Mechanical Property Analysis of Triply Periodic Minimal Surface Inspired Porous Scaffold for Bone Applications: A Compromise between Desired Mechanical Strength and Additive Manufacturability

Abstract

Porous structure offers the advantage of minimizing stress shielding phenomena and supports bone ingrowth, thereby improving the long-term durability of scaffolds. Unlike conventional techniques, additive manufacturing is capable of fabricating complex pore architecture in an exceedingly controlled fashion. In this paper, implicit surface modeling technique is used to develop the triply periodic minimal surfaces-based scaffolds of varying architectures. Sheet and solid-based wrapped package graph (IWP) and diamond are investigated by finite element analysis of lattices under compression. Parameters of mathematical trigonometric functions are varied to tune the structural characteristics like pore size, porosity on the elastic moduli, and strength of the scaffold. Results indicate that morphological features could be effectively controlled to achieve the desired bone mimicking architectures. In terms of biomechanical performances, IWP and diamond structures achieved the responses similar to surrounding bone tissue and have the good agreement with the data available in the literature for the range of elastic modulus of bone for various anatomical locations; the numerical results show that the architecture, pore size, and porosity have a major impact on performances of scaffolds. Also, in the biomechanical and clinical context, this work highlights the limitations and capabilities of additively manufactured porous scaffolds, thus proposing a permissible design space for the scaffold fabricated by additive manufacturing. © 2022, ASM International.