Researchers invent new type of artificial bone that can be shaped with a 3-D printer

Researchers have invented a new type of artificial bone capable of being shaped using a 3-D printer for customised implants.

The new material, which they call hyper-elastic bone, appears to act like natural bone in the body and can repair deformed bones and some injuries, the team reported in the journal Science Translational Medicine.

According to the team at Northwetern University, when tested in a monkey, the bone fused to the animal's skull, allowing new blood vessels to grow into it.

"Within four weeks, the implant had fully integrated, fully vascularised with the monkey's own skull. And there is actually evidence of new bone formation,"

Adam Jakus, a postdoctoral fellow in the department of materials science and engineering at Northwestern, told reporters in a telephone briefing.

The team hoped to gain permission to test the implants in people in the next five years. The material which is cheap, would likely be useful for a range of bone injuries, including for the spine, skull and jaw, they said.

Currently, the best option was a bone graft from the patient, which could be painful and which did not always work well, or bone donation from a deceased person. These transplants often did not heal well and artificial bone grafts currently being developed were often brittle and also carried the risk of being rejected.

The hyperelastic bone, described in a study published yesterday in Science Translational Medicine, was mostly made from a naturally occurring mineral called hydroxyapatite.

Hydroxyapatite, a form of calcium found in bone had already been used in reconstructive surgeries, was extremely brittle, but the researchers mixed it with a polymer to add flexibility. They then 3D printed bone graft from this new, promising material and tested it in various experiments.

"The first time that we actually 3D printed this material, we were very surprised to find that when we squeezed or deformed it, it bounced right back to its original shape," Ramille Shah, one of the study's authors and an assistant professor of materials science at Northwestern University, said during a press call.