Numerical analysis of porosity effects on mechanical properties for tissue engineering scaffold

Abstract

Tissue engineering has emerged as a promising solution for healing fractured human bones through the utilization of porous scaffolds that offer synthetic support to the damaged bone. This current study aims to identify an optimal porous scaffold design that exhibits superior mechanical properties. Utilizing Fusion 360 software, a unit cell was modelled with circular, elliptical, and flower shapes, each oriented differently. A circular porous scaffold, comprised of eight-unit cells, was fabricated using a 3D printer. Compression tests were conducted on this printed scaffold using a Universal Testing Machine (UTM). A comparative analysis was performed between the experimental and numerical deflection, revealing an approximate 8.8% variation in comparison to the experimental deflection. Static structural analysis of the modelled scaffolds was carried out employing ANSYS software. Scaffolds constructed with PLA (Polylactic Acid) and PGA (Polyglycolic Acid) materials exhibited similar von-Mises stress results during their structural assessments. The circular geometry scaffold displayed a Von-Mises stress of 330 MPa, while the elliptical geometry scaffold exhibited 76 MPa. The findings led to the conclusion that the elliptical model possessed a lower von-Mises stress compared to the circular model, although the porosity of the elliptical model remained around 50%. Furthermore, it was observed that the Maximum Equivalent stress of the elliptical scaffold with a vertical orientation was 63% higher than that of the same scaffold with a horizontal orientation. For square geometry scaffolds, maintaining a constant porosity percentage of 83.6%, the model with 512-unit cells predicted the minimum von-Mises stress when compared to scaffolds with 1, 8, and 64 - unit cells.