One technique involves a portable bioprinter that could be carried to wounded soldiers on the battlefield where it would scan the injury, take cells from the patient and print a section of compatible skin.
Another uses a three-dimensional printer combining donor cells, biofriendly gel and other materials to build cartilage.
The 3-D printer was shown at work, building a prototype of an ear during a half-hour demonstration at a Washington science conference.
Hod Lipson of Cornell University in New York said it worked much like an ink-jet printer.
"It spits out plastic to gradually build an object layer by layer... after a couple of hours you end up with a real physical object that you can hold in your hand," he said.
"Just imagine -- if you could take cells from a donor, culture them, put them into an ink and recreate an implant that is alive and made of the original cells from the donor -- how useful that would be in terms of avoiding rejection," said Lipson.
