What's the history as to why braces for aesthetically imperfect but fully functional teeth are deemed normal (or even a rite of passage), while other cosmetic procedures (e.g., hair transplants/rhinoplasties) aren't? Was it ever seen as "weird" to have had one's teeth straightened by braces?

by JJVMT

Also, was there ever a time in the 20th century where people whose teeth had been straightened by braces might not want to admit it publicly?

klew_52

Also if I can add to this, what is the history on why braces are covered by insurance, yet other cosmetic procedures are not.