Ask the dentist – what is a root canal?

When tooth pain drives you to seek dental treatment and your dentist mentions “root canal”, don’t panic. As GMHBA dentist Dr Anna Stokes explains, root canal treatment can be a highly effective and long-lasting solution.

Why would I need root canal treatment?

A tooth has essentially three layers:

  1. The outer shield of enamel, which is the shiny white part of the tooth you can see in your mouth
  2. This covers the softer dentine, which makes up the bulk of the tooth structure, including the roots
  3. Then in the middle is the pulp, which contains nerves, blood vessels and connective tissue.

The pulp is what gives the tooth “life and feeling”. It extends from the middle of the tooth through to the tips of the roots in canals, where is joins the surrounding tissues. Sometimes the pulp becomes irreversibly inflamed or dies and becomes infected. There are several causes of irreversible inflammation of the pulp, these include cracks, trauma, deep decay or a previously deep filling.

The symptoms of irreversible inflammation may be:

  • Pain and/or swelling
  • Hypersensitivity to temperature (often hot more than cold,) that lingers after the trigger has been removed
  • A dull constant ache or throb which can disturb sleep and may require painkillers
  • Tenderness in the tooth when biting
  • Swelling in the surrounding gum or the development of a “pimple” as infection develops

In order to treat this, the pulp is removed, the space disinfected and, once the symptoms and infection have settled, the tooth is filled. This is called endodontic or root canal treatment.

What is involved in root canal treatment?

root canal treatment usually takes around two to four visits before the final filling is placed in the tooth.

At each visit, local anaesthetic is used to numb the tooth and surrounding soft tissues in the same way your dentist would for a filling. A small square sheet of rubber, called a rubber or dental dam, is then placed over the tooth and held in place with a clamp. The purpose of this is to isolate the tooth from the saliva in your mouth so the tooth can be cleaned and kept clean during the procedure. It also reduces the chance of anything going into your mouth or throat while dentist is working on your tooth.

Any decay present is removed, and a small hole is cut into the tooth to locate the pulp. This feels similar to preparing a tooth for a filling. The pulp is removed with small files. These are then used to shape the root canals and remove any infected tooth structure. Disinfectant is used to irrigate the tooth during this procedure to help clear away the debris and so the canals are cleaned both physically and chemically.

Between each appointment an antimicrobial solution is placed in the pulp chamber and the tooth is filled with a temporary filling. After each appointment there can be some soreness when the numbness wears off, but this usually requires no more than over the counter painkillers like paracetamol or ibuprofen. Occasionally the discomfort can be more severe, or a swelling can develop in which case antibiotics may be required.

Your dentist will need to take x-rays at various stages to confirm all the canals have been located and cleaned completely. Once all the canals have been cleaned, any infection resolved, and all symptoms settled, the root canals are filled with a rubber-based substance called Gutta Percha and a sealer. The tooth is then filled.

Does a root treated tooth have to be crowned?

The process of root canal treatment basically hollows the tooth out which tends to weaken it and make it more prone to fracture. For premolars and molars, it is important that the tooth is restored with an adequately strong final restoration, which should cover the whole of the biting surface of the tooth. Sometimes, but not always, this is best achieved with either an inlay-onlay restoration (in either gold or porcelain) or with a crown.

Root treated teeth can also become darker over time. In some cases, this can be reversed with whitening treatments, but in other cases a crown may be recommended.

Will it work?

In most cases root canal treatment is successful for several years. However sometimes the case is more difficult. The tooth may be just too compromised, and it fails sooner. This can be due to recurrent decay, reinfection or fracture. When the tooth is assessed initially, and it is determined root canal treatment is indicated, your dentist will assess the tooth to see if root canal treatment is appropriate. Be aware your dentist can only try to predict the success rate, not promise it, as there’s too much natural variation and no-one can definitely say what will happen in the future.

What are the alternatives?

Sometimes root canal treatment is not recommended. Some examples of reasons include because the tooth has a crack that extends into the root, the infection may have caused the root to partially dissolve or “resorb”, the infection may have compromised the supporting bone too much, the tooth may be unopposed or non-functioning and not affect your appearance, the tooth maybe too badly damaged to be restored or your medical history may make it inadvisable.

If root canal treatment is not recommended or you decide not to proceed, extraction of the tooth is the only option. This can seem like an easy solution to the problem when you are in pain, but there are long term considerations to this decision. If a tooth is removed and not replaced, surrounding teeth can move, increasing your risk of further dental problems. While teeth can be replaced, in most cases your natural tooth generally functions better than an artificial one and replacement options are not without risk.

Options to replace a missing tooth include an implant, bridge or denture and your dentist will discuss these options with you and recommend which they feel is the most appropriate for you.

Are there any risks?

In most cases root canal treatment are successful and relatively painless. However, as with all dental procedures root canal treatment does have some risks and there can be complications:

  • Fracture of the tooth either during the procedure or after
  • Infection or cysts
  • Pain (generally this is minor)
  • Procedural errors like the position or angle of the tooth
  • Fracture of an endodontic file in the root canal

How can I prevent root canal treatment?

The best way to prevent the need for root canal treatment is to keep your mouth, teeth and gums healthy.

  1. Brush twice a day
  2. Floss once per day
  3. Visit your dentist regularly
  4. Look at the lifestyle factors

But sometimes, despite our best intentions, root canal treatment may become necessary.

Find out more

Talk to the team at GMHBA Dental Care for all your dental needs.