New material is promising, but has yet to be tested in humans
A new synthetic material called hyperelastic bone, or HB, could be “the next breakthrough” in reconstructive surgery, new research shows. The HB can be implanted under the skin as a scaffold for new bone to grow on, or used to replace lost bone matter altogether. Though it hasn’t been tested in humans yet, early experiments on animals appear to have been successful, with “quite astounding” results, according to the researchers.
The hyperelastic bone, described in a study published today in Science Translational Medicine, is mostly made from a naturally occurring mineral called hydroxyapatite. Hydroxyapatite — a form of calcium found in bone and already used in reconstructive surgeries — is extremely brittle, but the researchers mixed it with a polymer to add flexibility. They then 3D print 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.
The hyperelastic bone can be easily cut, rolled, folded, and pressed into areas missing bone material without glue or stitches, Shah said. It is also highly porous and absorbent — which is crucial for bone graft material to encourage the growth of blood vessels into the surgery area. (Without veins and capillaries carrying blood to the target site, the surrounding tissue dies.)
The scientists tested the hyperelastic bone in a range of experiments. They placed human stem cells into a number of scaffolds 3D-printed from hyperelastic bone (the same type of structure that might be used as an implant in surgery). The cells not only grew without any difficulty on the scaffolds, filling up the available space in a matter of weeks, but also ended up producing their own bone minerals.