Feline Resorptive Lesions
Did you get tired of being bombarded with reasons why you should take care of your pet’s teeth during Pet Dental Health Month in February? Sorry, but I’m going to give you another: feline resorptive lesions, also known as FORLs.
A FORL is like a cavity on steroids. It starts out as a small hole in the enamel but can get so large that it essentially destroys the entire tooth. I can’t imagine how much this must hurt. FORLS typically develop around the base (neck) of teeth, which is why they are sometimes called neck lesions. The premolars and molars at the back of the mouth are most commonly affected.
All types and ages of cats can develop FORLs, but risk increases as cats age and for some breeds like Persians, Siamese and Abyssinians. Dogs can also get resorptive lesions, but the condition is less common in this species.
Left untreated, resorptive lesions progress through five separate stages:
- Stage 1 — During this earliest stage the lesions only affect the tooth enamel and often go unnoticed because they have not begun to cause the cat pain.
- Stage 2 — Cats experience some discomfort with stage 2 lesions involving both enamel and dentin, but it is usually mild enough that a cat’s behavior may not be noticeably affected.
- Stage 3 — In stage 3, the tooth’s pulp cavity is exposed and pain is intense. However, some cats will do all they can to mask their pain, so the symptoms that owners do notice (see below) may not be all that dramatic.
- Stage 4 — During this stage, most of the tooth has been destroyed by the resorptive lesion.
- Stage 5 — Finally, the gums grow over the small amount of dental tissue that remains.
Oral pain is the best indicator that your cat might be suffering from one or more FORLs. Cats may not want to be touched near the mouth. Affected individuals are often reluctant to chew, especially if they are eating dry food. Kibble may drop from the mouth and be found scattered around the food bowl. Excessive drooling, sometimes blood-tinged, is also common. One of the classic signs of tooth pain in both dogs and cats is teeth chattering. Owners often notice this behavior (typically after a cat eats, drinks, or is touched in or around the mouth) but don’t typically associate it with pain.
Your veterinarian can diagnose resorptive lesions with an oral exam, but sedation is usually necessary for the whole mouth to be examined. For this reason, many veterinarians will simply schedule a dental cleaning (assuming one is needed) with its attendant anesthesia, and perform the complete oral exam at that time.
If a FORL is found, the affected tooth has to be removed; this is currently the only method of treatment. Over the years, many other treatment options have been tried (drilling, filling, etc.), but they have all failed. In some cases, your veterinarian may be able to perform a crown amputation — cutting off the visible part of the tooth while leaving the roots behind — on the tooth, while other teeth may require a complete extraction. Dental X-rays are necessary to determine the best way to proceed.
Once the tooth is gone, the pain is gone. Trust me, your cat won’t miss the teeth. He or she will be much happier without them and the pain they were causing.
Dr. Jennifer Coates