View full lesson: http://ed.ted.com/lessons/what-causes-cavities-mel-rosenberg

When a team of archeologists recently came across some 15,000-year-old human remains, they made an interesting discovery: the teeth of those ancient humans were riddled with holes. So what causes cavities, and how can we avoid them? Mel Rosenberg takes us inside our teeth to find out.

Lesson by Mel Rosenberg, animation by Andrew Foerster.