title: Factors affecting stresses in cortical bone around miniscrew implants: a three-dimensional finite element study.
abstract: OBJECTIVE
  To evaluate various types of stress in cortical bone around miniscrew implants using finite element analysis.
  
  
  METHODS
  Twenty-six three-dimensional assemblies of miniscrew models placed in alveolar bone blocks were constructed using Abaqus (Dassault Systèmes Simulia Corp, Providence, RI), a commercial finite element analysis software package. The model variables included implant design factors and bone-related factors. All miniscrew implants were loaded in the mesial direction with a linear force equal to 2 N. Peak von Mises and principal stress values in cortical bone were compared between the different models for each factor.
  
  
  RESULTS
  The results demonstrated that some factors affected the stresses in bone (implant diameter, implant head length, thread size, and elastic modulus of cancellous bone), while other factors did not (thread shape, thread pitch, and cortical bone thickness).
  
  
  CONCLUSIONS
  Miniscrew implant diameter, head length, and thread size as well as the elastic modulus of cancellous bone affect the stresses in cortical bone layer surrounding the miniscrew implant and may therefore affect its stability.
authors.affiliation: Department of Orthodontics, University of Illinois at Chicago, Chicago, IL 60612, USA.
authors.forename: Ramzi
authors.initials: R
authors.lastname: Duaibis
authors.forename: Budi
authors.initials: B
authors.lastname: Kusnoto
authors.forename: Raghu
authors.initials: R
authors.lastname: Natarajan
authors.forename: Linping
authors.initials: L
authors.lastname: Zhao
authors.forename: Carla
authors.initials: C
authors.lastname: Evans
mesh_terms: D001732:Bite Force; D001863:Bone Screws; D001842:Bone and Bones / Q000737:chemistry*; D003198:Computer Simulation; D015921:Dental Implants; D003799:Dental Stress Analysis / Q000379:methods*; D055119:Elastic Modulus; D004867:Equipment Design; D020342:Finite Element Analysis; D008422:Materials Testing; D003765:Models, Dental; D013314:Stress, Mechanical; D014025:Titanium / Q000737:chemistry*
chemical_list: D015921:Dental Implants; D014025:Titanium