20 years ago I had an onlay performed. While I had the temporary on, I broke it off and chewed for several days with no real pain. About the time of the perm onlay, I started to get a pinching sensation of the gum between 2 teeth. 2 dentists have been unable to diagnose the problem, as no redness or swelling. The pain has gotten continually worse over the years. To make matters worse, I had facial shingles 6 weeks ago and the pain now is close to unbearable, but still no redness or swelling. My upper left jaw is numb except for the one area of pain. Any guesses?