This. I think every culture has beauty standards, and some of them inspire a lot of people to do pretty drastic procedures. It’s pretty mainstream in America to covet straight, gleaming white teeth.

I’m guessing there’s some long history of orthodontics in USA that intersects with phrenology, marketing to people’s low self-esteem, and piggy-backing on government and orgs’ campaigns for dental health (extrapolating from medical necessity to aesthetics.)

Also I think there’s a weird thing where parents are paying for braces for their kids. Notionally parents want their kids to be confident, but I also sense an undercurrent of social signalling of wealth and status, along the lines of putting solar panels on the north roof of the house if that’s where the neighbors will see them.