Evaluation of Stress Distribution around Porous Tantalum Trabecular Metal and Titanium Dental Implants in Different Bone Densities: A Three- Dimensional Finite Element Analysis

Abstract

Purpose: Evaluation of stress distribution in different bone densities around Porous Tantalum Trabecular Metal (PTTM) and Titanium (Ti) implants using finite element analysis. Materials and Methods: Three-dimensional models using 4.7 mm×11.5 mm PTTM and Ti implants were simulated with a mandibular bone in the canine site. Four different bone qualities (D1, D2, D3, and D4), and three different static occlusal forces (70N vertical, 35N oblique (60°), and 14N horizontal) were used. Qualitative and quantitative analyses of maximum von mises stress were performed using ABAQUS software and 24 different models were obtained. Results: Under vertical loading, stress values in all cortical bone densities around the PTTM implant were higher than Ti implant and had a uniform distribution pattern in the bone around both types of implants. Under oblique and horizontal loadings, the stress levels in D1- D3 cortical bone densities around the PTTM implant were lower than that ofTi implant, and the stress concentration was adjacent to the neck of both implants. Stress values in the all trabecular bone densities under vertical loading and in D1 and D4 densities under horizontal loading, around the PTTM implant were lesser than that ofTi implant but under oblique loading in D2-D4 densities the opposite results were obtained. Under all loading conditions in the trabecular bone around both types of implants, stress was distributed adjacent to the entire length of the implant at D3 and D4densities, but at D1 and D2densities, the maximum stress value was distributed in the coronal area of the bone. Under vertical and obliqueloadings, the stress level in the PTTM implant body was lesser than the Ti implant body and under the horizontal loading it was higher than that of Ti implant body in all bone densities. In all bone densities and under all loading conditions, the highest stress concentration was in the modular crest of both implants. Conclusion: The stress values and distribution patterns around the two types of implants were almost similar and PTTM implants had no significant advantage over Ti implants.