Dental trauma is the most frequent precursor to endodontic disease, and is the most common indication for endodontic therapy in companion animals. Clinical signs of endodontic disease can be obvious or subtle, ranging from tooth sensitivity, flinching, drooling, vocalization, increased calculus at the affected tooth, change in temperament, decreased chewing on favorite toys, inattention, reduced sense of smell, or inexplicable circling to the affected side. In people, pulp inflammation is painful, yet dogs are unreliable about displaying obvious signs of pain. They have many characteristics handed down to them from their wild ancestors, including a disinclination to display obvious signs of discomfort.

Dogs are unreliable about displaying obvious signs of pain.

When the pulp is exposed after tooth fracture, it is only a matter of time before pathogenic bacteria descend into the pulp canal to cause an abscess either within the canal itself or periapically by extension of the infection. Infection that has escaped through the apical end of the root canal can cause osteitis, and surrounding bone can subsequently be lost. Periapical infection can spread, contributing to pathologic fractures of the lower jaw, or the infection can extend through weakened necrotic bone and develop into an oronasal fistula from any of the maxillary teeth.

It is only a matter of time before pathogenic bacteria invade.

For these reasons, it is recommended that endodontically compromised teeth receive exodontic (extractions) or endodontic therapy.

Why Not Simply Extract?
Endodontic therapy is much less invasive than surgical extraction of a large canine or carnassial tooth, and in many cases, quicker to perform. Compared to surgical extraction, standard root canal therapy is less traumatic and painful for the patient and more aesthetically pleasing to the owner. The cost of root canal therapy is similar to that of an appropriately charged surgical extraction. Another advantage of small animal endodontics is the relatively short life span of veterinary patient; a properly performed procedure is less likely to fail in the pet's lifetime. Success rates at Apex Dog and Cat Dentistry are about 95-100%, for the life of the pet!

What’s “Root Canal Treatment” Anyway?
Briefly, the essence of a standard root canal procedure is to make an appropriate access to the pulp through the crown, remove all the pulp in the tooth, and debride and shape the root canal to remove any overhangs. The root canal is then disinfected, dried, and obturated (filled) with a bio-compatible material (e.g. gutta-percha) and an antimicrobial root canal sealer is applied to seal the apex and the walls of the canal. Finally, the access site is filled with a quick-setting, hard restorative material. In some cases, metal crown placement may also be considered to provide additional protection.

Six Steps to Root Canal Therapy

1. Dental radiograph	2. Pain management
3. Pulp canal access	4. Instrumentation
5. Obturation (filling)	6. Composite restoration

1. Dental radiograph
   Intra-oral dental radiographs before, during, and after the procedure are essential.
2. Pain management
   A multimodal approach to pain control is utilized, including bupivicaine 0.5% nerve blocks.
3. Pulp canal access
   The pulp canal system is accessed and root canal “working lengths” are determined.
4. Instrumentation
   The canals are cleaned and shaped with hand or engine-driven rotary files.
5. Obturation (filling)
   After the canals are disinfected and dried, they are filled with a biocompatible radiopaque material.
6. Composite restoration
   Surface restoration is accomplished using a light curable composite. A metal prosthetic crown may also be considered.
   

When To Refer?
When faced with a patient displaying tooth fracture, don’t take a watch and see approach. Talk to pet owners about treatment options. Often extraction is appropriate and indicated; however, many pet owners would like the option of saving a tooth rather than having it extracted. Root canal therapy should then be considered.