Yes, chelating can take a long time, it took me about a year to come right after I had 13 mercury fillings removed in the 1980's. Removing the mercury fillings was a turning point in my yeast infection too, but when I had it done there were no rubber dams, oxygen or any possible patient protection and I suffered the most horrendous aggravations you could imagine. My dentist retired not long after, he got to sick to continue removing Amalgam fillings and retired only in his late 50's. A hair analysis and urinary provocation test revealed that I was loaded with mercury, but also cadmium, arsenic and lead. Mercury sufferers often collect other heavy metals in their system, as their detox capability declines the more toxic they become.
Make sure you go to a dentist who knows and understands the right mercury protocol, and be sure to follow a good mercury detox protocol. Repeated provocation tests over a prolonged period of time will guide the way. I found Doctor's Data in Illinois to offer the best toxic analysis testing (hair and urinary prov.), based on my 25 yrs in natural medicine.