"Smart" Medical Implants Dissolve After Body Heals

A team at the National Science Foundation Engineering Research Center (ERC) for Revolutionizing Metallic Biomaterials at North Carolina Agricultural and Technical State University is working to transform current medical and surgical treatments by creating 'smart' implants. The major goal is to transform metallic biomaterials to improve treatments for orthopedic, craniofacial, neural, and cardiovascular ailments. The ERC's technology will be used in biocompatible and biodegradable implants for reconstruction and regeneration. These implants could include such devices as screws, wires, and plates with the capability for controlled degradation and emission from the body when they've served their purpose. A device now in testing is a cage to immobilize vertebrae after spinal fusion operations.

Transcript

00:00:00 ♪ MUSIC ♪ [AMBULANCE SIRENS] MILES O'BRIEN: We all know, accidents happen, and doctors often have to use screws or even metal plates to support broken bones while they heal. Afterwards, they're sometimes surgically removed or they just stay there, increasing the chance of complications down the road. What if that metal could just disintegrate on its own? JAG SANKAR: If you make it very thin, you can do biodegradable sutures and staples.

00:00:36 MILES O'BRIEN: With support from the National Science Foundation, materials engineer Jag Sankar and a team at North Carolina Agricultural and Technical State University are working to make that happen. Here at a center called "Revolutionizing Metallic Biomaterials" they're developing new metals for use in plates, staples, heart stents and surgical screws, all designed to eventually just dissolve away safely. JAG SANKAR: Which means the future implant, whether it's orthopedic or cardiovascular, after the person cures, slowly

00:01:11 it will biodegrade, and it won't be in your body. MILES O'BRIEN: Sankar says creating new bio-materials from scratch is much easier said than done. JAG SANKAR: You need to have facilities and people working on different things. MILES O'BRIEN: Materials engineer Christopher Smith says a main ingredient in their bio-materials recipe is magnesium. Our bodies use it to build bone and muscle. And so that makes it an ideal building block for new biodegradable metal alloy implants.

00:01:42 CHRISTOPHER SMITH: We take a pure magnesium block. We cast it until it becomes liquid molten magnesium. Then, we add our additional metals to create our alloys. These elements make our alloy more robust for medical devices. LAB WORKER: Looks good. [laughs] MILES O'BRIEN: Sankar says they're testing a range of different magnesium-based alloys. One type does not fit all. JAG SANKAR: So that means we need to create a material database, slew of materials having different magnesium alloy

00:02:16 properties. What suits for me at my age is different from somebody else of some other age or a woman. SERGEY YARMOLENKO: ..we are developing the recipe. MILES O'BRIEN: Sergey Yarmolenko is formulating biocoatings that are applied to the magnesium-alloys to keep them from dissolving too soon. SERGEY YARMOLENKO: It allows us to develop very tiny and very accurately layers of materials we should want. MILES O'BRIEN: Chemist Boyce Collins uses CT scans to monitor implants as they disintegrate.

00:02:49 BOYCE COLLINS: We can take an image at two weeks, four weeks, 12 weeks. This is a magnesium anchor that's been absorbed into a rabbit femur. A femur being the thigh bone. MILES O'BRIEN: It will take years of testing to make sure these materials are safe and effective. Sankar expects in the next ten years that metal plates and screws for broken bones, you know, the ones that set off metal detectors at airports, won't have to be a permanent fixture at all. They'll just disappear on their own. For Science Nation, I'm Miles O'Brien.