In the results of an unexpected study, a team of scientists from China showed that it's possible to grow rudimentary teeth out of human urine.

Urine byproducts, the study found, can be used as a source of stem cells that can produce tiny tooth-like structures. The results were published in the Cell Regeneration Journal.

For the study, the group of scientists from Guangzhou Institutes of Biomedicine and Health coaxed cells normally discarded in waste like urine into becoming pluripotent stem cells (iPSCs). They then implanted those cells into the jawbones of mice.

After three weeks, the cells grew into a bundle of cells that resembled a tooth, containing dental pulp, dentin, and enamel space and enamel organ.

The new teeth, however, were one-third the hardness of human teeth. Some stem cell researchers cautioned the process still faces many challenges.

Yet, the results of the study may be an auspicious start for the process of growing new teeth, which people can lose for a host of different reasons from accidents to diseases.

Urine is "probably one of the worst sources" for the type of cells that can be turned into stem cells, Professor Chris Mason of University College London told the BBC.

"There are very few cells [in urine] in the first place and the efficiency of turning them into stem cells is very low," Mason said. "You just wouldn't do it this way."