Root Canal Treatment

What is it?

A root canal treatment is a procedure in which the pulp (consisting of nerves and blood vessels) is removed from the tooth, and the empty root canals cleaned, allowing them to be filled back up with a rubber material.

Why is it needed?

Patients will need a root canal treatment when the pulp has become irreversibly inflamed, infected, or has died. This may be caused by deep decay, a fracture, or severe periodontal disease. When infection spreads through the pulp, it’ll eventually travel out the end of the root (which is called the apex), and infect the surrounding area causing a dental abscess. This can become incredibly painful for the patient, and is the most common cause of toothache causing issues such as:

• Swollen gum tissue

• Pain when biting and chewing

• Sensitivity to hot and cold food and drinks

In order to save the tooth, the infected tissues inside the tooth need to be removed, and the area completely cleaned of any residual bacteria. By filling the roots back up again, the infection is stopped in its path, and will eventually clear up, ending the pain.

The steps involved:

1. Local anaesthetic

The tooth is usually numbed using a couple of injections. Not only does this stop the pain of the toothache, but it also prevents you feeling anything during the procedure, making it relatively painless.

2. Rubber dam

After numbing the tooth, a rubber sheet called a rubber dam is put on the teeth to isolate the tooth in question. A clamp is attached to the tooth to hold the sheet of rubber in place. The purpose of this is to keep the tooth sterile, and to protect the mouth from the chemicals used in the cleaning process whilst also providing protection for the patient’s airway.

3. Accessing the pulp

The tooth is then accessed. This involves drilling into the biting surface of the tooth to “access” the pulp chamber below.

4. Shaping and cleaning the root canals

Once the tooth is opened up, and all the roots are visible, the next step is shaping and cleaning. Tiny hand files and modern flexible rotary files are used to clear out all the diseased and dead material inside the roots, and open them up so that the filling material can later be placed inside. We only use our files once, in order to minimise the risk of fracture and reduce the risk of cross infection. Powerful disinfectants are used to kill any residual bacteria. The root canal lengths are accurately measured using a combination of x-rays and a machine called an apex locator.

5. Filling the root canals

Once the canals are cleared, they can be filled using gutta percha. This is a rubber material, that comes in thin pellets. These are packed into the root with a glue until the canal is at maximum capacity, ensuring there are no gaps. Once filled, the top is cut off and the rubber is packed down, condensing the material even further. Our visiting dentist with special interest in endodontics is able to complete this stage using advanced warming techniques such as ‘Obtura’ and ‘System B’ to soften the rubber material in order to pack it extremely tightly into difficult to restore fine roots thereby decreasing the risk of re-infection.

6. Restoring the tooth

The cavity in the crown is then filled with a standard filling material. A variety of options will be considered for the final restoration. There are high risks of fractures with the posterior teeth (molars and premolars) due to the increase in fragility after root canal treatment and the forces applied to them when biting. The dentist will frequently recommend that a crown or an onlay (less extensive than a crown but still covers the cusps of the tooth) should be placed. Dental crowns and onlays provide a strengthening effect that can help to prevent fracture.

If there is excessive tooth breakdown, a post may be placed in the root with a core which will support a crown. You may experience some post-operative pain once the local anaesthetic wears off. This is common, as there has been disruption to the nerves inside your mouth. This usually settles down with pain killers, and shouldn’t last long. Root canal treatment is commonly perceived as being a painful procedure but with modern endodontic techniques it is relatively painless, and should be no more unpleasant than having a filling placed.

Root canal treatment is one of the most challenging treatments for a dentist to perform and may take several appointments to complete successfully. In more complex cases or tricky re-root canal treatments your dentist may recommend a referral to a specialist endodontist.