Root canal is one of the last ways to save a decaying tooth and it is only used if the tooth has experienced sever decay and/or the nerve of the tooth is almost/already exposed. This requires immediate treatment as it can cause any if not a combination of the following symptoms, irritation, inflammation, sever pain, infection, sensitivity and advanced gum disease.
Root canal starts with the removal of the affected nerve and then the hole where the nerve was is filled up and the tooth around it is rebuilt using composite. The procedure itself is not painful as local anethetics will be used to "freeze" the tooth prior to the root canal. Post procedure the tooth may also need a crown on top of the tooth afterwards to keep it intact.
Prices of root canal treatment depends on number of roots of the affected tooth and if a crown will be needed post procedure, our dentists will talk to you about prices and required procedures before treatment. This procedure is financially costly so routine checks are essential to keep and spot minor cavities before they become major.
After the procedure a crown also needed in order to protect the tooth from shattering, more information on the crown/bridges page.