Jin Zhongmin

The Research of Technique on Fabricating Hydrogel Scaffolds for Cartilage Tissue Engineering Based on Stereo-lithography

Based on stereo-lithography, the polyacrylamide hydrogel scaffolds with controlled accurate internal structures were fabricated. The structure accuracy of the scaffolds was evaluated by the size measurement compared with the CAD model. The mechanical property evaluation showed that the hydrogel compressive modulus of elasticity reached 4.54MPa, which was similar to that of the articular cartilage, therefore meeting the basic requirements of cartilage tissue engineering. The technique based on stereo-lithography showed promising in fabricating cartilage scaffolds.

3D Printing and application of large-size joint os-teochondral scaffolds

Implantation and long-term failure of artificial joints can cause unrecoverable tissue loss, whereas small-scale biodegradable osteochondral scaffolds can restore the mechanical environment and induce tissue regeneration within articular lesions, thus providing a new therapeutic strategy for repairing large-size defects. However, treatment development has been challenging because of the complex physical structure and mechanical environment of the lesions, and the demanding manufacturing techniques and surgical implantation strategies for multi-material composite scaffolds. This paper presents a novel multi-material osteochondral scaffold, and its bio-manufacturing technique and implantation. To induce tissue growth, PEG (polyethylene glycol), β -TCP ( β -tricalcium phosphate), and PLA (polylactide) biomaterials are selected to develop the new scaffolds. Based on limited radiological image data, techniques for reverse engineering, finite element analysis, and 3D printing are used to establish the cartilage lesion model in a sheep knee joint. Based on the mapping relationship between the scaffold physiological characteristics and joint defect mechanical properties, large-size biomimetic osteochondral scaffolds and their fixations are designed to fasten themselves securely to defects. Experiment results show that scaffold implantation restores the defects initial mechanical environment. Therefore, the proposed large-size osteochondral scaffolds through 3D printing technique is expected to provide a new treatment strategy for repairing large osteochondral defects.