Dental fillings are used to treat cavities and to help prevent further tooth decay. Materials used for fillings include an amalgam, porcelain, a composite resin (tooth-colored fillings). Dental amalgams have been used since the 19th century. They are composed of a mixture of silver, tin, copper and mercury.
Composite fillings, first introduced in the 1960's have undergone many generational improvements and are now both strong and cosmetic alternatives to silver mercury fillings.
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