Gingivitis is the most common type of oral disease among cats and it's as prevalent among cats as it is in dogs and humans. However, cat gingivitis may involve more than the simple swelling and bleeding of the gums you might experience in your own mouth. Indeed, in some cases, it can be life-threatening.

Because it's so common — as well as potentially complex and severe — it's important for cat parents to understand the causes and signs of feline gingivitis, as well as basic treatment and prevention measures.

What Is Gingivitis?

Gingivitis is an inflammation of the gums. It mostly occurs in senior cats, when plaque builds up and the gums respond with swelling, redness, bleeding and sensitivity. Plaque is an accumulation of bacteria combined with substances that turn the mix into a concretion that adheres to the teeth. Plaque leads to swelling of both the gums and the periodontal ligament — the structure that attaches teeth to the underlying bone.

When only the gums react, the result is gingivitis, which literally means inflammation of the gums. When the disease progresses and the periodontal ligament reacts to plaque with swelling and deterioration, the resulting disorder is referred to as periodontitis, or periodontal disease. The terms gingivitis and periodontal disease are often incorrectly used interchangeably, so it's important to distinguish them from one another.

Causes of Gingivitis in Cats

In most cats, gingivitis is the result of gradual plaque accumulation, a process that occurs as cats age, if they don’t get appropriate dental care at home. There's tremendous variation in the degree to which cats' gums react to plaque. Some cats seem to accumulate large amounts of plaque with a minimum of gingivitis while other cats' gums react more severely. 

A cat's unique degree of gingivitis and periodontitis can be affected to a degree by genetic susceptibility and will also depend on how much dental care they get at home. But gingivitis in cats can also be affected by certain conditions, including:

• Infectious diseases: Feline leukaemia virus and feline immunodeficiency virus are the most common infectious diseases that can lead to gingivitis.
• Tooth resorption: This phenomenon used to be called Feline Odontoclastic Resorptive Lesions (FORL). It’s a common condition in cats where the body starts to resorb the teeth from the roots. It’s very painful and is diagnosed by taking x-rays of the teeth and gums. The only treatment is removal of the affected teeth and, in some cases, this means all the teeth. Although this sounds extreme, cats do very well afterwards and, most importantly, are pain-free. During tooth resorption, gingivitis is common.
• Juvenile-onset gingivitis: Teething cats typically experience mild gingivitis, but severe gingivitis can also occur after adult teeth come in.
• Fractured teeth: Traumatic conditions can trigger gingivitis.
• Malocclusions: Misaligned teeth, seen commonly in flat-faced (also called brachycephalic) cats, and other orthodontic abnormalities may lead to gingivitis.
• Eosinophilic granuloma complex: This inflammatory disease can sometimes affect the lips, gums, tongue and, consequently, nearby teeth.
• Gingival hyperplasia: While less common in cats than dogs, gum overgrowth leads to gingivitis in both species.
• Gingivostomatitis: This disease is the result of an extreme overreaction of the gums and surrounding oral tissues to dental tissues and plaque, and can cause a debilitating amount of pain. Cats with the condition may be unable to eat or drink. Sometimes the pain and inflammation is so severe that a complete extraction of all teeth is the only remedy. This sounds drastic but most cats do really well afterwards and have a vastly improved quality of life.