Cat Teeth Problems: How to Tell Healthy Teeth From Unhealthy

A healthy cat mouth has a gum line that sits tight to the tooth and a clean crown. The drift away from that runs in order: a soft film first, then inflammation along the gum, then a hard rim of calculus, then a gum line that has begun to recede. The comparison below puts the two states in the same row so the difference can be read rather than guessed.

Healthy versus unhealthy, side by side

Each row is one feature, the healthy state and the state that means something has changed, with the source beside it. The normal end of the scale is where the AVMA's grading starts, at 0.

What healthy teeth and gums look like

The healthy mouth is the AVMA's grade 0, which it labels normal. In appearance the gum sits firm against the tooth, the crowns are clean or carry only soft film, and there is no smell beyond the ordinary. The back teeth at the gum margin are the place to look, because they are where the deposit gathers first.

Cornell frames the maintenance from the other end: regular removal of plaque by brushing is the best prevention of gingivitis. The healthy state is not a fixed possession; it is what the plaque removal keeps producing, day by day.

What changes first

The first drift is a soft film along the gum line of the back teeth, usually on the outside where the cheek meets the tooth. Then the gum margin reddens. Then the gum begins to pull back from the crown as the inflammation works.

• A faint brown or yellow line at the gum, which wipes off at first.
• Redness at the margin, worse on one side if the cat favours it.
• A gum line sitting visibly lower on a tooth than on its neighbour.
• Breath with a sour note that a meal does not clear.

Merck's key point about this stage is that it is reversible, and that untreated it may lead to periodontitis, where the tissue damage spreads to the ligaments and bone.

Plaque and calculus

Plaque is the film, soft and pale, and it comes away with a brush. Calculus is the same material once it has hardened, and a brush passes over it. The AAHA says brushing removes plaque and not calculus, which is why the two need different hands: plaque to the owner, calculus to the clinic.

The distinction matters for what the owner sees. A cat with a hard rim and no visible plaque still has a problem, and one with a soft film and no rim has an early one. Neither is a reason to keep brushing harder.

Loose and falling teeth

A tooth that moves or falls has one of three routes behind it. Periodontitis is the first: damage to the gums, ligaments and bone that hold the tooth, so the support erodes. Resorption is the second, and Cornell calls it the most common cause of tooth loss in cats, affecting an estimated 20 to 60% of all cats and close to three-quarters of those five and older. Trauma is the third, from a fall or a fight, as Merck names on its dog page.

A found tooth is not a small event. It is evidence that one of those routes has reached its end, and the mouth around it needs looking at.

The canines

The long teeth at the front are the ones a fracture shows on. A chip at the tip with a dark centre, a worn flat edge, or a colour change toward grey are the visible changes worth reporting rather than watching.

A broken canine that has exposed the pulp is painful in a way a cat will not announce, and it may abscess. The AVMA lists broken and discoloured teeth among the signs that need a check, and a tooth that cannot be repaired usually ends in extraction, which Merck notes allows the tissue to heal.

Signs of pain that are easy to miss

Cats eat through pain and hide the rest. The tells are behavioural rather than vocal, and they are mostly observation rather than a named sign: chewing on one side, dropping food, taking small bites, eating more slowly, and a general dullness that reads as age. A cat that approaches the bowl and then walks away is a cat to watch.

• Chewing on one side, or tilting the head to eat.
• Dropping food or holding it in the mouth before swallowing.
• A reduced appetite that has no other explanation.
• Flinching when the side of the face is touched.
• Less play and more sleep, which is the vague end of the list.

Most dental disease sits below the gumline where it cannot be seen, so these signs are often the only thing on the surface of a deep problem.

What you can check at home — and what you cannot

At home the owner can see the crowns and the front of the gum: the deposit, the redness, the breaks and the gaps. That is a real check and worth doing often. What the owner cannot see is the socket, the root and the bone.

The x-ray and the probe reach those, and Cornell notes that x-rays of the head and jaw require anesthesia. So a home check that comes back clean still proves only that the visible part is clean.

Normal or vet

The rule is the signs list rather than appetite. A clean mouth with no smell and no change is normal. Any of the following is a booking: bad breath that persists, bleeding gums, a loose or discoloured tooth, drooling, a change in chewing, a swelling, or a reduced appetite.

Cornell's line on the downside is pain, tooth loss and infection that can spread to other organs, which is enough to make the threshold for a call low. Two of these at once is not a wait-and-see.

The order of steps

Home check, then booking, then diagnostics, then treatment. The AVMA asks for teeth and gums to be checked at least once a year even when nothing looks wrong, so the annual visit is the fallback when the home check is clean.

Waiting for it to pass rarely works, because the disease has no stage that resolves without something removing the cause. Gingivitis needs cleaning to reverse, and periodontitis needs cleaning and often extraction on top. The disease page sets out the stages behind that order.

Questions owners ask

Where to go next

The disease page explains the stages and treatment, the dental health page covers prevention, and the cost page prices the appointment.