got this info from a email list I'm on. So i've put a few different posts here related to the subject
Warning about Glass Ionomer
Cement Dentists use to fill cavities and for dental restoration, the non silver type. They contain fluoride which is released slowly over a long period of time.
http://en.wikipedia.org/wiki/Glass_ionomer_cementComposite fillings are not glass ionomer, although glass ionomer is used for some fillings. The materials are numerous and you should ask the dentist what type of composite fill he used and then look up the ingredients.
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