Do you have any other crowns? I learned I need to really get the old crowns out too because there could be amalagm under them. Yeast and mercury. There is a strong connection. Yeast/mercury, thyroid. All effected. Mercury can be at the bottom of the pyramid. It is a bit of a mystery for us all to figure this stuff out. You should test for heavy metals. Do the Doctors Data Hair test. If your mouth is 100% free of amalagm, maybe look into a urnine challenge test.