I had two cavities when I was younger (ten-ish, I think,) in my lower back teeth. They are now nice and filled.

The rest of my teeth were a mess; there were teeth I was missing, I had doubles of certain ones, baby teeth that never came out (still haven't), and so forth. Three years of braces and orthodontist visits sorted it out, but they still look awful (they are smaller at the bottom than at the top, making the appearance of spaces between my teeth-- or like I see it, candy-corn teeth) and I have to wear a retainer every night.

I also have a permanent metal wire retainer glued to my bottom teeth, which is awesome, because it makes me a cyborg. :3