Biomedical Materials
Current Projects: Past Projects:- Designing Neural Probes for Long Term Neural Recording in Large Brains
- Stereolithographic Synthesis of Hydroxyapatite Bone Scaffolds
Investigation of Load-Bearing Scaffolds for Critical-Size Bone Defects
Personnel: Weiting Deng (Ph.D. student in Medical Engineering)
Bone tissue possesses an innate regenerative capability to sufficiently heal small sites of damage, for instance some types of fractures. The reconstruction of large bone defects (typically >2cm, depending on the anatomical site) caused by trauma, disease or tumor resection is a fundamental challenge for orthopedic and plastic surgeons. This type of bone lesion requires clinical intervention if functional restoration and complete healing is to be achieved. Additive manufacturing (AM), also named 3D printing, is an emerging technology that permits the fabrication of complex-shaped structure with high precision using layer-by-layer printing. This freedom of design has allowed engineers to have an unprecedented control over a scaffold's structure and composition. Additive manufacturing offers the capability to fabricate customized bone scaffold without size limitation and meet the urgent requirement when implants are needed immediately. Significant progress has been made in developing biocompatible materials with AM, but challenges still remain in load-bearing scaffolds of matching the bone stiffness - due to the large heterogeneity in bone structure and difference across patients, and maintaining structural integrity.
To tackle this problem, rational designs are required through both material approach and structure approach. Vat photopolymerization was chosen as the fabrication method due to its ability to achieve high resolution. Techniques such as SLA and DLP can achieve micron level resolutions while two photon lithography can achieve sub-micron resolutions. Our central hypothesis is that stiffness matching between natural bone and scaffold could be achieved via modification of biocompatible photo-crosslinkable resins and scaffold design of spinodal structure.
