Wouldn't it be cool to just grow new teeth instead of having to rely on crowns, dentures, and other substitutes? Thanks to the work of researchers at the Tokyo University of Science in Japan, that may soon become possible. As Science reports, cell biologist Takashi Tsuji and his team have successfully grown new teeth in mice:
The Japanese group . . . focused on tooth germs, the embryonic tissues that develop into teeth. After obtaining such germs from mouse embryos, they separated out two types of cells--epithelial cells and mesenchymal cells--and then recombined them into a new bioengineered tooth germ. (Tsuji says that he and colleagues wanted to demonstrate that, for future human clinical applications, they could likely start with epithelial and mesenchymal cells derived from a patient's own stem cells.) The team then grew the bioengineered germs in a special culture for 5 to 7 days and transplanted them into the upper jaws of adult mice in the place of an extracted molar. New teeth poked through the gums after about 36 days and reached the proper size and alignment with opposing teeth for proper chewing after 49 days.
Science adds that the teeth function "just like the real thing," with roots, pulp, and enamel equivalent to those of regular teeth. Also, since the new teeth bind themselves to the underlying bone and nerve fibers, they should allow subjects to feel "chewing pressure and other stresses."
There are caveats, though. According to Science, "the crown widths, cusp positions, and tooth patterning were not quite normal." However, Tsuji reportedly expects his team to control those attributes "with further research."