Root canal therapy or root canal treatment is also known as endodontic treatment or endodontics.
If your animal has an endodontically diseased tooth, it does not always need to be extracted. These teeth can usually be saved with root canal therapy if performed within a reasonable time. Your veterinarian can refer the animal to a veterinary dentist to assess whether the tooth is suitable for endodontics.
The Dental Pulp
The main function of the dental pulp is to keep the tooth alive and healthy. The nerves supply sensation to the tooth (and when irritated signal dental pain). The blood supply and tissues allow continued production of dentine (common name ivory) inside the tooth to strengthen the tooth internally as the enamel wears with age. This means that the root canal gets narrower with age (in the young animal it is a large, wide space whilst in the old animal it is almost obliterated).
The tooth itself does not stay in the mouth whether it is vital (= alive) or not. It stays as long as the supporting structures are healthy. The support structures for teeth are the gums, periodontal ligament and bone of the socket. Hence good, healthy teeth can be lost due to severe gum disease (periodontal disease) and non-vital teeth can remain if the support is healthy. Hence root canal therapy can allow the tooth to stay and function as normal.
How does the pulp become diseased?
Pulp death can also occur as a result of excessive wear of the teeth (such as dogs with flea allergy dermatitis), trauma to the teeth (which causes internal bleeding in the pulp chamber and a build-up of pressures and inflammation) and sometimes for no apparent reason at all (which means that the tooth will look OK externally).
Dog with a fractured canine tooth with pulp exposure
What is involved with root canal treatment?
During root canal treatment firstly an access is made into the tooth (this may be through the fractured area) to allow instruments to be used to remove all of the internal organic components of the pulp. The canals are then cleaned, disinfected and dried. Next, the root canal is filled with material that doesn’t allow bacterial infection to re-occur. Basically the canal is completely sealed. The final stage involves a restoration (filling) to seal the access and pulp exposure.
In some cases it may be recommended that the tooth also has a crown fitted to protect the remaining tooth structure although this is usually not required.
During root canal treatment a number of x-rays are taken. These are required to check the progress of treatment and finally to assess the effectiveness of the treatment.
X-ray of a tooth with a root canal file to assess “working length”
Final x-ray of a dog with root canal therapy of both lower canine teeth
How successful is root canal therapy?
We won’t attempt root canal therapy if we don’t think it has good chance of success. Of course, no guarantees can be given as the animal’s behaviour is beyond our control and, after all, it broke a perfectly healthy tooth in the first place.
Most root canal treatments will last for a long period of time but, to ensure all is progressing well, follow-up x-rays are essential to assess that there is no deterioration around the tooth root. Very occasionally a second procedure can be required to remove all of the infected material around the tooth root especially in cases that were long-standing before treatment.
Final appearance of a root canal treated canine tooth on a Polar Bear