I'm curious if and how people cleaned their teeth prior to the 20th century. Any time or place would be interesting.
P.S.: I'm sorry if this is in the FAQ. I'm on my phone and have trouble accessing it from there.
In Arabia they used (and in some cases continue to use) a stick called a miswak that you sort of chew and scrape your teeth with. It features pretty prominently in the hadith as a good hygiene practice for Muslims.