What is Root Canal Treatment (RCT)?
Root canal treatment involves removing the nerve and blood vessels (known as the pulp) inside the tooth. This treatment is necessary to save the tooth when the pulp is infected and dead because of decay or trauma from an accident or fall.
You may not feel any pain in the early stages of the infection. In some cases, your tooth could darken in color which may mean that the nerve of the tooth has died or is dying.
Some indications of the need for root canal treatment include:
- spontaneous pain or throbbing while biting
- sensitivity to hot and cold foods not relieved by other means
- severe decay or an injury that creates an abscess (infection) in the bone
What is done during root canal treatment (RCT)?
Root canal treatment may require 2 or more visits to the dentist as it has to be performed meticulously.
The aim of the treatment is to remove as much infection from the root canal. Some X-rays will have to be taken during the procedures. The tooth is isolated with a rubber dam and a clamp on the tooth.
During the first visit, the dentist will administer an injection (local anaesthetic) to area around the tooth. You will feel a bit “fat” at the cheeks when you are numb. The dentist will drill and remove all decay present and make an opening into the pulp chamber. Next, using a very fine instrument known as a file, the infected nerve is located and removed. The canal is rinsed and medication is placed inside the root canal to kill bacteria. A temporary filling is placed.
During the next visit, local anaesthetic will be administered again to numb the tooth. The temporary filling is removed. Progressively thicker files are used to clean and shape the entire length of the root canal. Medication is placed within the root again and a temporary filling is placed.
Depending on the number of canals and complexity of the case, this procedure may be repeated again on another visit.
Finally, the root canal is rinsed, dried and filled with a rubber material within the root. A filling is placed on top.
Why do we need to do crowns after RCT?
After root canal treatment, the tooth is non-vital/dead, so it becomes weak and brittle. It is weak because decayed areas and the centre of the tooth will have been removed in order to remove the infected nerve, leaving little tooth structure left for support. It is more brittle because the nerves and blood supply are gone. For posterior teeth that experience more forces during the chewing cycle, they may develop cracks & fracture if not protected with a crown.
If a tooth is very broken down, an additional core and post within the canal may be required.