title: Bivariate evaluation of cylinder implant diameter and length: a three-dimensional finite element analysis.
abstract: OBJECTIVE
  To evaluate continuous and simultaneous variations of implant diameter and length for an experimental cylinder implant.
  
  
  METHODS
  A finite element model of a mandible segment with implant was created. The range of implant diameter (D) was set from 2.5 to 5.0 mm, and that of implant length (L) from 6.0 to 16.0 mm. The maximum Von Mises stresses in the mandible were evaluated, and the sensitivity of the stresses in the mandible to the variables was also evaluated.
  
  
  RESULTS
  Under axial load, the maximum von Mises stresses in cortical and cancellous bones decreased by 73.3% and 69.4%, respectively, with D and L increasing. Under buccolingual load, those decreased 83.8% and 79.2%, respectively. When D exceeded 3.9 mm and L exceeded 10.0 mm, the tangent slope rate of the maximum von Mises stress response curve ranged from -1 to 0. The variation of the maximum von Mises stresses in the mandible was more sensitive to D than to L.
  
  
  CONCLUSIONS
  Buccolingual force is apt to be influenced by the two implant parameters; implant diameter and length favor stress distribution in cortical bone and cancellous bone, respectively. Implant diameter exceeding 3.9 mm and implant length exceeding 10.0 mm are the optimal choice for type B/2 bone in a cylinder implant. The implant diameter is more important than length in reducing bone stress.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Stomatology, the Fourth Military Medical University, Xi'an, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Kong
authors.forename: Yingying
authors.initials: Y
authors.lastname: Sun
authors.forename: Kaijin
authors.initials: K
authors.lastname: Hu
authors.forename: Dehua
authors.initials: D
authors.lastname: Li
authors.forename: Rui
authors.initials: R
authors.lastname: Hou
authors.forename: Jin
authors.initials: J
authors.lastname: Yang
authors.forename: Baolin
authors.initials: B
authors.lastname: Liu
mesh_terms: D003198:Computer Simulation; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D003776:Dental Porcelain / Q000737:chemistry; D017267:Dental Prosthesis Design; D004548:Elasticity; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008334:Mandible / Q000502:physiology; D008422:Materials Testing; D008954:Models, Biological; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D015921:Dental Implants; D003764:Dental Materials; D003776:Dental Porcelain; D014025:Titanium