Dental inactivators, also known as pulp inactivators, work by causing necrosis of the dental nerve, which usually results in pain relief for the patient. The main ingredient in a typical pulp inactivator is paraformaldehyde, which is placed primarily in the pulp cavity and acts on the nerve to slowly necrose the nerve. The patient will return for treatment in 7 to 14 days. This will reduce the patient’s pain while the nerve is being removed. There are also some pulp deactivators that can rapidly necrose the nerve, the main ingredient being arsenic trioxide. Typically, dental inactivators need to be removed after they have been sealed for about 48 hours or they can easily damage the tooth. If the pulp inactivator leaks, it can easily burn the periodontal mucosa. Patients are advised to use dental pulp inactivator under the guidance of a medical professional to avoid adverse consequences.