Researchers create bone-like material using 3D printer

Over the past decade, 3D printing technology has made the transition from huge expensive units used by industry to produce prototype components to small desktop units like the DIY MakerBot Thing-O-Matic that are within the reach of home users. But home users looking to produce custom household objects aren't the only ones set to benefit from advances in 3D printing technology, with 3D bio-printers offering the prospect of creating organs on demand for replacement surgery. Now researchers have used a 3D printer to create a bone-like material that could be used to create customized scaffolds to stimulate the growth of replacement bone tissue.

For their work, researchers at Washington State University (WSU) optimized a commercially available ProMetal 3D printer designed to make metal objects. The re-purposed printer uses an inkjet to spray a plastic binder over a bed of powder in layers just 20 microns thick - that's about half the width of a human hair. When paired with actual bone and used with some bone growth factors, the resulting bone-like material acts as a scaffold for new bone to grow on before dissolving with no apparent ill effects. The researchers say this would allow customized scaffolds to be produced for new bone to grow on in orthopedic procedures, dental work and to deliver medicine for treating osteoporosis.

"If a doctor has a CT scan of a defect, we can convert it to a CAD file and make the scaffold according to the defect," said Susmita Bose, a professor in WSU's School of Mechanical and Materials Engineering and co-author of the WSU study.



The researchers say they have already seen promising results in vivo tests on rats and rabbits and after just a week in a medium with immature human bone cells, the scaffold was supporting a network of new bone cells. The main finding of their research was that the addition of silicon and zinc more than doubled the strength of the main material, calcium phosphate.
Research into the use of three-dimensional scaffolds to stimulate the growth of bone and/or tissue within the body isn't new, with researchers at MIT using a similar method to stimulate bone and cartilage growth when transplanted into knees and other joints. Meanwhile, Columbia University researchers have been looking at growing dental implants in a patient's empty tooth socket using a tooth-shaped scaffold. But the use of 3D printing technology would make it easy to create scaffolds specifically tailored for individual patients.
The WSU team's study has been published in the journal Dental Materials.