Meth mouth

Ever notice that county patients have really, really lousy teeth? When I was on the wards, I never really put two and two together but the dentists all seem pretty clear that a lot of it is meth mouth. Here's how they break it down:
Meth makes your mouth dry
Dry mouth makes your plaque germs happy
Ta daa! Meth mouth.

Apparently, it's very, very fast, too: folks who start in their teens and twenties end up ready for dentures by age 40...