Japanese researchers have grown the first-ever fully functional bioengineered tooth inside the mouth of a mouse.

Bioengineered tooth germ grows into mouse tooth --
Grow new teeth - Mouse shows off bioengineered molar (glowing green)

The bioengineered tooth, which was grown in place of a lost molar, has the same properties of the old tooth and is strong enough to allow the mouse to chew food normally.

To create the new tooth, the researchers -- led by Tokyo University of Science professor Takashi Tsuji -- took epithelial cells and mesenchymal cells (about 50,000 each) from a mouse embryo and cultivated them together in a collagen-based medium to create a tiny tooth bud -- a mass of tissue that has the potential to develop into a tooth.

They then implanted the 0.5-mm tooth bud into the jawbone of an adult mouse in place of a lost tooth. After 37 days, a new tooth sprouted, and after 50 days, it had grown to the same height as the adjacent teeth. The bioengineered tooth has the same hardness as ordinary teeth and it contains blood vessels and nerves, making it sensitive to external stimuli and pain, according to the researchers.

This research is expected to advance the development of "tooth regenerative therapy," which may one day allow doctors to replace diseased or damaged teeth with bioengineered teeth grown from stem cells such as induced pluripotent stem (iPS) cells. This type of treatment could ultimately eliminate the need for dentures and false teeth.

[Source: Yomiuri, PNAS]