RE MOUTH ACTIVITIES INVOLVED IN THE PROCESS OF COGNITIVE DISORDERS?-IN SEARCH OF NEUROPATHOLOGIC ASSOCIATIONS-

戴口罩被认为可以改善老年人的咀嚼能力、咀嚼舒适度和生活质量（QOL）。为了阐明义齿治疗对参与高级认知功能的前额叶皮层激活的影响，我们从认知和颌功能以及相关的前额叶皮层活动方面调查了戴义齿修复的疗效。部分无牙患者被招募为受试者。采用功能近红外光谱仪（f-NIRS）检测前额叶皮质区脑血流变化，采用问卷调查（SF 36 v2、OHIP-J、MMSE：简易精神状态检查）检测认知功能，同时检测颌肌肌电图和运动活动。咀嚼评分也被用来评估主观意识和咀嚼能力的意识。对戴和不戴义齿修复体时获得的数据进行统计学比较。咀嚼相关的颌骨功能，包括颌骨运动，颌骨肌肉肌电图，和前额叶皮层的活动显着增加，而咀嚼评分也显着改善戴局部义齿修复相比，非磨损条件。戴义齿引起的前额叶皮层活动与咀嚼评分和咀嚼肌电活动显著相关。在义齿修复过程中，患者的口腔、躯体生活质量及MMSE评分较治疗前均有改善趋势。根据我们的研究结果，我们认为，牙科治疗与义齿修复可能有助于改善不仅咀嚼颌功能，但也认知能力，如前额叶皮层激活和认知得分的口腔和身体生活质量。

Denture wearing is considered to improve chewing ability, chewing comfort, and quality of life(QOL) in elderly individuals. In order to clarify the effects of denture treatment on activation of the prefrontal cortex, which is involved in higher cognitive functions, we investigated the efficacy of wearing a denture prosthesis from the aspects of cognitive and jaw functions, and related prefrontal cortex activity. Partially edentulous patients were enlisted as subjects. Functional near infrared spectroscopy(f-NIRS) was used to detect changes of cerebral blood flow in the prefrontal cortex area, while cognitive functions were examined using questionnaires(SF36 v2, OHIP-J, and MMSE : Mini-mental state examination), with jaw muscle EMG and motions activities simultaneously investigated. Masticatory scores were also used to evaluate subjective awareness and consciousness of chewing ability. Statistical comparisons were performed between data obtained while wearing and not wearing a denture prosthesis. Significant increases were seen in chewing-related jaw functions, including jaw motion, jaw muscle EMG, and prefrontal cortex activity, while masticatory scores were also significantly improved by wearing a partial denture prosthesis as compared with the non-wearing condition. Prefrontal cortex activity caused by a wearing denture prosthesis was significantly related to masticatory score and masticatory EMG activities. During the process of denture treatment, the scores of dental and physical QOL, and MMSE showed improving trends as compared to the pre-therapeutic conditions. Based on our findings, we consider that dental treatment with a denture prosthesis may help to improve not only masticatory jaw functions, but also cognitive ability, as shown by prefrontal cortex activation and cognitive scores for oral and physical QOL.