While industrial and consumer use of 3-D printing has now become fairly common, a potentially revolutionising use of the technology is just coming to light—bio-printing, or using inkjet technology to print layers of living cells on gel media or sugar matrices to gradually develop body parts. In 2013, the University of Hasselt, Belgium, successfully printed a new jawbone for a 83-year-old patient. The segment, in the last couple of years, has gone from elementary printing of plastic vascular bundles and bones to melding of biological and electronic to create a human outer-ear prototype. An ear-like scaffold made from hydrogel with living cells that will grow to form cartilage and silver nano-particles that will function as the antenna has been developed by researchers at Princeton University and John Hopkins University, US.
There is still some ground to cover before an organ of incredible complexity of structure and function, like a kidney or a liver, can be printed—at present, printing sheets of tissue that can be used to repair such organs are being printed. This improves the odds for patients—many often die waiting to receive a transplant, thanks to the acute shortage of viable donor organs. Most of the bio-printing business—totaling $537 million in 2014—has focussed on titanium hips and polymer bones. But living organ prints portend a much bigger boom for market. Bio-printing could eventually find cosmetic use (think of living, growing skin covering electronically-guided prosthetic limbs).