3D Printing of Novel Gradient Osteochondral Scaffolds to Bridge the Gap Between Cartilage and Bone

Osteochondral tissue has a graded structure spanning from the subchondral bone region beneath the joint surface to the hyaline cartilage region at the joint surface. Biological, physiological, and mechanical properties over the regions cross-section vary greatly; this provides a significant challenge for tissue-engineered structures addressing osteochondral defects. The objective of this research is to investigate the effects of scaffold pore structure on mechanical, biological, and physiological properties of 3D printed tissue engineered osteochondral scaffolds. Our results indicate that gradient pore structures improve both mechanical properties and cell performance when compared to homogeneously distributed pores and non-porous structures. This study also indicates that including nanocrystalline hydroxyapatite (nHA) into the hydrogel scaffold further improves cellular performance compared to both porous scaffolds without nHA and nonporous scaffolds.