You're not really channeling Carrie Bradshaw in a discussion about outward appearance and self-acceptance, are you?
Fugly is subjective. I find a lot of what fashion/style experts recommend to be fugly.
Inappropriate, yes, depending on the occasion, and particularly in a job situation, people should dress accordingly because that affects their livelihood and well, people do have to make money to support themselves.
As for teeth, I actually hate that society puts so much pressure to have perfect teeth. There are people who quite simply can't afford to get their teeth fixed. They have no choice but to live with that. The onus should be on society to get the hell over it instead of making someone feel bad for something they can't fix.
Now, if you have really funky breath, you should take care of that because it affects others.