Although porcelain/ceramic fillings have been used for years, they often contain a substantial amount of aluminum, normally in the form of aluminum oxide. In some cases, they contain 45% aluminum oxide.
Some manufacturers claim that only very minute amounts of aluminum leach from these fillings, however, medical professionals have claimed to have witnessed aluminum toxicity allegedly caused by this type of filling material. The general belief is that aluminum toxicity leads to immune system issues and neurological disorders.
It has also been reported that porcelain fillings contain various other metals such as cobalt, barium and cadmium, each of which can be harmful to your health. Some manufacturers of porcelain fillings utilize chemicals like acrylate, formaldehyde, hexane, hydroquinone, phenol, polyurethane, silane, strontium, toluene and xylene which can be present in the final filling material.
It is well known that mercury and aluminum are extremely toxic to the body when mixed. It may be wise to consider this fact if you believe that aluminum leaches from fillings, especially if you're having Amalgam (mercury-based) fillings removed just prior.
Resin fillings are often thought of as "plastic" fillings. They normally contain a mixture of glass and plastic with other substances.
The health concern associated with resins are that they contain a class of chemicals known as bis-phenol (or BIS-GMAs). This substance has been shown—in some cases—to leach estrogen-mimicking compounds into the body. There are also reports that some brands of resin contain barium and/or aluminum.
Some resins are based on another class of chemicals known as methacrylates and have properties that may make them hard on the liver and kidneys over an extended period of time."
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