Teeth replacements grown

Researchers from the Tokyo University of Science, Tohoku University, and Tokyo Medical and Dental University have grown the world's first fully functional bioengineered teeth in mice, using dental seed tissue transplanted into their jawbones.

To grow a tooth replacement, the researchers, led by professor Takashi Tsuji of the Tokyo University of Science's Research Institute for Science and Technology, first extracted and cultivated epithelial cells and mesenchymal cells from a mouse embryo. Once these cells developed into a tooth germ -- a seed-like mass of tissue containing the cells and instructions necessary to form a tooth -- the researchers transplanted it into the jawbone of an adult mouse in place of a missing molar.

After 37 days, the new tooth began to grow, and after 50 days, it had developed to the same size as the adjacent teeth. The bioengineered tooth had the same hardness as ordinary teeth and was strong enough to allow the mouse to chew food normally. In addition, the replacement was complete with blood vessels and nerves, making it sensitive to external stimuli and pain.

According to the researchers, the technique could eventually lead to alternatives to dentures or dental implants, and may also be applied to internal organs and other body parts.