It's also because medicine and dentistry evolved separately. Dentistry started more as a kind of "mechanic"-type profession of rather crude surgery (of course,

It's also because medicine and dentistry evolved separately. Dentistry started more as a kind of "mechanic"-type profession of rather crude surgery (of course, all surgery was quite crude before modern times), and was often a sideline of other professions (e.g. dentures were made by jewelers and other types of craftspeople). By the time dentistry started to turn into a serious medical discipline in the 1800s, the existing branches of medicine didn't want anything to do with it. So dentists founded their own medical schools, developed their own licensing boards, and so on. By the early 1900s, dentists were so used to being separate that they actually actively lobbied against any attempt at unifying medicine and dentistry. There's a good article in The Atlantic about it: "Why Dentistry Is Separate From Medicine" [1]. [1] https://archive.ph/4HIxk https://archive.ph/4HIxk