A combination of engineering, materials science and medical innovation in Chicago has led to the development of hyperelastic ‘bone’ biomaterial, bringing 3D printed bone implants one step closer to reality.

The Northwestern University research team was led by Ramille N. Shah, considered a pioneer in the new and developing 3D printable biomaterials field. She is assistant professor of materials science and engineering in Northwestern’s McCormick School of Engineering and of surgery in the Northwestern University Feinberg School of Medicine. She is also a resident faculty member in the Simpson Querrey Institute for BioNanotechnology. The Shah TEAM (Tissue Engineering and Additive Manufacturing) lab is located in the heart of the NU Medical Campus in downtown Chicago, and interacts closely with medical clinicians and surgeons.

The groundbreaking development could eliminate the need for painful, invasive bone harvesting from elsewhere in the body to replace missing or damaged bone, and avoids the issue of metallic implants which will not grow along with the patient.

“Adults have more options when it comes to implants,” said Shah. “Pediatric patients do not. If you give them a permanent implant, you have to do more surgeries in the future as they grow. They might face years of difficulty.”

The Northwestern team developed a 3D printable ‘ink’ that produces a synthetic bone implant that rapidly induces bone regeneration and growth. Composed mainly of hydroxyapatite, a calcium mineral found naturally in human bone, the ink also contains a biocompatible, biodegradable polymer that’s already utilised in medical applications such as sutures. Using a 3D printer, the ink can build up individually customised, three-dimensional bone-replacement implants. The polymer ensures the biomaterial retains a hyperelastic consistency, allowing the implants to stretch with the surrounding bone as it grows. The hydroxyapatite induces bone regeneration, which should result in the implants gradually being replaced by natural bone over time.

Shah added: “We can incorporate antibiotics to reduce the possibility of infection after surgery. We also can combine the ink with different types of growth factors, if needed, to further enhance regeneration. It’s really a multi-functional material.”

Initial animal tests in animals look promising: after just four weeks, an implant placed in a monkey’s skull had fully healed, fusing with the existing bone, and those placed in mice were rapidly integrated by the rest of the body, allowing blood vessels and cells to grow on and through them.

The material’s composition makes the synthetic bone easily customisable and quick and inexpensive to produce. Ultimately, Shah hopes that hospitals may one day have 3D printers, where customised implants can be printed while the patient waits: “The turnaround time for an implant that’s specialized for a customer could be within 24 hours. That could change the world of craniofacial and orthopaedic surgery, and, I hope, will improve patient outcomes.”

Featured image: A hyperelastic bone in the shape of a section of the human spine, 3D printed using the ink developed at Northwestern University. Credit: Adam E. Jakus

(Via Northwestern University and NewAtlas)