title: Experimental evaluation of initial tooth displacement, center of resistance, and center of rotation under the influence of an orthodontic force.
abstract: The purpose of this study was to determine the location of the center of resistance and the center of rotation of the maxillary central incisors under the influence of a single simple force and to investigate related geometric parameters of the teeth and the surrounding periodontal tissues. By measuring the initial displacement of the central incisors with a magnetic sensing system, the location of the center of resistance and the centers of rotation associated with various forces were determined in 3 human subjects. The results show that the location of the center of resistance of the maxillary central incisor depends on the palatal bone level and is at approximately two-thirds of the palatal alveolar bone height, measured from the root apex. A greater moment-to-force ratio is needed for any controlled movement of the maxillary incisors during retraction in patients with reduced palatal alveolar bone height. This study suggests a method for estimating the location of the center of resistance of a tooth.
authors.affiliation: Department of Orthodontics, Nagasaki University School of Dentistry, Japan. nori@net.nagasaki-u.ac.jp
authors.forename: N
authors.initials: N
authors.lastname: Yoshida
authors.forename: P G
authors.initials: PG
authors.lastname: Jost-Brinkmann
authors.forename: Y
authors.initials: Y
authors.lastname: Koga
authors.forename: N
authors.initials: N
authors.lastname: Mimaki
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
mesh_terms: D016301:Alveolar Bone Loss / Q000503:physiopathology; D001696:Biomechanical Phenomena; D003799:Dental Stress Analysis; D006801:Humans; D007180:Incisor / Q000502:physiology* / Q000503:physiopathology*; D008310:Malocclusion / Q000503:physiopathology; D008437:Maxilla; D012399:Rotation; D012815:Signal Processing, Computer-Assisted; D014087:Tooth Movement Techniques