An Overview of Root Canals
Root canal is a form of treatment used to save a tooth that is badly decayed, and destroying the pulp of the tooth. Root canal entails removing the pulp, cleaning up of the inside of the tooth, and then sealing it.
Pulp in a tooth becomes infected, irritated, or inflamed often due to decay, repeated dental procedures, a crack or chip in the tooth, or trauma to the face. It will lead to severe toothache, discoloration and sensitivity.
Root canal therapy should relieve pain and will help you maintain your tooth over a lifetime. However, even the best efforts to clean and seal the tooth may lead to new infection.
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Why do we take them? 
There are three main ways to replace missing teeth