Dental dam

A thin, rectangular sheet used in dentistry to isolate the operative site

A dental dam or rubber dam is a thin, 6-inch (150 mm) square sheet, usually latex or nitrile, used in dentistry to isolate the operative site from the rest of the mouth. Sometimes termed "Kofferdam", it was designed in the United States in 1864 by Sanford Christie Barnum. It is used mainly in endodontic, fixed prosthodontic and general restorative treatments. Its purpose is both to prevent saliva interfering with the dental work, and to prevent instruments and materials from being inhaled, swallowed or damaging the mouth. In dentistry, use of a rubber dam is sometimes referred to as isolation or moisture control.

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