Cat Dental Disease: Stages, Signs and Treatment

Dental disease in cats is an infection of the tissues that hold the tooth. It starts as gingivitis and, left alone, can reach the ligament and the bone; a separate condition, tooth resorption, dissolves the tooth itself. The three are the most common dental diseases in cats, and the severity of each varies widely. The four rows below use the wording the veterinary sources give rather than an invented scale.

What periodontal disease actually is

Periodontal disease has exactly two forms, gingivitis and periodontitis, and the difference between them is the tissue list. Gingivitis sits in the gum. Periodontitis goes deeper and the damage reaches the gums, the ligaments and bone, which makes it a structural problem rather than a surface one.

That is why "just tartar" undersells it. Tartar is the visible deposit; periodontal disease is what the deposit and the plaque around it feed underneath. The AAHA's definition of a healthy-mouth prophylaxis points at the same thing from the other side: the cleaning removes plaque and calculus above and beneath the gum line, under anesthesia, before periodontitis develops. The below-the-gum half in that sentence is the half that decides the outcome.

The stages, with sources

The AVMA grades periodontal disease from 0, normal, to 4, severe. The table collapses the middle into the two named forms and adds resorption, which runs alongside rather than after them. Each row quotes the source, with the page and the date it was checked.

Resorption is the odd one. Cornell reports that it affects an estimated 20 to 60% of all cats and close to three-quarters of cats five and older, and it follows a different route from the plaque that drives periodontitis. Where it becomes painful, the tooth is usually extracted.

The signs

The AVMA's list is the reference and it runs wider than breath. Bad breath, broken or loose teeth, extra or retained baby teeth, discoloured teeth or tartar, abnormal chewing, drooling, dropping food, a reduced appetite or refusal to eat, pain around the mouth, bleeding and swelling.

• Breath that has changed.
• Blood on a chew, a toy or the gum after eating.
• Drooling, or dropping food, a change in how the cat eats.
• A reduced appetite, then refusal to eat.
• A tooth on the floor, or one that moves when touched.

Cornell names periodontal disease as by far the most common problem associated with bad breath, so the smell is not an incidental detail on this list; it is the entry point most owners notice first.

How calculus forms

Plaque builds again within days without brushing. Left there, it hardens into calculus, and the rough calculus holds a new layer of plaque against the gum. The cycle is self-feeding: the deposit makes the surface harder to clean, the harder surface holds more plaque, and the gum underneath stays inflamed.

A brush cannot break the cycle once it reaches the calculus stage. The AAHA is explicit that brushing removes plaque and not calculus, which is why the professional scaling exists and why brushing alone stops being enough.

Plaque versus calculus

Plaque is the soft film, and it comes off with a brush. Calculus is the same material once it has hardened, and a brush does not shift it. Plaque is the active problem; calculus is the platform that keeps the problem going.

The practical consequence is a split in who handles what. Plaque belongs to the owner and the brush, daily. Calculus belongs to the clinic and the scaler, at the interval the vet sets. An owner who brushes but never books in handles the plaque and leaves the calculus.

Gingivitis and its window

Gingivitis is the stage with a way back, and the window closes quietly. Merck says it can be reversed with proper tooth cleaning, and that untreated it may lead to periodontitis. It also says established gingivitis can usually be treated by a thorough professional cleaning under anesthesia.

The word "reversed" does not mean "will reverse on its own". It means the tissue can return to normal if the cause is removed, and the cause is the plaque along the gum that a brush cannot fully clear once the gum is inflamed and sore. That is the moment to book rather than to redouble the brushing.

Infection and abscess

Once bacteria are working at the root, the body walls the infection in and an abscess can form. It can look like a swelling on the jaw or under the eye, often with heat, and a cat that flinches from the side of the face. Cornell describes infection that in some cases spreads to other organs, and the deeper the pocket the more tissue is available for it.

An abscess at the tooth root needs prompt treatment: the swelling can burst, and a cat that stops eating from facial pain goes downhill fast. It is also preventable by treating the periodontitis before the root is involved.

What the vet does

The sequence is diagnostic before it is therapeutic. Examination of the awake mouth first, then x-rays of the head and jaw, which Cornell notes require anesthesia. The AVMA says radiographs may be needed to evaluate the jaw and the tooth roots below the gumline, and Merck says the extent of bone support loss is determined from x-rays of the jaw.

Then the work: scaling to remove plaque and tartar, polishing, and extraction where the x-ray and the probe show a tooth cannot be kept. Merck's note on the outcome is reassuring: extractions allow the tissue to heal, and dogs do surprisingly well without the teeth.

Why owners notice late

Cats can keep eating through a surprising amount of oral pain. Most dental disease also sits below the gumline where it cannot be seen, so the part an owner can inspect is the least informative part. The result is a disease that is usually advanced by the time it is visible as something other than a smell.

An owner is not failing by missing it; the cat is hiding it and the disease is under the surface. What closes the gap is a schedule rather than vigilance: an annual check, a look at the signs list now and then, and a lower threshold for booking.

The links to kidney, heart and diabetes

The AVMA lists kidney, liver and heart muscle changes among the health problems found in association with periodontal disease. Cornell's version of the same point is infection that in some cases can spread to other organs. Neither source claims the mouth causes those conditions, and that distinction is worth keeping: the association is what is documented.

What it changes is the framing. A mouth with a chronic bacterial load is not a local inconvenience, and an owner weighing whether to book is weighing more than fresh breath.

Questions owners ask

Where to go next

The necessity page weighs why the cleaning matters, the problems page compares a healthy mouth with a diseased one, and the procedure page walks the appointment.