Dawn, here is the one I did. Also very good I believe and I also emailed with the guy who runs it "Walter Clifford" and he is very knowledgeable. He has no afflilation for particular materials/companies, but will just tell you like it is and he's aware of what is contained in them also.

Here is a link to their site and you can have a read of the options on the left if you wish to know more:
http://www.ccrlab.com/index.php?opt...sk=view&id=40&Itemid=308

And here is another link on the Holistic Dental Network which shows information/research/researchers on these things and more.
http://www.holisticdentalnetwork.com/products_services.php