A multi-national research team headed by USC School of Dentistry researcher Songtao Shi, successfully regenerated tooth root and supporting periodontal ligaments to restore tooth function in an animal model. The breakthrough holds significant promise for clinical application in human patients.

The study appears in the Dec. 20 issue of PLoS ONE.

Utilizing stem cells harvested from the extracted wisdom teeth of 18- to 20-year olds, Shi and colleagues have created sufficient root and ligament structure to support a crown restoration in their animal model.

The resulting tooth restoration closely resembled the original tooth in function and strength.

The technique relies on stem cells harvested from the root apical papilla, which is responsible for the development of a tooth’s root and periodontal ligament.

Previous studies conducted by Shi and collaborator Stan Gronthos at the National Institutes of Health had utilized dental pulp stem cells. Shi found the new technique to be superior.

"The apical papilla provides better stem cells for root structure regeneration. With this technique, the strength of the tooth restoration is not quite as strong as the original tooth, but we believe it is sufficient to withstand normal wear and tear," says Shi.

He hopes to move the technique to clinical trials within the next several years, a potential boon for dental patients who are not appropriate candidates for dental implant therapy or would prefer living tissue derived from their own teeth.