What is endodontics?

Your tooth 

A tooth consists of two main parts:- the visible portion above gum level, known as the crown and the portion below gum level surrounded by bone comprising the root or roots

Each root has an internal channel running along its length called the root canal.The root canal contains nerves, blood vessels and other tissues collectively called the pulp but often known as the "nerve". The pulp is involved during the formation and development of the tooth. However, once matured, the tooth can survive without the pulp as it continues to receive nourishment from the surrounding tissues.

Cross section of molar tooth

When is endodontic (root canal) treatment necessary?

Endodontic treatment treats the inside of the tooth and becomes necessary following irreversible damage to the pulp. This can occur due to infection entering the tooth via decay, cracks, fractures and broken fillings. Infection may also gain access as a result of periodontal ("gum") disease or trauma. If this is left untreated, an abscess can develop.

Symptoms and signs to look for include spontaneous pain, prolonged sensitivity to hot or cold, tenderness to touch and chewing, and tooth discolouration. Sometimes the nearby gum tissues may be swollen and tender. Occasionally, there are no symptoms.

Endodontic procedure

The endodontist removes the inflamed or infected pulp and carefully cleans and shapes the root canal. The space inside the canal is then filled and sealed. Following this, you will return to your general dentist for a crown or permanent filling to protect the tooth and to restore it to full function.

The treatment is carried out in comfort and without pain under local anaesthetic while you are awake. You are always in control and should there be any discomfort at any time, the cause would be immediately dealt with before continuing treatment.

Rubber damWhen the tooth is numb, it is then "isolated" with a small sheet of rubber called rubber dam which is held in place by a small clip. Your tooth will then appear as if it is popping up through the centre of a trampoline!

This barrier stops water, debris, filling materials and disinfectants getting to the back of your mouth and throat. You can breathe, swallow and move your tongue normally throughout the whole procedure!

Under an operating microscope, an opening is then made through the top of the tooth to find the root canals and any decay is also removed at this stage. When found, to remove the inflamed or infected pulp tissue within, the canals are carefully cleaned and shaped with very small instruments and disinfectant fluids.

When the root canals have been cleaned and shaped, the space is then filled with a biocompatible material called gutta percha (a type of rubber) and a cement to ensure complete sealing. A temporary filling is then placed to seal the opening. This temporary filling will be removed by your dentist when the tooth is restored.


After your final visit, you will have to return to your dentist to have a crown or other permanent restoration placed to protect the tooth and restore it to full function.

Sometimes, there may be insufficient tooth structure remaining to hold the restoration in place, and a post may be needed. Your dentist or I myself can place a post into your tooth if required.

Endodontic retreatment (re-root canal treatment)

Occasionaly, a tooth may not heal following initial treatment. This can be due to various reasons:-

  • Narrow, curved or blocked canals were not treated during the orgininal treatment.
  • Complicated root canal anatomy was not recognised during the original evaluation.
  • A crown or a permananent filling was not placed soon enough following completion of the initial endodontic treatment allowing the canals to become reinfected. 
  • The crown or filling was leaking and failed to prevent reinfection of the root canals from saliva.

Sometimes, a new problem may affect a successfully treated tooth:-

  • New decay can cause reinfection of the root canals.
  • A loose, cracked or fractured filling or crown can can allow the canals to become reinfected.
  • The tooth may have fractured.  

Following evaluation and discussion of your treatment options, endodontic retreatment may be the treatment of choice. This involves reopening the tooth to gain access to the root canal filling material. Sometimes, restorative materials such as crowns have to be accessed or removed and posts removed if present so that the old root filling can be removed and the canals cleaned. Any missed canals or unusal anatomy found under magnification will also be treated. Following cleaning and shaping, the canals are filled and a temporary filling is placed to seal the opening.



After your retreatment is completed, you will have to return to your dentist to have a new crown or other permanent restoration placed to protect the tooth and restore it to full function.

If endodontic retreatment is not an option, the other options are extraction of your tooth or possibly endodontic surgery (apicectomy).

Endodontic surgery

Although there are several surgical procedures that can be performed to save a tooth, the most common one carried out is called apicectomy. This procedure may be able to save a tooth where nonsurgical endodontic treatment is not possible or recommended.

In this procedure, the endodontist opens up the gum tissue to see the underlying bone and to remove any inflamed or infected tissue. The tip of the root is also removed.


 A small filling is then placed in the root to seal the end of the root canal and a few stitches placed in the gum to help the tissues heal properly. Over the comming months, the bone usually heals around the end of the root.


Unfortunately, where there is persisitng inflammation or infection in the bony area around your tooth, the only alternative to apicectomy is extraction.