a brown and white cat with its mouth wide open and its teeth showing

Help! My cat has bad breath

Have you noticed that your cat is suffering from bad breath (halitosis) or dental problems? Dental disease is often picked up at their annual health check by your vet. Dental problems are easy to spot and easy to prevent. In this article we will look at the causes and signs of dental disease, how you can help your cat and when to seek vet advice.

This article was written by a FirstVet vet


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Causes of bad breath in cats

In a healthy mouth, the gums should be uniformly pale pink and moist, and the teeth should be shiny and white (the crown), including the molars at the very back of the mouth! Bad breath isn’t normal and can be caused by many different things. For example, dental disease, diet, objects stuck in the mouth, kidney or liver disease, diabetes, airway infections or full anal glands. In rare cases bad breath can be a sign of an oral mass or tumour, so regular check ups with your vet particularly where bad breath is present are very important.

When plaque (soft white/cream coloured deposit) builds up it becomes calculus, also known as tartar. Tartar is a hard, brown material that sticks to the teeth, allowing bacteria to lodge on the surface. Plaque and calculus cause inflammation of the gum, which is called gingivitis. This usually affects the area of gum closest to the tooth. Gingivitis is identifiable as red, swollen or bleeding gums.

If an inflamed gum is not treated, it allows bacteria in the plaque to penetrate the tooth below the gum line. The bond between the tooth and the gum weakens, forming pockets of bacteria, which cause further tooth damage. At this stage, gingivitis is usually painful but can still be reversed with prompt treatment to remove the plaque and calculus.

Inflammation of the supporting structures of the tooth is called periodontitis. Left untreated, periodontitis damages the structure of the tooth and the surrounding ligament. It also destroys the bone underneath the gum line, loosening the tooth, which can result in tooth loss. Bacteria from the damaged tissues are released into the bloodstream and can also cause heart disease, such as endocarditis.

Signs of dental disease in cats

  • Bad breath

  • Red, inflamed or angry-looking gums

  • Drooling/excess salivation

  • A change in eating behaviour: reluctance to eat, chewing on one side, gulping food, preferring wet food, no longer wanting to chew normal treats, or vocalising when they chew something firmer than normal

  • A change in behaviour: hiding away, no longer wanting to interact with you or other cats in the household

  • Facial swelling: may indicate a tooth abscess

  • Tooth loss

Dental care for cats

Prevention: brushing your cat’s teeth everyday is the best way to remove and prevent plaque build up

  • Start to introduce the concept of oral hygiene as soon as possible

  • Use a cat finger toothbrush or a cat toothbrush and toothpaste. For example, Vetruus Stomodine or Virbac Enzymatic Toothpaste Fish Toothpaste

  • Your cat will take time to get used to having their teeth brushed. Advice on how to start brushing your cat’s teeth can be found on the Virbac website

  • If brushing isn’t possible, Logic Oral Hygiene Gel can be used without brushing. Apply it directly to the teeth and gums using a finger, or the applicator nozzle. For cats who will not allow this, try applying it to the top of their paw for them to lick off. With a malt flavour, it can be a good way to start introducing dental care

  • Other methods of plaque reduction, designed to compliment brushing, are available:
    • Water additives: for example, Virbac Aquadent

    • Oral rinses: for example, Virbac Hexarinse

    • Seaweed supplements: for example, ProDen PlaqueOff® Powder

  • Choose a good quality brand that is low in sugar if your cat will only eat wet food

  • Change your cat’s diet (as long as they are not on a specific veterinary diet for other health issues). Dry food is more abrasive than wet food, and may help to prevent plaque build-up. Specialised dental diets are designed to clean teeth by chewing. For example, Royal Canin Dental, or Proplan DH (Dental Health)

Treatment of dental disease in cats

Once plaque is attached to the tooth surface it can only be removed by mechanical means. Toothbrushing will remove mild plaque. However, ultrasonic descaling and polishing is needed for more advanced cases. A general anaesthetic will be required to enable thorough descaling and polishing, and to assess the health of the teeth and gums. Dental radiographs may be offered, which assess the tooth roots and identify any changes within the crown of the tooth. Whilst under anaesthetic, extractions of any teeth that have an infected root or fracture may be recommended.

FORLs in cats

The name FORL stands for feline odontoclastic resorptive lesion and these can affect cats of any age. These lesions are common, with some evidence suggesting 70% of cats over the age of five years have one or more FORLs. These lesions are where part of the tooth has been destroyed (resorbed) by the body, leaving a cavity. They can occur above the gingiva and be visible on the tooth, but many occur below the gingiva in the roots and are only detectable by radiographs. FORLs are very painful, and are grounds for extracting a tooth to relieve pain.

Any sudden change in demeanor, behaviour, eating habits including type of prefered food and chewing, can be a sign of dental pain. Equally many cats show no signs at all. For this reason it is always important to consider full dental radiographs at the time of dentals for all cats.

More information about feline dental care is available from Virbac.

When to see your vet

  • Your cat has halitosis

  • You see any of the signs of dental disease mentioned above

  • Your cat has a sore mouth, or a change in eating or chewing behaviour

Still worried?

Book a video appointment to have a chat with one of our vets.

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