Could human urine be used to grow new teeth? A new Chinese study says yes.
The research, published in the Cell Regeneration Journal, suggests that human urine could be used as a source of stem cells to grow tiny tooth-like structures known as "tooth buds."
The Chinese Academy of Sciences created new teeth for mice using a similar process and believes bioengineered tooth buds could one day be implanted into the jaws of people who have lost teeth.
More from GlobalPost: Scientists power mobile phone using urine
Scientists did it by coaxing cells normally discarded in waste like urine into becoming pluripotent stem cells (iPSCs), which have been generated into many different cell types, including neurons and heart muscle.
Researchers then forced those cells to mimic the cells responsible for tooth enamel and the three main components of teeth — dentum, cementum and pulp.
That material was implanted into the mice, and, three weeks later, new teeth had sprouted.
More from GlobalPost: Urine-soaked eggs a springtime treat in China
The new teeth were just one-third the hardness of human teeth, however, and some stem cell researchers cautioned the process faces many challenges.
Chris Mason, a stem cell scientist at University College London, told the BBC urine was a poor starting point for stem cells.
"You just wouldn't do it in this way," he said.