But without scaffolding or patterns to follow, holding something soft together can be challenging: blood vessels, for example.
So researchers are experimenting with support gels that hold fragile structures up while they're printed. They just figured out which chemicals to use to support silicone printing, which could lead to a range of useful soft parts, like fluid pumps or tracheal implants.
And live replacement tissue might not be far behind, after all. Carnegie Mellon University is already using a similar technique to print heart arteries.