|Bone cells attach to 3-D-printed scaffolding. When bone completely heals the material will degrade.--Courtesy of U. of Pittsburgh|
The National Science Foundation has coughed up almost $31 million to help solve a problem that plagues the medical device industry: metal surgical implants that eventually deteriorate or otherwise malfunction. The agency has been investing this research money since 2008 in an effort to develop what it has dubbed "smart implants" that address the underlying medical issue but then dissolve.
One academic supported by this NSF project funding, which is funneled through its Engineering Research Center for Revolutionizing Metallic Biomaterials, is University of Pittsburgh bioengineering professor Prashant Kumta.
He has developed biodegradable implants made of iron and magnesium that are custom-built using a customized 3-D printer that mixes glue droplets with mineral powder. The idea is to create devices that are made of these minerals to serve as a scaffold to which bone cells will attach. Bioresorbable stents used in the vasculature are already rapidly moving into the market.
So, instead of bone implants such as metal screws, pins, rods or plates that remain in the body and offer the potential for degradation and malfunction long-term, patients would instead have implants made of these biologically necessary minerals that would serve as the basis for healing and then safely biodegrade.
Magnesium "has the mechanical characteristics that meet natural bone, both from the strength [and] the toughness as well as the density. It has the perfect density that will match with natural bone," Kumta told Voice of America, a media outlet that is backed by the U.S. government. He's also working on a novel calcium phosphate putty to be injected in the spaces around its 3-D printed biodegradable implants, as well as between fractured bones.
"You can actually create an architecture that mimics the original bone that the patient has lost," he said. "The fixation plate will provide the mechanical strength needed to carry the load, and the bone-wide filler would help provide the healing and the bone formation."
"Rather than implanting a screw or plate or joint, doctors could give the body's own regenerative ability a more effective method to heal itself," concluded Kumta.
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