content: I wish someone would put a billion into stem-cells to regrow teeth. If we have the ability to grow skin from stem cells etc., the same should be able to be done with teeth. That's really the future.  There was also some stuff a few years ago about turning off the gene that causes your body to make the mouth acid that eats bacteria that in turn eats your teeth. The idea was we don't need that now because we have toothpaste, so by switching that off our teeth would never rot.