3D FEM Analysis of Tooth-Implant Prosthesis With Porcelain or Resin

Tooth intrusion in a tooth-implant partial fixed prosthesis with rigid connection is still a problem to be understood in dentistry. Vibration as result of dynamic oclusal load has been pointed to be responsible for osteoclatic activation with consequent tooth apical migration. The stiffness promoted by implants, in association to the high Young's Module of the materials must contribute to occurrence of vibration. Materials with lower values for Young's Module could absorb the mechanic energy, and dampen the vibration. Objectives: An experiment was made by means of 3D finite element method to evaluate a tooth-implant prosthesis with porcelain fused to metal placed in mandible.Methods:A dynamic load of 1N was applied at a frequency ranging from 0 to 0.55Hz at intervals of 0.05Hz. Afterwards, others of ceromer replaced the Poisson's ratio and Young's Module of porcelain and the same tests were applied under the same circumstances. Results:From the aspects of a qualitative analysis, vibration occurred in both situation, but significantly higher in the prosthesis with the esthetic with porcelain. In addition, a phenomenon of resonance, which is not desired under mechanical aspects, could be observed on the porcelain sample.Conclusions:When ceromer is employed in a tooth-implant fixed supported prosthesis with rigid connection instead of porcelain the structural rigidity is reduced, consequently lesser vibration is formed, and no resonance phenomenon is observed.Under the limits of the present experiment, we may conclude that such substitution may contribute to prevent tooth intrusion.