title: Multiscale analysis of stress distribution in teeth under applied forces.
abstract: OBJECTIVE
  The present study aimed to clarify stress distribution in teeth under an external applied load using microindentation and multiscale simulation.
  
  
  METHODS
  Anisotropic material properties of enamel and dentin were measured using a microindentation method with a dynamic ultra microhardness tester. The numerical model was constructed using the finite element mesh superposition method with a microscale (enamel rods), mesoscale (teeth), and macroscale (bone). Multiscale simulation was used to analyze different scale structures. A concentrated load (10 N) was applied to the labial surface of the central incisor.
  
  
  RESULTS
  The results revealed stresses of 5 MPa (normal stress) and 6.5 MPa (shear stress) in the enamel sheath at the center of the labial region compared to 1.4 MPa (normal stress) and 21.4 MPa (shear stress) in the cervical region.
  
  
  CONCLUSIONS
  These results suggest that shear stresses in the enamel sheath may play significant roles in stress transmission.
authors.affiliation: Division for Interdisciplinary Dentistry, Osaka University School of Dentistry, Suita, Osaka, Japan. miura_j@dent.osaka-u.ac.jp <miura_j@dent.osaka-u.ac.jp>
authors.forename: Jiro
authors.initials: J
authors.lastname: Miura
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Maeda
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nakai
authors.forename: Masaru
authors.initials: M
authors.lastname: Zako
mesh_terms: D000539:Alveolar Process / Q000502:physiology; D016880:Anisotropy; D003198:Computer Simulation; D003481:Cuspid / Q000502:physiology; D003743:Dental Enamel / Q000502:physiology*; D003799:Dental Stress Analysis; D003804:Dentin / Q000502:physiology*; D055119:Elastic Modulus; D020342:Finite Element Analysis; D006244:Hardness; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007180:Incisor / Q000502:physiology; D008954:Models, Biological; D010513:Periodontal Ligament / Q000502:physiology; D013314:Stress, Mechanical; D014070:Tooth / Q000502:physiology*; D019237:Tooth Cervix / Q000502:physiology