动任务相比，咬牙可能会诱发更复杂的大脑活动。这些发现的临床意义尚不清楚，但可能与引发清醒磨牙症的倾向有关。
