I knew someone whose father was a dentist in the Pacific during WWII. He didn’t have electricity but he had a corpsman on a bicycle that would pedal to get the drill to revolve. Apparently they didn’t have a lot of or any novocaine.
I got the impression that no numbing agent was used when he said it hurt like hell but this was before he went to the Pacific. Still in the US at that time. The other interesting thing was that they had to eat mostly beans for a week so they could have a XMAS dinner but the day they had the dinner he had to have dental work done. Poor dentist didn’t even have XMAS off...lolol