An indirect pulp cap is usually done to take the place of a root canal in very decayed teeth. It is made when most of the decay on the permanent tooth is removed. When a dentist finds extensive decay very close to the pulp (nerve,) the risk of the pulp exposition by the infected decay is high. This infection will result in the need for a root canal. In this case dentists leave the last little bit of decay in there and place a sedative temporary filling. Usually Intermediate Restorative Material (IRM) is used as a temporary filling material until the patient is ready for a proper, more permanent restoration.
