Researchers have now found a way to grow teeth from a person's own gum cells, a finding that can help many replace missing teeth with teeth that are bioengineered.

Previous studies conducted on growing these "bioteeth" have focused on growing immature teeth that resemble teeth found in the embryo (teeth primordial). These teeth are then expected to grow into normal, adult teeth when transplanted as cell pellets in the jaw.

These embryonic teeth primordial, despite being in different environments, grow well in the human mouth. However, sources from which these cells can be obtained are rare and thus can't be utilized for practical purposes.

"What is required is the identification of adult sources of human epithelial and mesenchymal cells that can be obtained in sufficient numbers to make biotooth formation a viable alternative to dental implants," said Paul Sharpe, an expert in craniofacial development and stem cell biology at King's College London, and lead author of the study.

In the present study, researchers isolated gum cells from patients at the King's College London. The cells were then grown in the lab. Next, researchers combined these cells with cells of mice that form teeth.

The experiment led to hybrid human/mouse teeth that had both and enamel and functional root. Current tooth implants don't produce the natural root structure and patients getting these implants experience friction while eating. The constant irritation drives loss of bone around the jaw.

"Epithelial cells derived from adult human gum tissue are capable of responding to tooth inducing signals from embryonic tooth mesenchyme in an appropriate way to contribute to tooth crown and root formation and give rise to relevant differentiated cell types, following in vitro culture," Sharpe said in a news release.

'These easily accessible epithelial cells are thus a realistic source for consideration in human biotooth formation. The next major challenge is to identify a way to culture adult human mesenchymal cells to be tooth-inducing, as at the moment we can only make embryonic mesenchymal cells do this," Sharpe concluded.

The study is published in the Journal of Dental Research.

Adults in the U.S. between ages 20 and 64 have an average of 24.92 teeth remaining, according to data by the National Institute of Dental and Craniofacial Research. About 3.75 percent of adults have no remaining teeth.