It could vary by area, but according to my Washington DC CCC, in my area it is a prosthodontist. "Fortunately" my insurance policy has no real dental benefits and their reimbursement rate for "preferred provider dentists" is so low, that no dentist we found that we liked in the last 30 years here was one, so an insurance list was not a factor. He limits his practice entirely to oral cancer patients and I've had some nice conversations in the waiting room.
The prosthodontist is exceptionally good if you will need any type of speech prosthesis as I do.
Charm