Feline tooth resorption. What is it and does it hurt?

Tooth resorption is a process by which the dentin (a hard tissue that lies beneath the enamel of the tooth) erodes and eventually becomes irreversibly destroyed. This erosion is extremely painful for your cat. Over time, all areas of an affected tooth may become involved. In the past, tooth resorption was referred to as feline oral resorptive lesions (FORLs), feline odontoclastic resorptions, cavities, caries, cervical neck lesions, external or internal root resorptions, and cervical line erosions.

The most affected teeth are the premolars of the lower jaws (specifically the third premolars). In one study, 53% of cats had an obvious tooth resorption lesion and where no obvious lesion was noted clinically, X-rays (radiographs) revealed one almost 50% of the time. This highlights how widespread and often hidden this painful condition is in the feline population.

What causes tooth resorption?

The exact cause of tooth resorption is unknown. Diet is believed to play a role. Other factors theorised to predispose a cat to resorption include frequent vomiting, periodontal disease, and mineral excesses or deficiencies in food or water. Tooth resorption in cats refers to a specific and significantly painful condition. Imagine having a cavity that constantly aches and exposes the sensitive inner parts of your tooth—that is what your cat experiences.

How do I know if my cat has tooth resorption?

If your cat has tooth resorption, she may show increased salivation, oral bleeding, or difficulty eating. Because this condition is so painful, some cats may only chew on one side of their mouth, drop food, or suddenly hiss or pull away when eating. You might notice them favoring soft food or refusing to eat dry kibble altogether.

Crucially, in many cases, cats are masters at hiding pain. Without radiographic and clinical screening in an anesthetized cat, tooth resorption will go undetected, and the cat will be in constant, silent pain. This is why annual, thorough veterinary examinations, including full-mouth dental X-rays, are absolutely essential for the maintenance of oral health and the early detection of this painful disease. Early detection is key to alleviating your cat’s discomfort.