Lemonparty.org: However, no one mentions your teeth. You only get a single set of adult teeth, and after 1000 years of wear and tear, even teeth with good hygiene will be worn way down.
I always said that even if we were perfect, our teeth and knees would wear out. Some JWs would say "but your teeth will be perfect". I would say that being "perfect" doesn't mean they're made out of some indestructible material; they'd still be made of materials that would wear out. You keep rubbing two "perfect" teeth together and eventually they're going to wear down. JWs would say that Jah would keep them from wearing down.
Everyone that I always spoke to about teeth said that we would regrow teeth every so often. There are examples of that happening today. While it's not common and is most likely a genetic defect, it has been documented.