Mechanical characterization of low-cost 3D FDM printed scaffolds fabricated with synthesized PLA/HA bio-composite filament

Abstract

Bone tissue engineering has gained popularity as a potential alternative in bone defect treatment, where the synthetic graft can be generated by a 3D biomaterial framework (scaffold) that yields shape and initial mechanical strength to facilitate cell bone formation. Biopolymer-based, Poly Lactic Acid (PLA)/Hydroxyapatite (HA) scaffolds were found to have a similar structure, composition, and mechanical properties as natural bone. The objective of this work was to fabricate 3D scaffolds with PLA and HA using a low-cost fabrication process such as Fused Deposition Modeling (FDM), which can be used to construct scaffolds tailored to an individual's specific need in a controlled and customizable process. The study primarily focuses on the synthesis, and mechanical and morphological characterization of PLA/HA filament and its scaffolds. The fabricated 3D printed PLA/HA scaffolds had an interconnected and highly porous structure, resembling natural bone porosity. The addition of HA had a significant effect on the PLA/HA composites although there are no notable differences in mechanical properties between 10–15 % PLA/HA composites. The microstructural morphology of the PLA and PLA/HA composite filaments observed under Scanning Electron Microscopy (SEM) showed a relatively well mixed and homogenous mixture and Energy-dispersive X-ray Spectroscopy (EDS) testing of the filaments’ surface topography further showed a mostly homogeneous presence of HA throughout. The 3D printed scaffolds showed a larger pore size due to the inclusion of HA. Additionally, with the increased percentage of HA, the pores became more uneven and irregular. The preliminary results of this study show a promising potential for personalized scaffold design for bone tissue regeneration.