title: Effects of experimentally deviated mandibular position on stress response.
abstract: The purpose of this study was to investigate the effects of stress on -prefrontal cortex (PFC), emotion (using visual analogue scale, VAS, and State-Trait Anxiety Inventory, STAI), and the autonomic nervous system (ANS). Two types of stress were applied: (1) malocclusion-induced physical stress and (2) mental stress induced by an arithmetic task. Malocclusion was induced using an experimentally deviated mandibular device (EDMD) to obtain an experimentally deviated mandibular position (EDMP). A total of 11 healthy volunteers participated in the study. On day 1 they performed a pretrial arithmetic task followed by a 10-min rest, after which they performed a posttrial EDMD + arithmetic task or rest device + arithmetic task. These two tasks were selected at random and assigned at the rate of one per day. Activity in the PFC tended to show an increase in the pretrial arithmetic tasks and rest device + arithmetic task, but a decrease in the EDMD + arithmetic task compared with the rest device + arithmetic task. Heart rate significantly increased during the rest device + arithmetic task, whereas no significant difference was observed during the EDMD + arithmetic task. The EDMD + arithmetic task significantly increased STAI scores (p = 0.0047), and the significant decrease in VAS indicated "unpleasant" (p = 0.035). These findings suggest that EDMP-induced reduction in the level of PFC activity was a response to discomfort, indicating that EDMP affects systemic function such as that of the ANS as an unpleasant stressor.
authors.affiliation: Department of Sports Dentistry, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba, 261-8502, Japan. aamemiya@tdc.ac.jp.
authors.forename: Ai
authors.initials: A
authors.lastname: Amemiya
authors.affiliation: Department of Sports Dentistry, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba, 261-8502, Japan.
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Takeda
authors.affiliation: Department of Sports Dentistry, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba, 261-8502, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Nakajima
authors.affiliation: Department of Sports Dentistry, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba, 261-8502, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ishigami
authors.affiliation: Division of Optical Brain Engineering, Department of Neurosurgery, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Tsujii
authors.affiliation: Division of Optical Brain Engineering, Department of Neurosurgery, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sakatani
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008334:Mandible / Q000503:physiopathology*; D008433:Mathematics; D008606:Mental Processes / Q000502:physiology*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D012146:Rest; D013315:Stress, Psychological / Q000209:etiology*; D055815:Young Adult