Feline tooth resorption

Symptoms an owner can spot at home

• Chewing on one side, dropping food, or reluctance to eat hard kibble
• Increased drooling
• 'Chattering' of the jaw when the affected tooth is touched
• Pawing at the mouth
• Weight loss in advanced cases

When to see a vet

• Any drooling, dropped food, or new preference for wet food in a previously kibble-eating cat
• Visible red gum tissue growing over a tooth, a hallmark sign of resorption
• Halitosis, especially with visible tartar or a chipped tooth
• Annual comprehensive oral exam under anesthesia with dental radiographs from age 3, this catches subclinical resorption

What it is

Tooth resorption (formerly 'feline odontoclastic resorptive lesions', FORLs) is destruction of dentin, cementum, and enamel by activated odontoclasts. The exact cause is unknown, hypotheses include chronic subclinical inflammation, dietary factors, and vitamin D metabolism, but none are definitive. Lesions are classified by location (Type 1: periodontal ligament preserved; Type 2: PDL replaced by bone; Type 3: mixed) and by radiographic stage.

Cats are exceptional at hiding oral pain; a cat with active resorption often eats normally and gives no obvious sign until the disease is advanced. Owners are frequently surprised by 'no symptoms' cats who become dramatically more affectionate and playful after extractions, a functional demonstration that the pain was real.

How vets diagnose it

Definitive diagnosis requires full-mouth dental radiographs under general anesthesia, roughly half of resorption lesions are undetectable on visual exam alone. Awake oral exams are useful for screening but cannot substitute for anesthetized comprehensive oral evaluation (COHAT). AVDC and AAHA dental guidelines recommend COHAT annually starting at age 1-3 for cats.

Treatment overview

This is editorial overview, not a treatment plan. The only effective treatment for symptomatic Type 1 lesions is complete extraction. Type 2 lesions, where the PDL is gone, are sometimes treated by crown amputation with intentional root retention, this is only appropriate when the root has no periodontal ligament visible on radiograph and no evidence of endodontic or periapical disease. Restoration (fillings) does not work because the resorption process continues.

What owners can do

• There is no proven prevention. Focus on early detection: annual COHAT with dental radiographs.
• Home tooth-brushing, VOHC-accepted dental treats, and dental diets support overall oral health but do not prevent resorption.
• Do not accept 'anesthesia-free' dental cleanings, they cannot diagnose or treat resorption and often miss significant disease.
• Report any change in eating behavior, dropped food, or preference for wet food to your vet, cats do not obviously advertise oral pain.