Science Questions

I have two young daughters aged 6 and 8. They’re losing their baby teeth. I’m wondering why the teeth falling out don’t have any roots. Surely teeth have roots. Where are they going? Geoff, Australia

Baby teeth definitely do have roots and I have a painful personal experience to recount on this front.  When I was about 14 my dentist decided that I had too many of my milk teeth left and decided they needed pulling out.  He pulled them out and it was terrifically painful because they all had very long roots.  The ones that had fallen out didn’t have any roots.

The reason is that when you have secondary dentition, or adult teeth, they come up underneath where your baby teeth are and they erode the root away so this loosens the tooth and makes it fall out.  Only once there’s a secondary tooth to come in its place because evolutionarily speaking it wouldn’t do to have a period with no teeth.  If all your teeth just fall out then you’d have nothing to replace them with.  You might starve if you were back in ancient history and didn’t have the welfare start to look after you with pot noodles.  That’s why you have this dissolving of the root in order that the tooth can be replaced by secondary dentition.  What he’s seeing is nature in action.

June 2008