Root canal treatment
And endodontist is a qualified dentist (4 years of study) that has also studied 2 extra years to qualify for the highly specialized area of dentistry that deals with the inside of the tooth (called pulp) and the surrounding tissue (endodontics or root canal treatment).
If you notice that one of your teeth has discolored (even though you are not experiencing any pain) or you are experiencing dull aching or severe pain in a specific tooth, you might need endodontic treatment. You might also experience swelling of the gum around the tooth and the tooth might be tender.

If an examination proves that the nerve or blood supply inside the tooth is infected due to decay or injury, your dentist could call in the help of an endodontist to perform a root canal treatment to at least save the tooth itself. If the tooth has darkened in color, chances are that the nerve of the tooth is dying or has died, and a root canal could be performed in this case as well.

Endodontics is performed in order to prevent infection from turning into abscesses, which could result in tooth loss.

A root canal treatment is a procedure that is performed by a specialist dentist to carefully and completely remove all infection from the inside of the tooth (called the pulp). During treatment, the doctor will remove the diseased pulp from inside the tooth, carefully clean and shape the root canal spaces and then seal the prepared canals with special filling materials.
Inflammation or infection can be caused by deep decay in the tooth due to repeated dental procedures on the tooth, or a chip or crack in the tooth. A blow to a tooth may also cause pulp damage even if the tooth has no visible chips or cracks. If an inflamed or infected pulp is left untreated it can cause pain or lead to an abscess.
No! The procedure is intended to relieve pain or to prevent it! Your dentist will give you a local anesthetic and it will feel the same as when you have a normal filling done. Some people will feel a bit of tenderness afterwards, but it will go away soon.
Every person is unique and the causes for the infection may differ, but generally most root canal procedures can be completed in about an hour.