Why do Asians have bad teeth?

It seems like a lot of girls from Asia, even "modernized" countries like Japan, don't really take care of their teeth or something, while Asian-American girls seem to have much better teeth.  Why is this, I wonder?

Japan doesn't have fluoride. AT ALL.  In North America, it's in the water, it's in the toothpaste, it's in your mouthwash, it's EVERYFUCKINGWHERE.  In Japan, not at all.  So even if they brush like the fucking brushing... brusher... thing... they'll still be behind an American kid who brushes irregularly, because of the fluoride issue.  I've been here a year, and my teeth have gotten noticeably less good, due to the lack of fluoride...