3D Printed Cellular Structures of PLA for Engineering Artificial Bone

Abstract

AbstractSince the development of additive manufacturing technologies, periodic structures with controlled morphologies have emerged as a new tool for the designing cellular materials. Morphological variabilities are also often noticed in nature, especially in bone structures, and can be inspirational for the design of artificial tissues. It is known that the mechanical properties of cellular biomaterials mimicking bone are dependent on the morphological properties of the structure, including the shape and size of the repeating unit cell from which they are manufactured. Fused Deposition Modeling (FDM) is a powerful method to create porous structures for tissue engineering, thanks to the possibility to print objects of complex geometry and different configurations. The present work deals with the creation of open porosity structures according to different morphologies, we studied the relationship between the wall thickness of polylactic acid (PLA) structures and the mechanical properties, namely the elastic modulus, the yield stress, the plateau stress, and the densification strain. The cellular PLA structures were made with interconnected hollow spherical cells with 10 mm of diameter according to a hexagonal stack and a wall thickness of 0.2 mm, 0.4 mm, 0.6 mm and 0.8 mm. The mechanical properties were evaluated by mechanical compression tests. The experimental results indicated that the PLA structures with controlled morphologies show specific and interesting mechanical properties.KeywordsTissue engineering3D printingCellular structurePLA