Mercury amalgam filling or "silver fillings" is the most commonly used dental filling material in the back teeth and is NOT safe in the mouth. The criteria dentistry used is durability and cost. The criteria should be safety, durability, natural looking, cost, and ease of use by the dentist. Please note that these are all physical and economic reasons for use. No attention is paid to biocompatibility and your health history. In other words, how it impacts you.
Because some people have sensitivity to certain substances, the choice of dental materials may have to be limited. A special blood test from Clifford Consulting & Research at www.ccrlab.com may be utilized to determine sensitivity to corrosion by-products that come off all dental materials in your mouth and then get swallowed into your body. It will show if you have an immune sensitivity and what should not be used and as a guide for what may be suitable.
Some dental materials contain toxic substances which, depending on exposure and other factors, may impact total toxic body load. Non-toxic alternatives should be used to decrease exposure to and accumulation of scientifically confirmed environmental toxins. Some examples are: mercury and silver in amalgam fillings (the black ones in one's mouth).
Some dental treatment and materials can be disruptive to the normal flow of energy through the acupuncture meridians. Eastern philosophy believes chronic disruption of energy flow causes dysfunction and resultant health problems on that meridian; therefore the choice of dental materials and treatments is limited.
Dissimilar metals in the mouth like mercury and silver, including different formulations of the "same" metal, create microamps of current which could cause decay, oral pain, corrosion of the metal (black mercury amalgam fillings), dry mouth, metallic taste, erythema (red & swollen gums). Your saliva is the electrolyte like acid in a battery.