Bionic integrated scaffold of tissue engineered cartilage-subchondral bone using 3D printing rapid prototyping technique

摘要

Introduction The boundary structure between cartilage and subchondral bone is named calcified cartilage zone, it has important physicochemical functions. However, the tissue-engineered cartilage and bone by current methods usually lacks this boundary structure. Based on the extensive study of human articular osteochondro tissue morphology, here we proposed a concept of integrated scaffold which contains cartilage layer, subchondral bone, and the boundary structure between them. Materials & Methods We measures the parameters needed to fabricate the scaffold, including the thickness of each layer, the cell density in each layer, and the connection mode between each layer. Then we used computer aided design(CAD) software to build the CAD model of the scaffold based on bionics principle. We converted the CAD model into Standard Template Libarary(STL) format, and imported it into 3D printer. The powder spreading device of the printer printed the scaffold layer by layer with the given parameters, finally the 3D scaffold was produced. Results The scaffold produced in our study was similar in morphology with the host tissue, particularly, the boundary structure between cartilage and bone could provide suitable microenvironments for the seed cells to differentiate into either osteoblasts or chondrocytes. The application of 3D printing rapid prototyping technique made the engineered scaffold match the bone defect in anatomical shape, which ensures the accuracy oflocal implantation; moreover, the inner structure of the scaffold resembles that in host tissues, which ensures cell vaccination and nutrient supply. Conclusions 3D printing rapid prototyping technique can be used to fabricat the tissue-engineered bionic scaffold of cartilage and bone, it has many advantages such as simplicity of operation, high accuracy and good repeatability to realize industriliation.