I don't know if he's cheap, but Dr. W. Adams in Indianapolis is an Endodontist who "specializes" in cavitations, said a prominent Indianapolis MD. He told me about him, saying it was important to get a bone scan. He may have even mentioned a dye injection.
There's a very prominent dentist in NYC, M. Cortes who--I believe-- uses lasers to treat the bone, I believe in place of drills or cutting tools, and this appeals. But her website and nororiety screams "expensive." But check her out.
I will send you her website in a private message. I think another member said to keep practioner's contact into and names on the d/l.