Which instrument is commonly used to invert a rubber dam?

The instrument commonly used to invert a rubber dam is a plastic instrument. This tool is designed specifically for manipulating and placing the rubber dam material effectively, ensuring that it is properly adapted around the teeth.

The key function of the plastic instrument in this context is its ability to smoothly invert the edges of the rubber dam into the gingival sulcus, which provides a better seal and prevents saliva contamination during dental procedures. The tip of the plastic instrument has a suitable shape and flexibility that allows dental assistants to position the rubber dam without damaging the material or irritating the surrounding soft tissues.

In contrast, while a metal spatula and a dental explorer have their uses in various dental procedures, they are not preferred for inverting a rubber dam due to their rigidity and potential to damage the rubber material or injure the gums. Similarly, a composite instrument, intended primarily for handling composite materials during restorative procedures, does not provide the appropriate design needed for the specific task of rubber dam inversion.