ABSTRACT
Objective To investigate stress and bone density distribution changes in the mandible due to the interference fit in titanium dental implants for mandible reconstruction, and study the influence of interference magnitudes on mandibular bone remodeling. Methods Eight interference fit models with titanium implants were established by finite element method. Bone remodeling based on strain energy density (SED) algorithm was employed to investigate changes in stress and bone density of the mandible in the models during 36 months with inference magnitude of 5%, 10%, 15%, 20%, 25%, 30%, 35% and 40%, respectively. Results When the diameter of pilot hole was larger than the internal diameter of titanium screw, the increment of interference magnitude would gradually enhance the screw fixation at the bone titanium dental implant interface. However, once the magnitude of interference exceeded 30%, the increase in interference magnitude might weaken the screw fixation due to the failure and loss of bone. Conclusions The diameter of pilot hole equal to or slightly smaller than the internal diameter of titanium screw is recommended for mandibular reconstruction.
ABSTRACT
Objective To create 3-D models of immediately loaded screw-type dental implants for finite element analysis by computer.Methods Using the commercial code of SolidWorks,3-D models of screw-type dental implants and a segment of mandibular bone were generated.By ABAQUS software,the 3-D implant-bone complex was meshed.The interfacial contact of bone and the implants was defined to be a frictional contact with the initial press-fit stress(by Interference Fit Option) to simulate the contact of immediately loaded implants and bone tissue.Results The finite element models of the immediately loaded screw-type implant were successfully created on the computer.As the interference fit got deeper,the interfacial initial press-fit stress got higher values.Conclusion The finite element models of the immediately loaded screw-type implants can be built with this method.The interfacial status of the primary press-fit stress can be simulated by the Interference Fit Options in the finite element software.