Gingivitis and stomatitis both involve inflammation of the mouth tissues and can be painful and affect your cat’s health.
Gingivitis is inflammation of the gums. Every time a cat eats, bacteria, proteins, and dead cells form a thin film over the hard surface of the tooth. This thin film is known as plaque and can build up on the tooth’s surface when the bacteria grows. Within a few days, minerals in the saliva can cause the plaque to harden into dental calculus (or tartar). Dental calculus is difficult to remove except during a professional dental clean under anaesthesia.
Above: A cat with severe dental disease and dental calculus (or tartar) (highlighted by the orange arrows) (images reproduced with kind permission from Dr Rebecca Nilsen).
Above: For comparison, a cat after dental cleaning under anaesthesia now showing normal healthy and clean teeth (image reproduced with kind permission from Dr Rebecca Nilsen).
As plaque and tartar continue to accumulate and extend below the gum line, the gums can become inflamed and swollen around the affected tooth, leading to gingivitis. Gingivitis refers to inflammation of the gingiva which is the gum that surrounds the teeth. If gingivitis is not addressed, it can cause periodontal disease, a condition where bone loss can occur and the supporting structures of the tooth (gingiva -gums, periodontal ligament, cementum and supporting bone) can be damaged.
Above: Tooth of a cat with gingivitis (shown by reddening of the gum, highlighted by the orange arrow), showing what looks like a relatively normal looking tooth (image reproduced with kind permission from Dr Tara Cashman, President of the Australian Veterinary Dental Society).
Below: The same tooth showing extensive destruction of both the tooth root and crown (the part above the gum line). This shows on the X-ray as grey fluffy looking areas (highlighted by the orange arrow and circle), compare this to the adjacent healthy tooth root and crown showing on the X-ray as a solid white tooth (highlighted by the green arrow and circle). This is a feline resorptive lesion and is a very painful condition. (Image reproduced with kind permission from Dr Tara Cashman, President of the Australian Veterinary Dental Society), demonstrating the importance of dental X-rays to uncover serious dental disease which could otherwise be missed.
Stomatitis is inflammation of the tissues in the mouth, including the gums, cheeks, back of the throat, tongue, or the inside of the lips, and may affect large areas in the mouth.
Feline chronic gingivostomatitis
Cats can suffer from a specific condition known as feline chronic gingivostomatitis (this is also referred to as lymphocytic plasmacytic gingivo-stomatitis complex (LPGC), or chronic gingivostomatitis) . Gingivostomatitis is a disease process involving severe and chronic inflammation, and ulceration of the gums and tissues in the mouth. The Llesions that occurappear are more severe than gingivitis or stomatitis alone. This condition can have severe welfare impacts if not addressed due to pain, and the health, behavioural, and psychological effects it can have on your cat. The cause of gingivostomatitis is still unknown. It is thought to be multifactorial and associated with both infectious and non-infectious causes. These include disease pathogens (for example, Feline Immunodeficiency Virus, Feline Calicivirus, and Feline Leukaemia Virus), dental disease (tooth resorption and periodontal disease), and hypersensitivity (due to an immune-mediated inflammatory reaction where the cat’s immune system responds too aggressively to the presence of bacteria or other infectious agents in the mouth, or food allergies) . Cats can become affected at any age, and all breeds of cats can develop this disease.
What clinical signs of gingivostomatitis might I see in my cat?
Gingivostomatitis often appears as intensely red, inflamed, ulcerated lesions across the back of the mouth, near the base of the tongue. These lesions will often bleed easily. Your cat may have difficulty eating (especially kibbles or hard food), a lack of appetite and subsequent weight loss, excessive salivation (or drooling), bad breath, decreased grooming, and may seem depressed and lacking in energy (often due to pain) . Cats may also show other signs related to mouth pain, such as pawing at the mouth.
What are the treatment options for gingivostomatitis? 
Treatment depends on the extent of the disease. Initially all the teeth are usually cleaned thoroughly under anaesthetic by a veterinarian. The cat then has follow up home care to help keep the teeth and mouth as clean as possible; antibiotics and anti-inflammatory medications may also be used. Pain management is important and, depending on the response to treatment (which is very variable), stronger anti-inflammatory drugs medications and treatments drugs that reduce the excessive immune response may be needed . In some cats who are severely affected, removal of some or all of the teeth may be helpfulmight help, possibly because it can help removes the source of bacteria in the mouth which are is triggering the aggressive immune response causing the inflammation. If this condition is not treated and it progresses, it becomes a serious welfare issue since it causes severe pain and distress.
If your cat is affected, your veterinarian can advise you on the best ways to manage and treat this disease.
Make sure your pet gets a vet check up every year
Annual visits to your veterinarian for a general health examination and dental check-up are very important. These annual check-ups help to identify and address any issues early and keep your cat as healthy as possibleier and more comfortable.
 Lommer M (2013) Oral inflammation in small animals. Veterinary clinics of North America: Small Animal Practice 43 (3): 555-571. doi: 10.1016/j.cvsm.2013.02.004.
 Healey K (2007) Prevalence of feline chronic gingiva-stomatitis in first opinion practice. Journal of Feline Medicine and Surgery 9 (5): 373-381. doi: 10.1016/j.jfms.2007.03.003.
 Winer J et al (2016) Therapeutic management of feline chronic gingivostomatitis: A systematic review of the literature. Frontiers in Veterinary Science 3:54. doi: 10.3389/fvets.2016.00054. https://www.frontiersin.org/articles/10.3389/fvets.2016.00054/full