Root canals have had a bad wrap. Why? Because the longer a "bad" tooth has to wait before getting treatment, the worse the infection in the area. Sometimes, you may have an infection or abscess and not be able to feel it. Sometimes it shows up on an xray. Or, sometimes, the diagnosis for a root canal is based on other symptoms such as tenderness on chewing, lingering pain because of thermal stimulus, spontaneous pain, or the diagnosis of a crack, among others.

Dentists and Endodontist do several tests to verify that a tooth actually needs a root canal. These include tapping on the tooth and testing the tooth with thermal and electrical stimulus to assess whether the tooth's nerve is going bad. Sometimes a bite irregularity can cause the same symptoms as an infected tooth. Therefore, it is important to make sure that the tooth that is going to have a root canal actually has a "bad nerve".

Special note: If a root canal is the result of a cracked tooth, it is important to assess the severity of the crack. Sometimes, the crack that is causing the discomfort extends below the tooth into the surrounding gums and bone. As a result the patient may get partial relief or no relief from a root canal. Severely cracked teeth should be taken out. Your dentist or endodontist will do the best they can to assess the severity of the crack. You should decide based on the information relayed to you whether you want to continue with the root canal or take the tooth out and replace it.