Recently, a friend posted on Facebook that she was thinking about getting braces, and was feeling unsure because of the fairly common belief that "adults with braces are creepy."
I think this attitude is classist and unfair. The assumption behind "adult braces are creepy" is "braces are for kids." This is classist because it means "your parents should have been able to afford expensive orthodontics for you." That's pretty harsh- a criticism not of you yourself, but of your family and class. When you were a child, no less. You could not have had less control over those factors.
It's also a double bind because adults with severely crooked teeth who DON'T get braces also become the subjects of ridicule. We even have stereotypes associated with very crooked teeth (think "backwoods hick," etc.). Adults with slightly-to-somewhat crooked teeth may not get mocked, but still don't meet our beauty standard. So really, you'd better get your teeth straightened as a kid-- something you likely have no control over-- or you're doomed to be considered ugly in one way or another.
When I see adults with braces, I think it's likely that their families couldn't afford them when they were kids, and now they're doing well enough that they can afford them themselves. That's a generalization, of course, it's just been true (and I do realize this is very anecdotal, but hear me out) of all the adults with braces I've known, and it'll be the case with me if I eventually get any orthodontic work. I think it's cool when adults have braces because it means that they're probably doing better for themselves than the previous generation of their family was. Something something American dream something something.