Finally, a study with some teeth to it.

Scientists say they've discovered a gene that may some day allow for the growth of replacement teeth in a laboratory setting, according to a study published in this week's Proceedings of the National Academy of Sciences.

The gene, called Ctip2, was already known to have several functions in immune response and the development of skin and the nervous system. Scientists say the gene could also be used to grow tooth enamel — the hard outer portion of teeth.

"It's not unusual for a gene to have multiple functions, but before this we didn't know what regulated the production of tooth enamel," said Chrissa Kioussi, an assistant professor in the College of Pharmacy at Oregon State University, in a news release. "This is the first transcription factor ever found to control the formation and maturation of ameloblasts, which are the cells that secrete enamel."

Scientists had already discovered ways to grow the inner portion of teeth in laboratory animals, but had lacked the means to grow enamel, which protects teeth from breakage.

"Enamel is one of the hardest coatings found in nature, it evolved to give carnivores the tough and long-lasting teeth they needed to survive," Kioussi said.

Scientists tested their theory in laboratory mice by "knocking out" the Ctip2 gene and found that when this gene was blocked, mice grew rudimentary teeth that did not contain enamel.

"A lot of work would still be needed to bring this to human applications, but it should work," Kioussi said. "It could be really cool, a whole new approach to dental health."

The study's authors say the research may make it possible for researchers to grow new teeth for people who have lost them to damage or disease.