Paper Title
APPLICATION OF 3-D PRINTING BONE SCAFFOLDS GRAFTED WITH BMP-2 ON BONE TISSUE REGENERATION

Abstract
Abstract - The main purpose of this study is based on a three-dimensional printing (3DP) technique to develop biodegradable, osteoconductive, biocompatible porous scaffolds for defective bone tissue regeneration. The developed 3D-printed scaffolds were then grafted with human bone morphogenetic protein-2 (BMP-2) via the actions of polydopamine (PDA) coatings. Before in vivo biological evaluations of animal implantations, the physiochemical properties of 3DP PLA scaffolds, long-term release profile of BMP-2, cellular behaviors and osteogenic activities of cocultured with human mesenchymal stem cells (hMSCs) were assessed. The findings of this work showed that BMP-2/PDA/PLA scaffolds with interconnected microporous architectures exhibited lower lactic acid dissolution as compared to the freeze-PLA scaffold, and revealed sustained release of BMP-2 for up to 35 days. The results of osteogenic assay showed that the ALP activity and osteocalcin of hMSCs cultured on BMP-2/PDA/PLA were significantly higher when compared with PLA and PDA/PLA scaffolds. In animal implantation test, these results revealed that 3D-PLA–BMP-2 scaffolds promoted the production of a larger amount of new bone tissues to cause the rate of bone repair, bone mass, and trabecular thickness significantly greater than the other groups.The findings indicate that 3D-PLA–BMP-2 scaffolds as a promising bone substitute for the regeneration of larger bone defects. Keywords - Bone Regeneration, Stem Cell, Poly-Lactic Acid (PLA), Three-Dimensional Printing, Bone Morphogenetic Protein-2.