title: Stresses at the cervical lesion of maxillary premolar--a finite element investigation.
abstract: OBJECTIVE
  The objective of this study was to use a three-dimensional (3-D) finite element model to investigate normal stress distribution to substantiate the tooth flexure mechanism. The study also compared the changes in the stresses by different occlusal loading sites and directions.
  
  
  METHODS
  The 3-D finite element analysis was used. A maxillary premolar was selected to construct the simulation model. The model was constructed step-by-step for convergence and validity. Seven load conditions for various load sites and different directions were simulated to the model.
  
  
  RESULTS
  The maximal principal stress and minimal principal stress distributions developed within the structures of seven load conditions were output and their stress distributions on z-plane at the vertical midline were shown. The peak tensile stress of the cervical area for various load conditions were compared and listed.
  
  
  CONCLUSIONS
  This study has shown that the presence of tensile stresses in the cervical region of a maxillary premolar by various loading sites and different directions. The results coincided with the stress-induced theory, hence sustaining it. The relationship of the affected factors of leverage to the development of cervical abfraction lesions, was explored.
authors.affiliation: School of Dentistry, Kaohsiung Medical University, 100 Shih-Chuen 1st Road, Kaohsiung 80708, Taiwan.
authors.forename: H E
authors.initials: HE
authors.lastname: Lee
authors.forename: C L
authors.initials: CL
authors.lastname: Lin
authors.forename: C H
authors.initials: CH
authors.lastname: Wang
authors.forename: C H
authors.initials: CH
authors.lastname: Cheng
authors.forename: C H
authors.initials: CH
authors.lastname: Chang
mesh_terms: D001641:Bicuspid / Q000502:physiology; D001732:Bite Force; D003799:Dental Stress Analysis / Q000379:methods*; D020342:Finite Element Analysis; D006801:Humans; D008437:Maxilla; D008953:Models, Anatomic; D013314:Stress, Mechanical; D014072:Tooth Abrasion / Q000503:physiopathology; D019237:Tooth Cervix / Q000502:physiology*; D016388:Tooth Loss / Q000503:physiopathology