title: In vivo measurement of the elastic modulus of the human periodontal ligament.
abstract: The present study was designated to determine the elastic properties of the periodontal ligament (PDL) in human subjects. A maxillary central incisor was experimentally translated so that stress or strain could be uniformly distributed in the PDL by applying a single force passing through the center of resistance. Displacements were measured under different magnitudes of load using a magnet-magnetic sensing system. From the load-displacement relations, Young's modulus of the PDL was calculated. The values determined were approximately 0.12 MPa under load ranging from 0 to 0.5 N, 0.25 MPa within the range of 0.5-1.0 N, 0.44 MPa under load 1.0-1.5 N, and between 0.69 and 0.96 MPa with 1.5-2.0 N. The values of Young's moduli increased almost exponentially with the increment of load due to a non-linear elasticity of the PDL.
authors.affiliation: Department of Orthodontics, Nagasaki University School of Dentistry, 1-7-1 Sakamoto Nagasaki 852-8588, Japan. nori@net.nagasaki-u.ac.jp
authors.forename: N
authors.initials: N
authors.lastname: Yoshida
authors.forename: Y
authors.initials: Y
authors.lastname: Koga
authors.forename: C L
authors.initials: CL
authors.lastname: Peng
authors.forename: E
authors.initials: E
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
mesh_terms: D000328:Adult; D004548:Elasticity; D005260:Female; D006801:Humans; D008280:Magnetics; D008953:Models, Anatomic; D009970:Orthodontics / Q000379:methods; D010513:Periodontal Ligament / Q000473:pathology / Q000502:physiology*; D013312:Stress, Physiological; D014070:Tooth / Q000033:anatomy & histology / Q000473:pathology