Chewing-related prefrontal cortex activation while wearing partial denture prosthesis: Pilot study

Abstract

From the standpoint of dental medicine, denture wearing is considered to improve chewing ability, chewing comfort, and quality of life in elderly individuals. We attempted to clarify the effects of prosthodontic treatment on activation of the dorsal prefrontal cortex, which is involved in higher cognitive functions. Three partially edentulous patients, one 60-year-old male, and two females, 57 and 64 years old, were enlisted as subjects. For detection of changes in cerebral blood flow, near infrared spectroscopy (NIRS) was used. EMG recording was also conducted to detect bilateral activities of the masseter muscles (Mm). Significant activation of the dorsal prefrontal cortex in the right and/or left hemisphere was shown while wearing partial denture prosthesis. Furthermore, Mm EMG activity was significantly increased while wearing a partial denture prosthesis. We concluded that a partial dental prosthesis significantly stimulates both masticatory muscle and dorsal prefrontal cortex activities, which might contribute to the prevention of cognitive impairment in aged individuals.