EVALUATION OF PRE-LOAD VARIATION EFFECTS ON THE STRESS BEHAVIOR IN DENTAL PROSTHESIS: FINITE ELEMENT STUDY
Bruno Agostinho Hernandez1; Alexander Paterno2; Gabriela Garcia Paschoeto1; João Paulo de Oliveira Freitas1; Edson A. Capello Sousa1
1 UNESP (Bauru); 2 UNESP( Bauru)
doi:10.20906/CPS/COB-2015-0219
Resumo
The Finite Element Method (FEM) allows the analysis of problems with complex geometries and loads, hard experimentation, besides non-linear situations. Due to that, it has been used on the analysis of biomechanical systems, such as in dental prosthesis. In this last case, the higher stresses, which occur in the crown, implant and bone interfaces, the cyclic loads and the misfit between crown and implant can lead to systems failure. The misfit usually happens due to a lower torque (pre-load) applied in the moment of system setting. Therefore, this work aims to analyze the effects of torque variation on the stress distribution in the set, especially in the screws. So, in order to do the analysis, a Finite Element Model was developed. The model was composed by a single implant, abutment, abutment's screw, crown, fix's screw and mandible bone. Three oblique loads, with 30º from vertical, were applied: 100 N, 200 N and 280 N. The loads variation is due to the fact the masticatory forces may vary. For each load, three different torques (pre-loads) were used for the abutment's screw: 200 N.mm, 100 N.mm and 50 N.mm. The results demonstrate for the 200 N and 280 N loads, the stresses in the abutment's screw were higher than the yield stress for the screw. For the torque, it was noted the direct influence of it in the stress distributions.
Palavras-chave: Finite Element Method; Dental prosthesis; Pre-load; Misfit