title: The effect of platform switching on stress distribution in implants and periimplant bone studied by nonlinear finite element analysis.
abstract: BACKGROUND
  It is unknown whether dental implant systems with a platform-switched configuration have better periimplant bone stress distribution and lead to less periimplant bone level changes.
  
  
  OBJECTIVE
  The purpose of this study was to quantitatively investigate interfacial stress and stress distribution in implant bone in 2 implant abutment designs (platform-switched design and conventional diameter matching) by using a nonlinear finite element analysis method.
  
  
  METHODS
  A finite element simulation study was applied to 2 commercially available dental implant systems: the Ankylos implant system with a reduced-diameter abutment (platform-switched implant) and the Anthogyr implant system with an abutment of the same diameter (regular platform implant). These 2 dental implant systems were positioned in a bone block, which was constructed based on a cross-sectional image of a human mandible in the molar region. In simulation, a single vertical load of 50 N, 100 N, or 150 N and horizontal loads of 50 N and 100 N were applied to the occlusal surface of the abutment.
  
  
  RESULTS
  The finite element analysis found that the Ankylos implant system has a higher maximum von Mises stress in the implant abutment connection section and a lower maximum von Mises stress in the periimplant bone. The opposite results were found in the Anthogyr implant system.
  
  
  CONCLUSIONS
  Lower stress levels in the periimplant bone with a more uniform stress distribution were found for the Ankylos implant system with a platform-switched configuration. Although relatively higher stress was found in the abutment, premature implant failure is not anticipated because of the high strength of titanium alloy.
authors.affiliation: Postgraduate student, Institute of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Siyu
authors.initials: S
authors.lastname: Liu
authors.affiliation: Assistant Professor, Department of Dental Implantology, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China. Electronic address: cbtang@njmu.edu.cn.
authors.forename: Chunbo
authors.initials: C
authors.lastname: Tang
authors.affiliation: Assistant Professor, Department of Endodontology, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Yu
authors.affiliation: Postgraduate student, Institute of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Wenyong
authors.initials: W
authors.lastname: Dai
authors.affiliation: Assistant Professor, College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, China.
authors.forename: Yidong
authors.initials: Y
authors.lastname: Bao
authors.affiliation: Postgraduate student, College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Hu
mesh_terms: D001696:Biomechanical Phenomena; D001732:Bite Force; D000069343:Bone-Implant Interface / Q000502:physiology*; D003198:Computer Simulation; D017076:Computer-Aided Design; D003722:Dental Alloys / Q000737:chemistry; D003724:Dental Arch / Q000502:physiology; D059605:Dental Implant-Abutment Design; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008334:Mandible / Q000502:physiology; D008954:Models, Biological; D017711:Nonlinear Dynamics; D061848:Optical Imaging / Q000379:methods; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D003722:Dental Alloys; D015921:Dental Implants; D003764:Dental Materials; D014025:Titanium