<p>The purpose of this study was to clarify the relationship between the periodontal tactile sensation and the activity of the prefrontal cortex. Eleven young, healthy Japanese participants (mean age 28.0±3.7 years) volunteered to participate in this study. We tested either the left side central incisors or the first molars. The periodontal tactile sensation of each tooth was evaluated using calibrated monofilaments (von Frey hairs). A magnitude estimation method was used as a psychophysical method, and the periodontal ligament tactile and periodontal tactile sensation values were determined by Stevens’ power law. Prefrontal cortex activation was evaluated using a wearable functional near-infrared spectroscopy device that measured cerebral blood flow, and the experimental task involved maintaining occlusal force within an instructed range. The logarithmic values of the physical and sensory quantities of periodontal tactile sensation showed a linear relationship, and had a significantly high correlation coefficient. Regarding the periodontal tactile sensation values, no significant difference was found between the central incisors and first molars. In the molar teeth, negative correlations were found between the periodontal tactile sensation values and the cerebral blood flow in all measurement fields. Moreover, the mean occlusal force value of molars was below the instructed range, and showed significantly lower values compared to those of anterior teeth. Based on the above results, it was shown that Stevens’ power law can be applied to periodontal tactile sensation, and the periodontal tactile sensation value in molars calculated from Stevens’ power law is related to the cerebral blood flow in the prefrontal cortex and inhibition of occlusal force. The site-specific importance of the periodontal tactile sensation value was suggested during the task of maintaining occlusal force.</p>