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Sore Mouth (Stomatitis) in Dogs

Stomatitis is inflammation of the mouth, gums, and tongue. It is usually caused by periodontal disease or foreign bodies caught between the teeth or embedded in the tongue. Occasionally, it follows mouth lacerations and burns of the mucous membranes.

Stomatitis is an extremely painful condition accompanied by drooling, bad breath, refusal to eat, difficulty chewing, and reluctance to permit an examination of the mouth. The inside of the mouth is red, inflamed, and sometimes ulcerated. The gums often bleed when rubbed.

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Stomatitis can be a local manifestation of a systemic disease. It is seen in dogs with kidney failure and uremia, diabetes mellitus, hypoparathyroidism, leptospirosis, distemper, and autoimmune skin diseases.

Trench mouth (St. Vincent’s stomatitis; necrotizing ulcerative stomatitis) is an exceptionally painful stomatitis caused by a variety of bacteria. There is a characteristic serious mouth odor, accompanied by brown, purulent, slimy saliva that stains the front of the legs. The gums are beefy red and bleed easily. Ulcerations occur in the mucous membranes. Some cases are initiated by periodontal disease.

Thrush (yeast stomatitis) is an uncommon stomatitis seen chiefly in dogs who are receiving broad-spectrum antibiotics that destroy normal bacterial flora and allow the growth of yeast. Thrush also occurs in dogs with compromised immunity associated with chronic illness. The mucous lining of the gums and tongue are covered with soft white patches that coalesce to produce an adherent white membrane. Painful ulcers appear as the disease progresses.

Recurrent stomatitis occurs where jagged, broken, or diseased teeth make repeated contact with the mucous lining of the lips, cheeks, or gums, causing traumatic ulcers of the mouth. A bacteria and a fungus are quite commonly cultured from these ulcers.

Treatment: In most cases periodontal disease is present as a cause or a contributing factor. Your veterinarian may recommend a thorough cleaning of the dog’s mouth under anesthesia. This affords the opportunity to treat dental calculus, decayed roots, and broken teeth-treatments that are all essential to cure the problem. The dog is then placed on an appropriate antibiotic.

It is important to diagnose and treat any systemic cause of the stomatitis.

Aftercare at home involves rinsing the mouth with a 0.1 or 0.2 percent chlorhexidine solution (Peridex or Nolvadent) once or twice a day. Soak a cotton ball and gently swab the gums, teeth, and oral cavity. You can use a plastic syringe and squirt the mouth wash directly onto the gums.

Feed a soft diet consisting of canned dog food diluted with water to a mushy consistency. Your veterinarian may prescribe a pain medication such as Etogesic or Deramax. B-complex vitamins that contain niacin may be of benefit.

Thrush is treated with topical Nystatin or an antifungal drug such as ketoconazole or itraconazole.

WebMD Veterinary Reference from "Dog Owner's Home Veterinary Handbook"

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