title: Influence of bone parameters on peri-implant bone strain distribution in the posterior mandible.
abstract: OBJECTIVE
  The success rate of dental implants depends on the type of bone at the implant site. The purpose of the present study was to investigate the effects of the bone parameters at the implant-placement site on peri-implant bone strain distributions.
  
  
  METHODS
  The morphologies and bone densities of seventy-five potential implant sites in the posterior mandible were measured using computed tomography (CT). Based on the CT data, we defined bone parameters (low and high in terms of cancellous-bone density and crestal-cortical bone density, and thin and thick in terms of crestal-cortical bone thickness), and we constructed finite-element models simulating the various bone types. A buccolingual oblique load of 200 N was applied to the top of the abutment. The von Mises equivalent (EQV) strains in the crestal-cortical bone and in the cancellous bone around the implant were calculated.
  
  
  RESULTS
  Cancellous-bone density greatly affected the maximum EQV strain regardless of the density and thickness of the crestal cortical-bone. The maximum EQV strains in the crestal cortical-bone and the cancellous bone in the low-density cancellous-bone models (of 150 Hounsfield units (HU)) were 1.56 to 2.62-fold and 3.49 to 5.31-fold higher than those in the high-density cancellous-bone models (of 850 HU), respectively. The crestal cortical-bone density affected the maximum EQV strains in the crestal cortical-bone and in the cancellous bone in the low-density cancellous-bone models. The crestal cortical-bone thickness affected the maximum EQV strains in the cancellous bone and in the crestal cortical-bone in the low-density cancellous-bone models.
  
  
  CONCLUSIONS
  Our results confirm the importance of bone types for the peri-implant bone strain distribution. Cancellous-bone density may be a critical factor for peri-implant bone strain.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Nara Medical University, 840 Shijo-cho, Kashihara City, Nara 634-8522, Japan, sugiurat@naramed-u.ac.jp.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sugiura
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawakami
authors.forename: Satoshi
authors.initials: S
authors.lastname: Horita
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Murakami
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Kirita
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D015921:Dental Implants; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D008875:Middle Aged; D014057:Tomography, X-Ray Computed
chemical_list: D015921:Dental Implants