SYMPTOM
Chronic gingivitis
The gums look red and swollen along the edge where they meet the teeth, and may bleed when touched or during eating. Bad breath is common. Some cats drool, paw at the mouth, groom less or eat less, but many show no obvious change even when the inflammation is marked, because cats often hide oral pain.
Periodontal Disease (Plaque-Induced Gingivitis)
Bacterial plaque accumulating along the gumline triggers a localised inflammatory response confined mainly to the gum margin. This is the most common cause of gingivitis in cats and tends to progress gradually with age in the absence of routine dental care.
Tooth Resorption
Cells called odontoclasts break down tooth structure, usually starting on the root surface at or below the gumline, and the gum next to the affected tooth is often inflamed. In advanced cases the gum can grow over what remains of the tooth. More than 60% of cats are reported to develop tooth resorption during their lifetime, it becomes more common with age, and it can affect one or several teeth at once.
Feline Chronic Gingivostomatitis
An exaggerated immune response to oral bacterial and viral antigens produces inflammation that extends well beyond the gumline into the back of the mouth, out of proportion to the amount of visible plaque present. Calicivirus infection is frequently implicated, and the condition typically develops in young to middle-aged cats.
Retroviral Infection (FIV/FeLV)
Feline immunodeficiency virus and feline leukaemia virus alter immune regulation within the mouth, allowing gingival inflammation to become more severe and harder to resolve than plaque levels alone would suggest. Testing is often considered in cats whose gingivitis is disproportionately severe or resistant to routine dental care.
Juvenile-Onset Gingivitis and Periodontitis
Gum inflammation that starts around the time the adult teeth come through, usually first diagnosed between about 6 and 12 months of age. In some young cats it extends into the deeper tissues, causing gum recession, loose teeth and loss of the bone that holds the teeth (juvenile-onset periodontitis). Many cats outgrow it by about two years of age, but whether the teeth are kept depends on regular dental cleaning and home care until then.
Why timing matters
Early observation
Early recognition allows prompt assessment and intervention if needed.
Later presentation
Persistent or worsening signs may indicate progression requiring attention.
Gingivitis on its own can be reversed by removing plaque, which returns the gum to a healthy state. Once inflammation spreads to the bone and ligament that hold the teeth (periodontitis), that loss is not readily reversed.
Conditions commonly associated
Feline Immunodeficiency Virus (FIV)
Oral inflammation is common in FIV-positive cats and may be more severe than in uninfected individuals.
Dental Disease in Cats
Chronic gingivitis in cats can be a feature of dental disease, where plaque and calculus accumulation provoke ongoing gingival inflammation. The condition may develop silently over time, with inflammation persisting even in the absence of overt discomfort signals.
Tooth Resorption
Tooth resorption in cats may be accompanied by chronic gingivitis, as the progressive destruction of tooth structure often triggers localised inflammation of the surrounding gum tissue. The gingivitis in this context can reflect the immune response to exposed or degrading dental material beneath the gum line.
Feline Calicivirus
Feline calicivirus is detected more often in cats with chronic gingivostomatitis than in healthy cats. The virus appears to replicate little, if at all, in the inflamed tissue, so it is thought to contribute to a persistent immune-driven inflammation rather than cause it directly.
Bartonellosis
One early study suggested Bartonella might play a part in chronic gingivostomatitis in cats, but later studies found antibodies and organisms no more often in cats with oral disease than in healthy cats, so a link with gum inflammation has not been shown.
When to explore further
When the symptom is persistent or worsening
When other signs are present alongside
When daily activities or quality of life are affected
When there is uncertainty about the cause
Noting when this symptom occurs, any triggers, and how it changes over time can provide useful information for veterinary discussions.
Last reviewed: 9 October 2026 · Dr Alastair Greenway MRCVS