If an accidental pulpal perforation occurs during the repair of a cavity and the diameter of the perforation is less than 0.5 mm, a pulp protector can be used to cover the perforated hole to promote calcification of the adult dentin cells and the formation of restorative dentin, and the cavity can be repaired without significant pain to preserve the healthy pulp. In the case of trauma to a young permanent tooth, local anesthesia can be used to remove the crown pulp, and calcium hydroxide can be placed in the root canal opening to preserve the vitality of the root pulp and encourage the root to continue to develop. In cases of pulpitis or periapical inflammation with severe pain, the infected pulp is removed under local anesthesia, and the root canal is prepared, disinfected, and filled.