Unicode's Miscellaneous Technical block encodes a bunch of dentistry symbols:
⎾⎿⏀⏁⏂⏃⏄⏅⏆⏇⏈⏉⏊⏋⏌
It looks like the first and last two are used in Palmer notation. What are the rest of them used for? What do the circle, triangle, and tilde mean?
1 Answer
According to Dental Computing and Applications, in Chapter XVII on Unicode Characters for Human Dentition,
A triangle with a bar indicates an artificial spacer, especially on a denture, a circle with a bar indicates a supernumerary tooth, and a tilde with a bar indicates an abbreviation for a group of teeth.
It also says that this is notation used by the dental insurance claim system in Japan.