| Abstract |
Although the architectural design parameters of 3D-printed polymer-based scaffolds-porosity, height-to-diameter (H/D) ratio and pore size-are significant determinants of their mechanical integrity, their impact has not been explicitly discussed when reporting bulk mechanical properties. Controlled architectures were designed by systematically varying porosity (30-75%, H/D ratio (0.5-2.0) and pore size (0.25-1.0 mm) and fabricated using fused filament fabrication technique. The influence of the three parameters on compressive mechanical properties-apparent elastic modulus E-app, bulk yield stress sigma(y) and yield strain epsilon(y)-were investigated through a multiple linear regression analysis. H/D ratio and porosity exhibited strong influence on the mechanical behavior, resulting in variations in mean E-app of 60% and 95%, respectively. sigma(y) was comparatively less sensitive to H/D ratio over the range investigated in this study, with 15% variation in mean values. In contrast, porosity resulted in almost 100% variation in mean sigma(y) values. Pore size was not a significant factor for mechanical behavior, although it is a critical factor in the biological behavior of the scaffolds. Quantifying the influence of porosity, H/D ratio and pore size on bench-top tested bulk mechanical properties can help optimize the development of bone scaffolds from a biomechanical perspective. |
