A Finite element analysis of stress distribution in all on four system using different framework materials in the mandible

Abstract

Statement of the problem: The all on four immediate function approach rehabilitating mandibular arch is a successful rout of treatment for resorbed ridges that otherwise would need more invasive approaches, however its outcome depends on the amount of stresses transferred to the surrounding structures. In an attempt to improve mechanical properties of various dental structures, stress and strain analyses under various loading circumstances has become an integral part of researches. This study was aimed to assess the effect of three different framework materials on stress distribution over implants and bone tissue-simulating materials using finite element analyses method. Materials and methods: Three-dimensional finite element model was created on commercial engineering CAD/CAM package. Bone and mucosa were modeled with simplification, while implant system manufacturer data gave sufficient geometrical data to model it exactly. The modeled parts were transferred to ANSYS for assembly, meshing, and analysis. Three types of framework materials were chosen (Cr Co, Titanium, and PEEK) to be studied under vertical and lateral loads. Results: Bone sensitivity to framework material was demonstrated as, increasing framework material elasticity reduces bone stresses. While the total deformation of bone in case of Cr Co and Titanium frameworks were equivalent, PEEK material showed the highest bone deformation. All implant complex components also showed increasing stresses and deformation with reducing framework material elasticity. Under the proposed loads, no failure occurred in any component of the model, because Von Mises stress values were found lower than physiological limits.