Question: why do our teeth fall

Reka Nagy answered on 16 Nov 2016:

We have two sets of teeth – baby teeth (also called milk teeth) and grown-up teeth. The main reason we start out with two sets is that initially, a baby’s mouth is not big enough to fit a full set of teeth. So initially they start growing a smaller set, which is also necessary to make sure that your grown-up teeth will grow in the right place and your jaw will develop properly.

As for why they fall out, and how they know to do so – that’s because we are born with both sets of teeth, but the grown-up teeth are initially deep in the jaw. As we grow, they start pushing up through the jaw, displacing the milk teeth by destroying their roots. Since they have nothing to hold on to your gums with, your milk teeth will fall out!