Experimental and computational characterization of designed and fabricated 50:50 PLGA porous scaffolds for human trabecular bone applications

The present study utilizes image-based computational methods and indirect solid freeform fabrication (SFF) technique to design and fabricate porous scaffolds, and then computationally estimates their elastic modulus and yield stress with experimental validation. 50:50 Poly (lactide-co-glycolide acid) (50:50 PLGA) porous scaffolds were designed using an image-based design technique, fabricated using indirect SFF technique, and characterized using micro-computed tomography (micro-CT) and mechanical testing. Micro-CT data was further used to non-destructively predict the scaffold elastic moduli and yield stress using a voxel-based finite element (FE) method, a technique that could find application in eventual scaffold quality control. Micro-CT data analysis confirmed that the fabricated scaffolds had controlled pore sizes, orthogonally interconnected pores and porosities which were identical to those of the designed files. Mechanical tests revealed that the compressive modulus and yield stresses were in the range of human trabecular bone. The results of FE analysis showed potential stress concentrations inside of the fabricated scaffold due to fabrication defects. Furthermore, the predicted moduli and yield stresses of the FE analysis showed strong correlations with those of the experiments. In the present study, we successfully fabricated scaffolds with designed architectures as well as predicted their mechanical properties in a nondestructive manner.