What does a cavity on an xray actually look like?
If you've ever sat in that stiff dentist chair and stared at a grainy black-and-white screen, you probably wondered how your dentist can spot a tiny cavity on an xray among all those blurry shadows. It's a bit like looking at a Rorschach test, isn't it? One person sees a butterfly, the other sees a inkblot, and the dentist sees a three-hundred-dollar filling. But there is actually a lot of science behind those little grey blobs, and once you know what you're looking for, it's not as mysterious as it seems. ...