3D Printing Optimization of a Novel Bone Biomaterial for Preformed Implants

Tetranite is a calcium-based bone adhesive, developed by RevBio, intended to fixate bone fractures and regenerate new bone over time. Tetranite powder combined with a liquid activator lends itself well to powder-bed inkjet (binder jet) 3D printing, which could be used to construct scaffolds and grafts. 3D printing allows for variations in design, geometry, density, and other configurable parameters. Tetranite provides a significantly shorter time in the operating room for the patients and promotes bone regeneration, while other methods are more invasive, require more complex surgery, and may be rejected by the host causing more difficulties. The intended printer design goals were a Ø20 x 10 cm build volume, 0.25 mm dimensional accuracy, and configurable implant strength from 3 to 25 MPa in compressive loading. Current existing 3D printing technologies do not provide the required precision and customization to manufacture implant scaffolds that meet the desired standards for geometry and mechanical strength. Our team will optimize a binder jet 3D printer to produce the desired high-quality, generic Tetranite scaffolds for applications such as a cranial flap replacement, dental, metaphyseal and spine reconstruction. These printed scaffolds will be implanted and bonded to surrounding bone with the current state injectable solution. The printer will be capable of producing scaffolds within a 20x20x20cm volume with 0.25mm layer resolution. Scaffolds will be capable of withstanding compressive loads between 25 MPa for dense structures and 3-15 MPa for porous structures. The key deliverables for this project includes a prototype of the binder jet 3D printer, accompanying software, comprehensive documentation, and a biomechanical data package.