title: Effects of mandibular retrusive deviation on prefrontal cortex activation: a functional near-infrared spectroscopy study.
abstract: The objective of this study was to evaluate occlusal condition by assessing brain activity in the prefrontal cortex, which is associated with emotion. Functional near-infrared spectroscopy (fNIRS) was used to detect changes in cerebral blood flow in the prefrontal cortex of 12 healthy volunteers. The malocclusion model was a custom-made splint that forced the mandible into retrusion. A splint with no modification was used as a control. The cortical activation during clenching was compared between the retrusive position condition and the control condition. A visual analog scale score for discomfort was also obtained during clenching and used to evaluate the interaction between fNIRS data and psychiatric changes. Activation of the prefrontal cortex was significantly greater during clenching in the mandibular retrusive condition than during clenching in the control condition. Furthermore, Spearman rank-correlation coefficient revealed a parallel relation between prefrontal cortex activation and visual analog scale score for discomfort. These results indicate that fNIRS can be used to objectively evaluate the occlusal condition by evaluating activity in the prefrontal cortex.
authors.affiliation: Orthodontic Division, Department of Oral Science, Kanagawa Dental University Graduate School, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Takero
authors.initials: T
authors.lastname: Otsuka
authors.affiliation: Orthodontic Division, Department of Oral Science, Kanagawa Dental University Graduate School, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Yamasaki
authors.affiliation: Orthodontic Division, Department of Oral Science, Kanagawa Dental University Graduate School, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Tateshi
authors.initials: T
authors.lastname: Shimazaki
authors.affiliation: Photomedical Dentistry Division, Department of Oral Science, Kanagawa Dental University Graduate School, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Fumihiko
authors.identifier: 0000-0001-6068-6268
authors.initials: F
authors.lastname: Yoshino
authors.affiliation: Orthodontic Division, Department of Oral Science, Kanagawa Dental University Graduate School, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sasaguri
authors.affiliation: Orthodontic Division, Department of Oral Science, Kanagawa Dental University Graduate School, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Toshitsugu
authors.initials: T
authors.lastname: Kawata
mesh_terms: D000328:Adult; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D008297:Male; D017397:Prefrontal Cortex / Q000098:blood supply* / Q000503:physiopathology*; D063173:Retrognathia / Q000503:physiopathology*; D013055:Spectrophotometry, Infrared