NEW YORK — I looked inside and there it was: dark and deep, a gaping gray pit. As the dentist spoke, I couldn’t process the news. My 8-year-old son had his first cavity, and it’s “quite large,” he ...

I looked inside and there it was: dark and deep, a gaping gray pit. As the dentist spoke, I couldn’t process the news. My 8-year-old son had his first cavity, he confirmed to this disbelieving mother.

We’ve all heard the scary stories about cavities. Those little holes in your teeth that cause pain and sometimes lead to bigger problems. But there’s also plenty of confusion around how cavities work.

The astonishingly well-preserved nasal cavity of a Neanderthal in Italy has finally settled one of the great debates in ...