Dr. Rita Kandel is Chief of Pathology and Laboratory Medicine at Mount Sinai Hospital in Toronto, and along with a staff of over 200 medical professionals, Kandel and her team are attempting to use 3D printing technology to build new tissues to replace human joints damaged by injury or disease.

Dr. Kandel says those replacement parts will be built in her lab. And they'll be built within the next five years.

The Mount Sinai hospital researchers say they've developed their technique – which uses a patient's own tissues – to replace human bones and that those bones are created by a 3D printer.

According to Kandel, a joint is comprised of two parts – bone and cartilage. The current technique for joint replacement is based on metal or plastic prosthetics which take the place of damaged bone. Those parts eventually wear out over time and are a source of pain and ongoing discomfort for patients. Kandel's method prints a bone replacement from a calcium phosphate compound, a compound which apes the properties of the human skeleton itself.

3D tissue printerThe printed "bone" is used as a sort of  scaffolding to replace cartilage, and that cartilage is regenerated from a patient's own stem cells. The 3D printed part is porous and biodegradable, and Kandel says it will actually dissolve over time as natural bone grows around it.

"You completely reconstruct a normal joint using the patient's own cells," Kandel said. "There's no metals or plastics – and no typical way of failure – that's found in these prostheses."

The team has already created replacement knee joints and used them in animals, and they say the procedure will be migrated for use in humans within the next few years.

Used in conjunction with research by graduate students at the University of Toronto who are developing a 3D printer which produces tissue closely resembling human skin, Kandel says stem cells, or for that matter, nearly any other genetic matter, can be combined with calcium chloride to produce a soft tissue.

This tissue can be adjusted for thicknesses and texture, and it's the final piece of the puzzle.