As far as I know, there aren't any known allergic reactions to ceramics but there have been cases of metal allergies. The only way you'll find out if its true is if you switch the materials of the dental crown/cement that are used and find the right combination for you. You may want to ask your doctor for a referral to an allergist to see if that's the case.
I've been to an allergist. He says he doesn't have any way to test for oral allergies. Allergists do patch testing on the back. That is wothless for an oral allergy. He said dentists should invent a device that can put materials in the mouth to test that way. Right now the only thing tha can be done is to spend $1000 on a crown to see if it wors. That's a pretty expensive test.
Like I said in my question - I have found that InLine works. It is fused to captek which has plent of metal in it. That means it is not a metal alletrgy. It is the ceramic that has a terrible taste to me. I am definitely having a reaction to the ceramic.
Unfortunately I'm not aware of any allergy tests for the mouth specifically either. It seems the only way to remedy the problem is to place that particular crown that works for you.
OK, thanks for answering anyway. I had one of the emax crowns removed. In a few weeks the lab should have a captek/inline one made. Hopefully that will feel as good as my 7 other captek/inline crowns. If it does I will have the bridge replaced with the same material.
I really want somneone to write this up in a dental journal. The problem with allergies a lot of times is that people don't believe there is really something wrong. If it happens to someone else they could just look it up and see that it has happened before.
Hopefully that'll solve the problem. If you want to, you may want to see if your local dental school may have a professor who may be interested in writing up your experience.