Root canal

What is a root canal?

A root canal treatment involves cleaning out the space inside the tooth (canals) then shaping the canal space. This space is filled up to prevent bacteria from getting back into the root system and causing re-infection.

The purpose of a root treatment is to allow a dying or dead tooth, without a living nerve to remain functioning successfully in the mouth without pain and for obvious cosmetic reasons.

When a nerve dies in a tooth it is often referred to as 'non-vital'. Sometimes it may be painless for a time but it is still infected and when the balance of bacteria is upset an abscess (collection of pus) will form. This is why your dentist will recommend a root canal treatment to save the tooth. Root canal is carried out with local anaesthetic to aid comfort and a rubber dam is used to isolate the tooth allowing sterility to be maintained. Usually 1-3 visits are needed dependent on the amount of infection and complexity of the canals in the tooth.

The success of a root canal treatment at 10 years is reported to be:

  • 90-95% for an initial root canal. (I.e. the first time it has been attempted) if there is no area visible around the tip of the root on the X-ray.
  • 80-85% for an initial root canal if there is an area associated with the tip of the root on the X-ray.
  • 65% for a re-root treatment (i.e. following an unsuccessful first attempt)

The success of a root canal comes down largely to whether the whole root system of the tooth has been sufficiently disinfected, appropriately filled and properly sealed. If this is the case then the root canal is very likely to be successful.

Any factor that influences achieving this will affect the success of the root canal treatment. These could be:

  • The tooth itself and there are many issues related to the tooth that can influence the success.
  • How infected the canal (s) are initially. The more infected the root system, the poorer the success rate
  • How much tooth remains, although this may not actually affect the success of the root canal procedure directly, it will affect how strong the crown is on top and therefore how long you then have a useful tooth in your mouth
  • How complex the root canal system is, how curved, how many and how accessible the canals are, will all be factors that will influence the difficulty of the treatment and hence the outcome
  • If it is the first time a root canal treatment has been attempted or if it is a re-root canal treatment as statistically these are not as successful
  • It is a natural tooth that is being treated, or a crown. Access to canals through a crown can be more difficult as the natural anatomy has gone. Your dentist may advise replacement of the crown to allow successful root treatment and sealing to prevent crown leakage and re-infection
  • Seal of the tooth afterwards to ensure bacteria does not re-infect the root canal. If the tooth edge is below the gum or bone level this may not be achievable.

At Wimborne dental we perform root canal treatment everyday, but specialists (endodontists) have had several years additional training in this treatment, and limit their practice specifically to treat these teeth with specialised equipment (e.g. high magnification microscopes). As a result, the success rate for difficult root fillings with a specialist root canal treatment could be higher as would be the cost. We will advise you if specialist treatment will be more beneficial.

  • Maintain functioning tooth for appearance and chewing capacity
  • Can act as an anchor tooth for a denture or a bridge in more complex treatments
  • No bone shrinkage as the tooth needs bone support
  • Preserving tooth avoids adjacent and opposing teeth from moving
  • Requires multiple and long treatment times
  • Investment level is more
  • Higher risk of fracture, so the top of tooth needs protection which adds to the investment level
  • Less than 100% success rate so further treatment may be required immediately or in the future
  • Decay and gum disease can still affect the tooth but is avoidable with effective homecare

It is recommended that patients attend for at least six-monthly prevention and plaque control visits because it is important that good oral hygiene is maintained to keep the tooth clean and prevent plaque build-up. It is the patient's responsibility to look after the tooth at home and maintain good oral hygiene procedures.