Tooth Resorption (TRs)
While pet tooth resorption is typically thought of as a feline condition, we see it more commonly in our canine patients. This problem is very common in cats, with studies suggesting that up to 60% of cats over 6 years of age are affected.
As of yet, we do not know exactly what causes pet tooth resorption. We know that resorbed teeth result from the activation of cells called odontoclasts. These cells are responsible for the normal remodeling of tooth structure. In this disease process, the odontoclasts inappropriately continue to resorb tooth structure until, in some instances, the entire tooth is lost.
Lesions May Develop
Tooth resorption lesions start on the roots, where the cells start destroying the underlying root structure. Over time, it extends into the crown of the tooth, exposing the underlying tooth structure, which is called dentin. This is very sensitive, causing significant pain. However, most cats will not show evidence of oral pain.
Because tooth resorption starts below the gumline and progresses into the crown of the tooth, they are first seen at the gumline. The teeth most affected are the premolars, followed by the molars, and finally the canine (fang) teeth.
Resorptive lesions are initially seen as little erosions with associated gum inflammation along the gumline. These lesions can progress to large holes in the teeth, eventually destroying most of the tooth. In severe cases, the entire crown of the tooth can be lost, with only the roots remaining under the gumline.
Veterinary dental x-rays are critical for treating patients with tooth resorption.
- First, x-rays are necessary to diagnose (find) lesions under the gumline.
- Secondly, x-rays are also required to determine the proper method of therapy.
The ideal therapy for TRs is extraction. In general, complete extraction of the tooth and all root structure is recommended. However, the resorption and ankylosis can make extraction quite challenging.
Therefore many veterinarians refer their feline pets to VDS for extractions.
In advanced cases, the roots can be completely replaced by bone. In this situation, a procedure called “crown amputation” has been developed. This is where the crown of the tooth is removed, the area smoothed, and sutured closed, allowing the body to continue resorbing the roots. This is a much less invasive procedure than a surgical extraction.
However, crown amputation can only be performed with advanced resorptive lesions if no root structure remains. Dental x-rays are required to determine this. Always insist on dental x-rays when taking your pet to the veterinarian for a dental procedure.