6. It shouldn’t hurt—at first
Cavities, in the early stages, should not hurt at all. If you get regular checkups with X-rays, your dentist should be able to nab any cavities at an early stage and do a quick filling. It’s only when the decay goes very deep into a tooth’s roots and presses on nerves that you need a root canal, a surgical procedure where a dentist removes that nerve while filling the roots of the tooth.