I got braces (and headgear!!!) as a kid-- but I was 13. We talked about it beforehand, discussed my responsibilities in caring for them, etc. I definitely wanted them.
I had "vampire fangs" and my last molars were very far forward in my mouth, which was doing some funky things to my chewing habits and jaw alignment, too. And my understanding is that overlapping, funky teeth are at higher risk for cavities? I'm not sure if that's true.
The dentist asked if I wanted the bottom row straightened. I said no, since they were never half as bad as the top row and aren't really visible. He agreed it wasn't important to have them straightened.
So I really had a lot of say in what happened with my own teeth, and am still very pleased with them today. If I hadn't wanted braces or been unwilling to handle the responsibility of keeping them clean, wearing the dreaded headgear, etc, nobody could force me to keep up the program. It was all under my own steam.
In the end, the braces helped my chewing, posed very little risk to my health, and resulted in a nice even smile. The bottom teeth aren't gonna get me into the Dental Hall of Fame, but I'm very pleased with my own informed decisions as a teenager.
With guidance from a professional and my parents, of course.