What causes oral swellings in cats?
Oral swellings are never normal. There are many causes of oral swellings including local trauma, infection, fluid accumulation, and tumors.
Above: Benign tumor surrounding upper cheek teeth. Below: Swelling due to trauma from the upper cheek tooth.
What should I do if I see a swelling in my cat’s mouth?
Book an appointment to have your veterinarian examine your cat and the swelling. Some oral swellings can be painful to touch, so to protect yourself from being bitten, do not touch the swelling.
What will my veterinarian do?
Your veterinarian first needs to determine the cause of the swelling. Unless the cause is obvious from a visual examination, diagnostic tests are required. Typically, diagnostic tests include intraoral radiographs (X-rays) and some form of cell or tissue sampling of the oral swelling. Additional laboratory tests such as a complete blood count (CBC) and a serum biochemistry profile may also be performed.
"Your veterinarian first needs to determine the cause of the swelling."
Most often, a general anesthetic is required to obtain a sample of an oral swelling or oral mass. Various techniques include a fine needle aspiration (FNA) or a biopsy. Your veterinarian will recommend the sampling technique best suited for your cat.
How are oral swellings treated?
Treatment will depend on the cause of the oral swelling. If the swelling is cystic (fluid-filled) and associated with a missing, unerupted tooth, then it is possibly a dentigerous cyst. Surgery will be performed to remove the tooth, drain the cyst and remove the cyst lining. The cyst lining will be sent to a veterinary pathologist for evaluation. If the swelling is associated with a fractured tooth then it may be due to a tooth root abscess. These teeth may be treated with extraction or standard root canal therapy.
Left: Facial and eye swelling due to infection from retained tooth roots (left). Right: Swelling resolved following surgery (right).
What is the prognosis for my cat?
The ultimate outcome will depend on the underlying cause. In case of cysts, trauma, and infection, the swelling will usually be cured with veterinary treatment. In cases of cancer, a biopsy will determine how likely the cancer is to respond to surgical therapy.