Endodontics
The dental pulp, or the endodontic system, is the inner living component of teeth that contains their blood and nerve supply. The pulp system is responsible for tooth nourishment and produces tooth sensation. When injured or exposed, it results in tooth pain. Injury or exposure of the pulp system can result in a number of ways including systemic infection, crown fractures, advanced cavities or caries, tooth resorption, or by inadvertently over-rasping during dental float procedures.
Pulp injury results in pulp inflammation, or what veterinary dentists call pulpitis. Pulpitis leads to pulp disease that spreads through the pulp system and ultimately can cause tooth death. Pulpitis can be reversible. An injured tooth can occasionally repair itself by depositing a bridge, sometimes called a stone, between the injured and underlying healthy pulp to wall off the insult, prevent the spread of infection, and save the tooth. This is nature’s own endodontic procedure. If no stone is formed, pulpitis may trigger tooth root infection and will lead to tooth death.
Performing endodontic procedures in horses is difficult due to their complex, variable and dynamic tooth structure. Horses have long-crowned teeth, meaning they have long and extensive pulp systems. Cheek teeth have 5-7 individual pulp horns running through their crown. These pulp horns don’t always communicate in a predictable pattern, making it extremely challenging to adequately sterilize the pulp system during endodontic procedures of cheek teeth. Incisor and canine teeth have simpler pulp systems and while still challenging, endodontic procedures of these teeth are more straight-forward. There are three basic endodontic techniques available for horses:
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direct application of a sealant over the exposed living pulp; typically not applicable.
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Full removal of the diseased pulp and partial removal of healthy pulp followed by a 3-layer restoration; recommended when the pulp insult is identified in a timely manner and there is still living, vital, pulp.
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Complete removal of the all of the pulp, disinfection, sealant of the canal, and a 3-layer restoration; recommended when the pulp insult is chronic and there is no longer any living, vital, pulp.
Case selection is extremely important to provide the best opportunity for long-term success. Endodontic procedures require continued monitoring and it is important to understand that failure of an endodontic procedure likely warrants tooth extraction.
After an endodontic procedure is completed, twice yearly oral and radiographic examination is recommended for two to three years. In some cases, a follow-up endodontic procedure is needed years later as a result of normal eruption and wear of the tooth with age. When performed in cheek teeth, a temporary endodontic therapy is performed followed by a permanent restoration four to six weeks later.
