TOOTH RESORPTION IN CATS
One of the most common and most painful afflictions in cats is a condition referred to as resorptive
lesions (RLs). They appear as holes arising at or below the gum-line of the teeth. RLs cause a
progressive destruction of the tooth structure until complete root destruction or tooth fracture. RLS are
graded based on the severity and progression of the lesions.
An inflamed tissue covers the
affected region of the tooth.
Figure 1: Typical appearance of a
tooth resorption on a cat’s tooth
(lower left jaw). CVV inc.
Figure 4: Severe tooth resorption on
cat’s tooth (lower right jaw). CVV inc.
Figure 2: Same tooth after
removal of the inflamed tissue.
Note the 2 cavities (arrows). CVV
inc.
Figure 3: Radiographic view of the
same tooth: part of the crown and right
root are completely resorbed. CVV inc.
Figure 2: Radiographic view of the same tooth. One root is
almost completely resorbed. CVV inc.
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What is the cause of RLs?
Unlike cavities in humans, which are the result of bacterial enzymes and acids digesting the teeth, RLs
are the result of the cat's own body resorbing the teeth. The cause of RLs has not been determined at
this present moment.
Is my cat at risk?
Studies have shown that 20 to 75% of cats demonstrate tooth resorptions. They usually appear between
the age of 4 and 6 years old. The older the cat, the more likely he is at risk of developing RLs.
What can be done?
Early detection through an annual exam is the key. The oral exam may allow the veterinarian to notice
one or more resorptive lesions. Then careful dental examination with the patient anesthetized is
essential. Dental X-rays are also critical for evaluating the presence of other resorptive lesions and
the extent of the lesions, as well to establish the best treatment.
And the treatment?
When a lesion is detected, the recommended treatment consists of removing the affected tooth to stop
the resorption progression. In specific cases where the tooth root is ankylosed in the jaw bone, crown
amputation can be done followed by suture of the gingiva over the root.
How can we prevent tooth resorptions?
As we do not yet fully understand the causes of this feline peculiarity, we cannot make
recommendations for its prevention. For now, all we know for certain is that a cat that has had one or
more RLs will likely have more in the future therefore annual radiographic examinations are
recommended to find and manage new lesions.
Tooth resorptions are painful!
Dental pain: Although certain cats with resorptive lesions may show sign of pain (refuse dry food,
drop the food on the floor, decrease appetite), most cats adopt a stoic attitude and carry on despite the
pain. From an evolutionary standpoint, this is not surprising. Cats in the wild that display to the world
that they are ill or distressed are likely to quickly become prey for larger animal. Also, if they allowed
dental pain to put them off food, they would soon become too weak to hunt and would starve. On the
other hand, the improvement in attitude and demeanor after restoration or extraction of painful teeth
can be dramatic.
Reference:

Hale, Fraser. DMV, FAVD, DipAVDC, 2011. Tooth resorption in cats. Dental and oral surgery in pets.

D’astou, Jérôme. DMV, IPSAV. DipAVDC. 2014. Les résorptions dentaires chez les chats. Centre Vétérinaire DMV.
If you have questions, do not hesitate to contact us!
Clinique vétérinaire Vaudreuil Inc. 450-218-9090
By C. Senay February 2015
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