Usually when you picture oral health care from days of yore, something like this comes to mind:
"Ten florins says I can get a loogie into his mouth from here."
Enlisting friends to hold you down and/or beat you with sticks while a barber (yes, a barber, not a dentist -- see the scissors in the background) twists out the rotten tooth with sheer muscle power. If you were lucky, your friends had some alcohol on them and the kid holding a lit candle to your face didn't trip. If you were unlucky, well, your gaping gum hole probably got infected and you died. But the barber could trim up your beard before your family identified the body, so that was good.
Which was why sporting even half a mouth of teeth by age 30 wasn't just a major accomplishment, it would have been a miracle. After all, the smartest people in the world believed tooth decay was caused by a "tooth worm" squirming around and beating the shit out of your tooth nerves for the fun of it.
Luckily, we now know that they're caused by tooth demons.
The sophisticated techniques they have today like root canals (where they can use precision instruments to carefully extract the nerve from inside the tooth) would have seemed like goddamned magic to these savages.
Actually, despite thinking there were literal worms jacking up their tooth holes, someone in 200 B.C. figured out how to perform root canals. We know that because archaeologists found the remnants of the procedure in the jaw of a Jordanian soldier.
Via Clinical Endodontics: A Textbook
Along with these ancient X-rays.
Keep in mind, in order to perform this procedure, the dentist has to understand what the inside of the tooth looks like, whether it's worth hollowing out and preserving, or if it would just be better to pull the bastard out. So when an Israeli archaeologist noticed a green stain on a tooth of the skull of a soldier buried in a mass grave from 200 B.C., he probably thought he was just looking at some particularly stubborn plaque.
It was not.
He was looking at the stain from a copper wire one-tenth of an inch long, which had been inserted into the soldier's tooth, probably in order to deaden the pain of the three apparent abscesses and probable cyst later found by a dental anthropologist (which is totally not a made-up career, by the way). In all likelihood, when the ancient dentist pulled out the nerve from the tooth, he thought he was pulling out the "worm." Either way, in the process he performed a full on modern day root canal.
Just taking a wild guess here, but we're betting it looked nothing like this.
We can only hope the afflicted soldier appreciated him for it.
For more ways modern society is behind on the learning curve, check out 6 Amazingly High-Tech Ancient Weapons and 6 Modern Technologies Animals Invented Millions of Years Ago.