Perhaps the two words most dreaded by dental patients. While the condition that causes root canal is indeed serious, the good news is that the modern procedure to correct the condition is virtually painless. Root canals prove to be necessary when the tooth's pulp (or its "root" which is the interior of the tooth, is damaged to the point where it threatens the life of the tooth if the pulp goes untreated. A root canal involves removal of the diseased pulp, followed by a cleaning and closure of the canal that housed it (thus the procedure's name). A dental crown is then placed over the repaired tooth, and the patient's healthy smile is kept intact.