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Tooth Decay

Tooth decay is the commonly known term for dental caries, an infectious, transmissible, disease caused by bacteria. The damage done to teeth by this disease is commonly known as cavities. Tooth decay can cause pain and lead to infections in surrounding tissues and tooth loss if not treated properly.


  • Brush teeth twice a day (with a fluoride toothpaste).
  • Floss every day.
  • Eat snacks that contain less sugar.
  • Put dental sealants on tooth surfaces.

Dental Fillings

Dental amalgam

Dental amalgam is the silver-colored material used to fill (restore) teeth that have cavities. Dental amalgam is made of two nearly equal parts: a powder containing silver, tin, copper, zinc and other metals, and liquid mercury.

Dental amalgam has been used to fill cavities for over 100 years. It is easy to use, strong, durable, and relatively inexpensive.

Some people are concerned that the mercury may cause health problems. In September 2006, an advisory panel to the U.S. Food and Drug Administration (FDA) reviewed FDA’s research and heard presentations from the public about the benefits and risks of mercury and amalgam. The panel generally agreed that there is no evidence that dental amalgams cause health problems in the majority of the population. However, their effects on pregnant women, small children, and people who are especially sensitive to mercury are not clear.

Other Types

Resin composites are tooth-colored materials made from powdered glass and resin compounds. When composites were initially introduced, they were not very strong and were used primarily in the front teeth. Newer composites are stronger, although they still tend to wear more than metal-based materials and generally need earlier replacement.

Glass ionomer cement is also a tooth-colored material. It is not usually used for long-term fillings because it breaks easily.

Porcelain, gold, and other metals are also used as filling materials. Gold and porcelain are used for inlays, veneers, crowns, and bridges. These fillings are made outside the mouth and cemented into place after they are formed.



U.S. Food and Drug Administration