“This is a very unique material that’s sort of a synthetic analog to natural bone,” Ramille Shah, professor of materials science and engineering at Northwestern University in Evanston, Illinois, told Digital Trends. “The unique thing about it is that it is 90 percent hydroxyapatite, which is the main mineral component of bone. However, instead of being very brittle like ceramic, it’s actually very elastic.”
Given this unique property, it’s interesting to hear that the hyperelastic abilities of the 3D-printed “bone” — which lets it regain its original shape when squashed or deformed — was actually a happy accident in the lab.
“I wish I could say that was something we knew was going to happen, but it took us by surprise,” Shah continued. “We didn’t expect that this material would have the type of properties it wound up having. We were incredibly surprised when we 3D-printed the first samples. We expected it to be a bit less brittle than some [previous experiments], but we didn’t think it would be close to this elastic.”
In a study, Shah and her fellow researchers put human stem cells extracted from bone marrow on a sample of the 3D-printed material, and were able to show that this caused them to mature into bone cells. The bone-like material was also used to help mend spinal defects in rats, as well being utilized to heal the damaged skull of a rhesus macaque monkey.
In addition, the team was able to prove the material was safe by placing it under the skin of mice, which suffered no ill effects. They hope that human trials will follow in the next half-decade.
“This work would fit in well anywhere that bone regeneration is needed — from spine to craniofacial, or any other fractures,” Shah concluded. “Any bones that are broken in the body could theoretically have this material applied.”
