title: A review of improved fixation methods for dental implants. Part II: biomechanical integrity at bone-implant interface.
abstract: OBJECTIVE
  The purpose of this article is to review the mechanical requirements of the tissue-implant interface and analyze related theories.
  
  
  METHODS
  The osseointegration capacity of titanium implants has been investigated over the past 50 years. We considered the ultimate goal of osseointegration to which form a desirable interfacial layer and a bone matrix with adequate biomechanical properties.
  
  
  RESULTS
  Occasionally, the interface comprises porous titanium and bone ingrowth that enables a functionally graded Young's modulus, thereby allowing reduction of stress shielding. However, the optimal biomechanical connection at the interface has not yet been fully clarified. There have been publications supporting several universal mechanical testing technologies in terms of bone-titanium bonding ability, although the separation of newly formed bone quality is unlikely.
  
  
  CONCLUSIONS
  The understanding of complex mechanical bone behavior and size-dependent properties ranging from a nano- to a macroscopic level are essential in the biomechanical optimization of implants. The requirements of regenerated tissue at the interface include high strength, fracture toughness related to ductility, and time-dependent energy dissipation and/or elastic-plastic stress distribution. Moreover, a strong relationship between strain signals and peri-implant tissue turnover could be expected, so that ideal implant biomechanics may enable longevity via adaptive bone remodeling.
authors: Department of Conservative Dentistry, Division of Biomaterials & Engineering, Showa University School of Dentistry, Tokyo, Japan. Electronic address: yookun@dent.showa-u.ac.jp.
authors: Yo
authors: Y
authors: Shibata
authors: Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
authors: Yasuhiro
authors: Y
authors: Tanimoto
authors: Department of Orthodontics, Showa University School of Dentistry, Tokyo, Japan.
authors: Noriko
authors: N
authors: Maruyama
authors: Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
authors: Manamu
authors: M
authors: Nagakura
mesh_terms: D001696:Biomechanical Phenomena; D001861:Bone Regeneration / Q000502:physiology*; D016723:Bone Remodeling / Q000502:physiology; D001842:Bone and Bones / Q000502:physiology*; D000069343:Bone-Implant Interface / Q000502:physiology*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D055119:Elastic Modulus; D020342:Finite Element Analysis; D006801:Humans; D016348:Osseointegration / Q000502:physiology*; D014025:Titanium
chemical_list: D015921:Dental Implants; D014025:Titanium
keywords: Finite element analysis; Mechanical properties; Osseointegration; Titanium implant