What is a dental dam primarily used for?

A dental dam is primarily used as a barrier during dental procedures. It serves to isolate a specific area in the mouth, allowing for more effective treatment while keeping the area dry and free from saliva. This isolation helps in various dental procedures, such as fillings, root canals, or extractions, by providing a clean working environment. Additionally, it helps prevent contamination from the oral cavity and minimizes the risk of the patient swallowing dental materials or tools.

The other options do not accurately reflect the primary function of a dental dam. While preventing tooth decay is essential to dental hygiene, a dental dam does not directly contribute to this outcome. Improving dental aesthetics is more related to cosmetic procedures rather than the use of a dental dam. Similarly, while teeth whitening is a popular cosmetic procedure, it is not related to the use of a dental dam, which is focused on procedural isolation rather than aesthetic enhancement. Thus, the primary role of a dental dam is indeed to act as a barrier during dental procedures.