Three-Dimensional Finite Element Analysis of Mandibular Overdentures Supported by Mini-Implants
Abstract
This study examined the effect of using two anterior denture-supporting mini
implants (mIMP2) compared to four (two anterior and two posterior) denture-supporting
mini-implants (mIMP4) on the stress experienced by the mini-implants and the strain
experienced by the peri-implant and analogous posterior bone. The stress and strain values
were also compared to known values of strength for the mini-implants and physiologic strain
values. Finite element modeling was used to study the effects. Two models were created
identically, with the exception of the number of denture-supporting mini-implants used, and
contained modeled mucosa, cortical bone, cancellous bone, and the mini-implants. The
models were loaded over one second with three 70N loads bilaterally and results with
collected using a PostView program.
The anterior mini-implants in both models showed stresses that would not put them at
risk for fracture. The posterior mini-implants in mIMP4 experienced stresses above their
yield point, indicating that they could be at risk for fracture. Strain in the peri-implant bone
anteriorly and the posterior bone in mIMP2 was in the physiologic range. The posterior peri
implant bone in mIMP4 showed strains that were above physiologic, which indicates this
region could be at risk for bone resorption.
Based on the limitations of this study, posterior mini-implants and posterior peri
implant bone could be at risk for fracture and pathologic resorption. Dentists must weigh the
risks and benefits of using mini-implants to support overdentures in each clinical case to
determine if the treatment could be successful in light of the potential negative consequences.
Table of Contents
Introduction -- Materials and methods -- Results -- Discussion -- Conclusions.
Degree
M.S.