Anyone?

A bunch of stuff could be effecting your thyroid, mercury amalgams, fluoride in the water .. etc. You can't say for sure tooth X is causing the problem with your thyroid. That said, all root canals are toxic, if you care about your health it makes sense to remove them.

You just need to find a holistic dentist that does a biological extraction, ie one where they clean the bone surrounding the tooth socket.

Some root canals actually have mercury at the end of them, which is fairly insane.

How did the dentist fill the root canal after emtying it out? Did s/he fill the canal with some sort of compound or did s/he insert a metal post?

If s/he had a lab make a post for you or if you have crowns, ask the dentist what kind of alloy was used to construct the post or crown. The metal used in dentistry should be constructed out of a high quality alloy made out of gold, palladium or platinum or any combination of the above. Small percentage of silver in the alloy is ok but some people's bodies reject even silver.

I was a dental lab technician for many many years and have made thousands of posts and crowns. However half the time the dentist would order the lab to make the post/crown out of cheap quality metal to save money.

If Amalgam or cheap metal was used in your case, this could be your problem. Non-precious alloy used in dental industry can have nickel, beryllium or any other kind of crappy metal in it, which may cause health problems.

Another possibility is that your root canals may have pockets of air left in them when they were being filled by compound or metal, which will cause bateria growth after a while. By pockets of air I mean about 1/10 mm or less.

If you have metal posts or crowns, ask your dentist what kid of alloy it was made of and ask him/her to give you the specifications for it. When I had my own lab, I used to send a metal certificate with each work, that explains the alloy's exact specifications.

The above are a couple of possibilities.