|
KMID : 1004520120280020147
|
|
Journal of Dental Rehabilitation and Applied Science
2012 Volume.28 No. 2 p.147 ~ p.161
|
|
|
Finite Element Analysis of Bone Stress Caused by Horizontal Misfit of Implant Supported Three-Unit Fixed Prosthodontics
|
|
Lee Seung-Hwan
Jo Kwang-Hun
|
|
|
Abstract
|
|
|
This study is to assess the effect of horizontal misfit of an implant supported 3-unit fixed prosthodontics on the stress
development at the marginal cortical bone surrounding implant neck. Two finite element models consisting of a three unit
fixed prosthodontics and an implant/bone complex were constructed on a three dimensional basis. The three unit fixed
prosthodontics were designed either shorter (d=17.8mm model) or longer (d=18.0mm model) by 0.1mm than the span of
two implants placed at the mandibular second premolar and second molar areas 17.9mm apart. Fitting of the fixed
prosthodontics onto the implant abutments was simulated by a total of 6 steps, that is to say, 0.1mm displacement per
each step, using DEFORM 3D (ver 6.1, SFTC, Columbus, OH, USA) program. Stresses in the fixed prosthodontics and
implants were evaluated using von-Mises stress, maximum compressive stress, and radial stress as necessary. The
d=17.8mm model assembled successfully on to the implant abutments while d=18.0mm model did not. Regardless if the
fixed prosthodontics fitted onto the abutments or not, excessively higher stresses developed during the course of assembly trial and thereafter. On the marginal cortical bone around implants during the assembly, the peak tensile and compressive stresses were as high as 186.9MPa and 114.1MPa, respectively, even after the final sitting of the fixed prosthodontics (for d=17.8mm model). For this case, the area of marginal bone subject to compressive stresses above 55MPa, equivalent of the 4,000με, i.e. the reported threshold strain to inhibit physiological remodeling of human cortical bone, extended up to 2mm away from implant during the assembly. Horizontal misfit of 0.1mm can produce excessively high stresses on the marginal cortical bone not only during the fixed prosthodontics assembly but also thereafter.
|
|
|
KEYWORD
|
|
|
Finite Element Analysis, Horizontal Misfit, Implant Supported Fixed Prosthodontics
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
|
|