<unk>  A<unk>  or rubber<unk>  is a thin, square sheet, usually latex or nitrile, used in dentistry to isolate the operative site (one or more teeth) from the rest of the mouth. Sometimes termed "Kofferdam" (from German), it was designed in the United States in 1864 by Sanford Christie Barnum. It is used mainly in endodontic, fixed prosthodontic (crowns, bridges) and general restorative treatments. Its purpose is both to prevent saliva interfering with the<unk>  work (e.g. contamination of oral micro-organisms during root canal therapy, or to keep filling materials such as composite dry during placement and curing), and to prevent instruments and materials from being inhaled, swallowed or<unk> aging the mouth. In dentistry, use of a rubber<unk>  is sometimes referred to as isolation or moisture control.<unk> s are also used for safer oral sex.
Dental dam
Birthing chair
Condom machine
Blood lancet
Hot water bottle
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Surgical mask
Baby cage