title: Measurement of lateral loads exerted on the maxillofacial region by habitual postures.
abstract: Lateral loads exerted on the maxillofacial region by habitual postures and habits may cause lateral shift or deformity of the mandible. These loads were measured with a desktop dynamic-strain gauge (DPM-600, Kyowa Co.) connected to a small, highly sensitive pressure sensor (PSL-A type, Kyowa Co.), and recorded with an oscillographic recorder (RDM-100A, Kyowa Co.). Measurements were taken with a pressure sensor embedded in silicone impression material placed in a vinyl chloride resin bag, on which pressures were applied. A preliminary study was conducted to obtain a proportional constant and a conversion formula for load calculation. The subsequent main study included 20 healthy male volunteers for load measurement in 12 positions. The mean load exerted on the mandible was 43.7 N when the subjects lay face down and approximately 20 N when they sat resting the lateral part of the chin on the hand, indicating that these loads are greater than regular orthodontic forces.
authors.affiliation: Suzaki Dental Clinic, 4-17-11 Nishifuna, Funabashi, Chiba 273-0031, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Suzaki
authors.forename: Miwako
authors.initials: M
authors.lastname: Naruse
authors.forename: Nobuko
authors.initials: N
authors.lastname: Watanabe
authors.forename: Hideharu
authors.initials: H
authors.lastname: Yamaguchi
mesh_terms: D000328:Adult; D001132:Arm / Q000502:physiology; D002610:Cheek / Q000502:physiology; D002680:Chin / Q000033:anatomy & histology / Q000502:physiology; D005145:Face / Q000033:anatomy & histology / Q000502:physiology*; D006184:Habits; D006225:Hand / Q000033:anatomy & histology; D006801:Humans; D008297:Male; D008334:Mandible / Q000502:physiology; D009991:Oscillometry / Q000295:instrumentation; D011187:Posture / Q000502:physiology; D016684:Prone Position / Q000502:physiology; D012828:Silicones; D014160:Transducers, Pressure; D016474:Weight-Bearing / Q000502:physiology*; D015050:Zygoma / Q000502:physiology
chemical_list: D012828:Silicones