From Scientific American:
Stem cells from pulled teeth regenerate new roots, might some day replace dental implants. For Christmas, a few miniature pigs in a University of Southern California lab got new roots for their front teeth, courtesy of stem cells from human teeth. This regeneration of mammalian tooth root, reported in last week’s inaugural issue of PloS ONE, could have clinical applications that would have a big impact on oral surgery procedures such as root canals.
An international team headed by dentistry researcher Songtao Shi focused its efforts on stem cells found in the root apical papilla, tissue connected to the tip of the root that is responsible for the root’s development. Previous efforts by Shi and his colleagues involved the harvesting of stem cells from the dental pulp, the tissue at the center of a tooth, commonly referred to as the nerve.
More here.