This is a condition we can see in young cats, usually around 6-9 months of age. It is characterized by bright red gums and teeth with little to no visible tartar.  The exact cause is unknown; however, potential causes may include: viruses, breed disposition (more common in certain purebred cats such as Persians, Siamese, and Abyssinians), environmental influences, immunosuppression, and, of course, plaque and tartar buildup.
 
It often starts with mild gingivitis localized to specific teeth, but may then progress to severe inflammation and bleeding of the tissues around the teeth. Treatment requires removing and preventing plaque accumulation through professional dental cleanings every 3-6 months, along with aggressive home care. Home care may include daily toothbrushing, sprays, rinses, or water additives.

If left untreated, the chronic inflammation can result in tooth resorption and bone loss around the teeth, requiring extractions. The good news is that many cats seem to outgrow the disease by age 2. Unfortunately, those cats that do not respond will require further treatment.