People don't bleach their teeth much outside the US as far as I know. You can see it especially well with US actors, their teeth looking like the someone photoshopped them to #FFFFFF

Others note the bleaching, which is relatively low cost, but the (purely cosmetic) straightening is probably the more interesting example.

People in the US pay a lot of money to have very straight teeth. You can see this clearly with American celebrities and actors (versus European counterparts), but the culture of cosmetically modifying teeth is very strong all across "middle class" and up America as well.

Way more people having their teeth whitened? Braces being more popular.

Bleaching your teeth, specifically.

US people wear facades to hide their teeth.