Whether 3D printed or not, bone replacements have always posed several problems for patients. For one, if the patient is a child, they will quickly grow out of whatever artificial implant they may receive. And even if the patient is an adult, they still need a bone replacement that will adapt to changes in their bodies as they age, just like a real piece of the human body. Luckily for everyone, researchers at several organizations are investigating new ways to create the perfect bone replacements—using 3D printing.
Versatile Bone Transplants
Chinese company Xi’an Particle Cloud Advanced Materials Technology Co., Ltd. announced in March that it been able to transplant a biodegradable 3D-printed bone into a rabbit. Using a unique process called Filament Free Printing, the company overcame many of the common issues of FDM 3D printing, such as expense and wastefulness.
The new precise method uses polymers, ceramics and UV light to create a more volatile ink. This ink can create artificial bones with the same pore structures, strength and versatility of real bones. The rabbit in question, who received a 3D-printed femoral condyle bone, started to grow new cells of its own on the artificial implant. The company plans to begin human trials of the new bone with their PCPrinter BCTM 3D printer this June.
The potential benefits of such as versatile bone implant are numerous: it could help patients who have suffered bone loss from cancer or other degenerative diseases. The technology is also much less costly, as current methods take bone grafts from the patient’s body or from cadavers.
Stem Cells for Precise Replacements
Another promising method of 3D printed bone replacements takes a completely different approach. Researchers hope an ultra-personalized bone replacement could be possible by printing 3D tissue using stem cells from the patient in question. Doctors could take a picture of the bone that needs replacement, input the data into the computer, and print a replacement that fits the defective bone precisely.
Kevin Shakeshaff, a University of Nottingham pharmacist, said, “The tissues of our body are structured at the level of single cells. Using 3D printing, we can position cells in precise places.”
The 3D bioprinter would create a scaffold for the bone, then cover it with adult human stem cells. The cells can then become many different types of bodily tissues. After the bone is implanted into the body, the scaffold will slowly degrade and be replaced by authentic bone within three months.
"The first advantage is you get something in the exact shape of the defect you're trying to replace," Shakeshaff said. "More subtly, you have the ability to organize where the cells go within the scaffold," he said.
Using a polylactic acid polymer and alginate gel substance, doctors are able to create a strong bone with cushioning for the cells. Patients will also benefit from better blood vessel formation than other methods.
The most exciting part about bone replacement research is that there are a wide variety of disparate methods being developed in tandem. This versatility of options will not only benefit patients with unique needs, but will help researchers further develop the best possible methods using 3D printing.