That was certainly a popular impression in past centuries. In the book Simplicius Simplissimus (1668), the main character takes time off from the 30 Year's War

That was certainly a popular impression in past centuries. In the book Simplicius Simplissimus (1668), the main character takes time off from the 30 Year's War to do some dentistry. He goes from village to village, using show tricks to hide to audiences how painful and damaging his operations are to his customers. EDIT: Some nonfiction: an account of quacks from the 19th century https://archive.org/details/monthylygazette00mdgoog/page/n376/mode/2up https://archive.org/details/monthylygazette00mdgoog/page/n37...