Here's a facinating article that shows that ultrasound waves may help in regenerating and repairing dental tissue. I've seen different versions of this article saying that treatment times are as short as 20 minutes/day over 12 weeks (I'll try to verify this). Can growing teeth in total be far behind?
Here's the link
My kudos to the researchers at U of Alberta, fantastic work!
Hans Skariah, B.Sc., DMD