Feline tooth resorption, or feline odontoclastic resorptive lesions (FORLs), are common in cats with up to 75% of cats being affected. This condition is most commonly seen in cats over 5 years old, but cats of any age can be affected. The cause of feline tooth resorption is unknown.
Feline Tooth Resorption
Cat teeth have a central pulp canal that contains blood vessels, nerves, and lymphatic vessels. If the pulp canal becomes infected or damaged, it can cause pain and lead to the death of the tooth. Surrounding the pulp canal is a layer of dentin. Dentin is a bony substance that makes up the bulk of the tooth. The crown of the tooth is the portion of the tooth above the gumline. The crown has an outer hard layer called enamel. Enamel is one of the hardest substances in the body and protects the softer dentin from damage. Below the gumline is the root of the tooth which is surrounded by cementum. Cementum is similar to enamel in that it protects the softer dentin underneath.
Feline tooth resorption often starts in the cementum of the tooth near the gumline and develops inwards into the dentin layer. The resorption can then spread downward into the root of the tooth, upward into the crown of the tooth, or in both directions. As the dentin erodes away, the structure of the tooth becomes compromised leading to pain and eventual tooth fractures.
Cats are often very stoic and hide their pain and discomfort well. Some signs you may notice that indicate your cat is suffering from tooth pain include drooling, turning their head sideways to chew on one side of the mouth, eating dry food without chewing, dropping food while eating, or suddenly preferring canned food over dry food. In many cases, these signs are not noticed and resorptive lesions are identified during a routine dental cleaning.
The only treatment for teeth affected by resorptive lesions is to extract them. Oral radiographs (x-rays) are recommended for the other teeth even if they appear normal because lesions can be present only below the gumline. Even these teeth should be extracted because they can be sources of pain for your cat and will only worsen.
Sometimes tooth resorption can be accompanied with a condition called stomatitis, or inflammation of the tissues in the mouth. In this condition, the back and sides of the mouth can be swollen, red, and sometimes bloody. Cats with this condition often have a decreased appetite, foul smelling breath, and profuse drooling.
Cats with stomatitis often require most if not all of their teeth extracted to resolve the disease. Even if the teeth appear normal, they require extraction due to the severe nature of this condition. In addition, these cats require strong pain medications and antibiotics to encourage them to eat.
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