2015 Volume 29 Issue 4 Pages 329-339
Oral health care has been focused on as one of the methods of prevention of a bedridden situation and rehabilitation in the elderly persons. Although some previous reports have demonstrated the association of cerebral activation with oral health care including tooth brushing, the effect of intra-oral brushing stimulation on prefrontal cerebral cortex activation has remained uncertain. In the present study, we examined the effect of intra-oral brushing on cerebral prefrontal cortex activation using near-infrared spectrography in 13 male young adult subjects (aged 19〜47 years, mean age 28.3±9.8 years). Brushing on the teeth, as well as gingival brushing, for 60 sec significantly increased blood flow levels in bilateral prefrontal cortex (PFC), compared to the control condition. In addition, the increase in PFC blood flow with intra-oral brushing was noticed in the left visceral lateral region of PFC (VL-PFC) and the working memory regions corresponded to the activated regions after a learning task such as frequent simple calculations for 60 sec. However, the increase of blood flow in these PFC regions with intra-oral brushing showed a lower level compared to those with a learning task as positive control. These findings suggest firstly that intra-oral brushing for oral health care may lead to an increase in blood flow in PFC, and secondly indicate that intra-oral stimulation may be applied as a useful method to enhance the neurocognitive function in elderly rehabilitation programs, and to prevent the bedridden situation via the neuronal activities in PFC.
