Feline Tooth Resorption Syndrome


It's a mouthful, for sure: "Feline tooth resorption syndrome" (TR) is a disease characterized by the destruction of dental material by cells called odontoclasts. This condition in cats goes by plenty of other names, too: Feline odontoclastic resorption lesion (FORL), neck lesion, cervical neck lesion, cervical line erosion, feline caries, or feline cavity are just a few of its alternative names.

TR is counted among the most common dental conditions in domestic cats. Affecting up to two-thirds of all cats, these painful dental lesions are somewhat akin to cavities. But unlike cavities in humans, which are caused by sugar-eating bacteria that produce a tooth-destroying acid, their underlying origin is either inflammatory in nature or idiopathic, both of which suggest that the cause of this syndrome is effectively unknown.

Symptoms and Identification

The clinical signs of TR are unmistakable once owners know what to look for: A pinkish defect in one or more teeth will be noted at the gumline of the diseased tooth (or teeth).

The lower (mandibular) third premolar is the most commonly affected tooth.

Unfortunately, however, most owners are unable to properly assess their cats' teeth due to their unfamiliarity with cats' mouths. Moreover, these lesions are sometimes obscured by tartar, which makes identification difficult. That's why most owners must rely on circumstantial evidence of pain before they'll suspect that something is amiss.

Though most cats will display no outward signs of pain, the following signs are often associated with oral discomfort in cats:

  • Messier than usual eating style (food falls outside of bowl)

  • Tilting the head when eating (as if trying to chew on one side of the mouth)

  • Regurgitating food (unchewed kibble comes up soon after eating)

Diagnosis of TR is generally achieved via simple observation during a physical examination or routine dental cleaning. However, dental X-rays are required to observe the integrity of the tooth's root. The correct approach to treatment relies on this bit of diagnostic imaging.

Affected Breeds

All breeds of cats are susceptible to TR, but there's evidence that some purebred cats, especially Siamese and Persians, may be genetically predisposed. The means of inheritance is unknown.


Unfortunately, treatment of TR relies on the complete removal of the tooth. In cases where the root has been reabsorbed, a crown reduction (eliminating the visible part of the tooth) may be the only required action. If the root is present, however, a complete extraction is deemed necessary.

Complete anesthesia and pain relieving medications (local anesthesia and/or systemic pain relievers, such as opiates and NSAIDs) are required for this procedure.

Veterinary Cost

The cost of TR varies depending on the affected tooth and the degree to which the root is affected. For example, canine teeth (the "fangs") are considered more difficult to extract than premolars, molars and incisors are therefore more expensive to remove.

If extraction is required, as is often the case, expenses may top $300 to $500 per tooth, in addition to anesthesia (typically between $150 and $300), X-rays ($50 to $150), and pain relieving medication ($20 to $100). If the root is already reabsorbed, however, and the less-complicated crown reduction is possible, the cost will be significantly lower (about half of the extraction fee, in addition to the anesthesia, X-rays, and pain medications).

Owners should note that board-certified veterinary dentists tend to charge more for these procedures; often two to three times as much, due to their advanced degree of expertise.


Prevention of TR is not considered feasible. Early detection, however, is critical in terms of preventing pain. Owners who brush their cats' teeth are more likely to identify these lesions early on so they can be dealt with as soon as possible.


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