title: Biological-data-based finite-element stress analysis of mandibular bone with implant-supported overdenture.
abstract: BACKGROUND
  This study aimed to evaluate the stress distribution in a mandibular bone with an implant-supported overdenture by a biological-data-based finite element analysis (FEA) utilizing personal CT images and in vivo loading data, and to evaluate the influence of the number and alignment of implants and bone conditions on the stress in peri-implant bone.
  
  
  METHODS
  FEA models of a mandible were constructed for two types of overdentures: 4 implants supported overdenture (4-OD) and 2 implants supported overdenture (2-OD). The geometry of these models was constructed from CT images of a subject, who wore an implant-supported overdenture. The magnitude and direction of the loads on the implants for two types of overdentures during the maximal voluntary clenching were measured with 3D force transducers. FEA using these loads was carried out to observe stress distributions in peri-implant bone.
  
  
  RESULTS
  Higher stress was observed in cortical bone around the implant neck. Stress in peri-implant bone for 4-OD was reduced in comparison with those for the 2-OD. For the 4-OD, notwithstanding such reduction of the stress, the stress concentrated at the cortical bone around the implant aligned with large deviation from load direction.
  
  
  CONCLUSIONS
  In this study, biological data from a certain subject was successfully duplicated to the FEA models. The results demonstrate the mechanical prominence of using more implants. Even in 4 implants model, high stress was found around an implant with a large inclination and with thin cortical bone. This suffices to demonstrate the capability and usefulness of the biological-data-based FEA.
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan. Electronic address: shigemitsu@dent.tohoku.ac.jp.
authors.forename: Ryuji
authors.initials: R
authors.lastname: Shigemitsu
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yoda
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Ogawa
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Kawata
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Gunji
authors.affiliation: Department of Civil and Environmental Engineering, Tohoku University Graduate School of Engineering, Sendai 989-3204, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yamakawa
authors.affiliation: Department of Civil and Environmental Engineering, Tohoku University Graduate School of Engineering, Sendai 989-3204, Japan.
authors.forename: Kiyohiro
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Sasaki
mesh_terms: D019245:Compressive Strength / Q000502:physiology; D015921:Dental Implants; D017267:Dental Prosthesis Design; D003799:Dental Stress Analysis / Q000379:methods*; D003828:Denture, Overlay; D055119:Elastic Modulus / Q000502:physiology; D019544:Equipment Failure Analysis; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging* / Q000502:physiology* / Q000601:surgery; D008875:Middle Aged; D011859:Radiography; D013314:Stress, Mechanical; D016474:Weight-Bearing / Q000502:physiology*
chemical_list: D015921:Dental Implants
keywords: Biological data; Finite element method; Implant; Overdenture; Stress