Bizarre Problem with Chronic Tooth Pain

Hi,

I have been experiencing pain in various teeth for over a year now. The pain is usually around my upper molars, usually the left side, but sometimes the right, rarely both, and is localized to the general area of the molars and is best described as feeling like "inflamed" gums, but aparently they are not inflamed. The pain eminates outward and into my jaw around the area. When the pain is present, the teeth and gums in the area seem to have a very metalic taste.

All upper molars have fillings, some old (+20 years) and some new. The fillings on the left uppers are a mix of composite and amalgam, the right uppers are mostly Amalgam and some composite.

The pain is light/non-existent in the morning and peeks around noon, but generally always present. Some weeks are far worse than others. Topical Oragel provides slight temporary relief, however, a direct shot of novacaine in the area had no effect. 400mg Advil seems to help a lot, but the pain usually returns, albeit less so. I also suffer from frequent headaches which compounds/confuses the problem.

The teeth are not sensitive, although I started using sensitve paste. I had a mouth gaurd made, that didn't help. There are no more cavities to be found.

I have seen two separate dentists, and they are both stumped. One recommended a root canal, the other didn't want to be too hasty as I can't declare a single problem tooth on either side and the pain swaps from side to side without rhyme or reason.

I am 34 years old, take Nexium daily, but otherwise am in good health. I work with computers all day, and have for a decade. I believe the monitors cause the headaches, but not the tooth pain.

Any ideas?