Yes, the dr. is an oral surgeon. He said in 27 years he did see something like this air bubble as he called it, only a couple of times. It's the upper jaw, above tooth #5, root canaled 20+ years ago. But he said he doesn't see anything to worry about, no infection. He said it can be felt in my mouth, where the gums and cheek meet as a little "bump". My sinuses and everything else looked ok.