"You bite into it and it's a custom fit."
The mouthpieces are coated in medical-grade plastic and resemble large mouthguards with a small, duckbill-shaped spout that pokes out between the lips.
Forty of the mouthpieces can be printed in about 14 hours using the CSIRO's 3D titanium printer, which deposits layer-upon-layer of melted titanium powder to gradually form objects.
3D printing technology has been much-hyped, but it makes the most sense when it's used to create small, customisable objects, Barnes says.
"Lots of people are printing lots of things, but this one actually makes a business case."
The printer has been used to create, among other things, super-light customised shoes for racehorses and small connectors for bicycles.
About one in 25 people have symptoms of sleep apnoea, which causes chronic tiredness and increases the risk of heart disease and early death, according to advocacy group Snore Australia.
Existing treatments include masks which pump air into the lungs at continuous pressure and devices which use vibrations to discourage patients from sleeping on their backs.
The mouthpiece, designed in partnership with dental company Oventus, could also help prevent snoring.
- AAP