Synthetic bones promote natural bone regeneration after being implanted into animals.

Credit: Adam E. Jakus
Credit: Adam E. Jakus

Ramille Shah at Northwestern University in Evanston, Illinois, and her colleagues used a 3D printer to generate 'hyperelastic bone'. The main component of the material was hydroxyapatite — a calcium mineral similar to one found in bone — which was mixed with one of two polymers used in medicine and tissue engineering. Grafts built with the material (main picture) and implanted into mice, rats and one macaque became integrated into tissue and stimulated bone growth without adverse effects. Moreover, a 3D-printed 'bone' shaped like a section of human femur was able to withstand loads similar to those experienced naturally.

The material can be rapidly printed into a variety of shapes (human spinal section, inset) and is easy to use in surgery, the authors say.

Sci. Transl. Med. 8, 358ra127 (2016)