Japan Team Regenerates Fully Functioning Mice Teeth

Tokyo, Aug. 4 (Jiji Press)--A Japanese team has successfully
regenerated almost perfect teeth in mice for the first time in the world, a
technology that could make false teeth unnecessary.
"We propose this as a model for future organ replacement therapy,"
the team, led by Tokyo Medical and Dental University Prof. Takashi Tsuji,
said in its report published online Tuesday by the scientific journal
Proceedings of the National Academy of Sciences.
According to the report, the group, which also included members
from Tohoku University and Tokyo University of Science, bioengineered tooth
germs, or tooth buds, from cells taken from mouse fetuses.
The germs were transplanted into the upper jaw sockets of adult
mice, from which molar teeth had been removed.
In about 50 days, the germs developed into fully functional teeth.
Even though the regenerated teeth were smaller than ordinary ones,
their structures were proper and the mineral tissues were as hard as
ordinary tissues.
The team confirmed that the teeth work in step with the
tooth-bearing bones and that the nerves inside the teeth properly transmit
pain and other signals to the brain.
As of spring this year, the regeneration technology had been tested
on 60 mice. The team succeeded in developing fully functional teeth in 34 of
them.
Following the success with teeth, the researchers will move on and
use the same technology to try and regenerate hair.
Tsuji also serves as an executive of a venture firm created last
year by Otsuka Chemical Co. and is trying to establish commercial
applications for the technology.
Hayato Oshima, professor at Niigata University's Graduate School of
Medical and Dental Sciences, said the achievement is significant because it
shows regenerating teeth is technically possible.
But the biggest challenge for the technology's human application is
how to procure stem cells that will develop into teeth, he said.
Even if induced pluripotent stem cells become available, ways to
properly guide iPS cells' differentiation need to be found, Oshima added.
END