Evaluation of bone plate with low-stiffness material in terms of stress distribution.

The aim of this study is to evaluate a newly developed bone plate with low-stiffness material in terms of stress distribution. In this numerical study, 3D finite element models of the bone plate with low-stiffness material and traditional bone plates made of stainless steel and Ti alloy have been developed by using the ANSYS software. Stress analyses have been carried out for all three models under the same loading and boundary conditions. Compressive stresses occurring in the intact portion of the bone (tibia) and at the fractured interface at different stages of bone healing have been investigated for all three types of bone-plate systems. The results obtained have been compared and presented in graphs. It has been seen that the bone plate with low-stiffness material offers less stress-shielding to the bone, providing a higher compressive stress at the fractured interface to induce accelerated healing in comparison with Ti alloy and stainless-steel bone plate. In addition, the effects of low-stiffness materials with different Young's modulus on stress distribution at the fractured interface have been investigated in the newly developed bone-plate system. The results showed that when a certain value of Young's modulus of low-stiffness material is exceeded, increase in stiffness of the bone plate does not occur to a large extent and stress distributions and micro-motions at the fractured interface do not change considerably.

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