If that could be targeted at a given tooth site (i.e. I don't want to go thru another round of deciduous teeth across my entire mouth) that would be pretty cool. We're each carrying a perfect growth matrix for new teeth, after all.

If it just repeated the process everyone is already familiar with, in which each of your teeth falls out and grows back in one at a time over a period of several years, it would already be a perfect solution to tooth decay and demand would be massive.