Feline dental care is perhaps the most overlooked and under-treated area in small animal medicine. Cats are affected by many of the same dental problems that affect dogs (periodontal disease, fractured teeth, and oral masses) in addition to special syndromes (tooth resorption, gingivostomatitis).
More than fifty percent of cats over three years old will be affected by tooth resorption (TR). These tooth defects have also been called cavities, neck lesions, external or internal root resorptions, or cervical line erosions. Teeth affected by lesions will erode and finally disappear when they are absorbed back into the cat’s body. The root structure breaks down; then the enamel and most of the tooth become ruined, and bone replaces the tooth. This most commonly happens where the gum meets the tooth surface. Some molars are most commonly affected; however, tooth resorptions can be found on any tooth. The reason for the resorption is unknown, but theories supporting an autoimmune response have been proposed.
Cats affected with tooth resorption may show excessive salivation, bleeding in the mouth, or have difficulty eating. Tooth resorptions can be quite painful. A majority of affected cats do not show obvious clinical signs. Most times it is up to the clinician to diagnose the lesions upon oral examination. Diagnostic aids include a probe or cotton tipped applicator applied to the suspected resorption; when the probe touches the lesion, it causes pain and jaw spasms. Radiographs are helpful in making definitive diagnosis and treatment planning.
Tooth resorptions can be seen in many stages:
- Stage 1 (TR 1): Mild dental hard tissue loss.
- Stage 2 (TR 2): Moderate dental hard tissue loss.
- Stage 3 (TR 3): Deep dental hard tissue loss; most of the tooth retains its integrity.
- Stage 4 (TR 4): Extensive dental hard tissue loss; most of the tooth has lost its integrity.
(a) Crown and root are equally affected;
(b) Crown is more severely affected than the root;
(c) Root is more severely affected than the crown.
- Stage 5 (TR 5): Remnants of dental hard tissue are visible only as irregular radiopacities, and has completely covered the gum.
Radiographic appearances of the resorptions vary. If the periodontal ligament is visible, the tooth should be extracted via flap exposure. If the periodontal ligament is not visible, crown reduction and gingival closure can be performed.
Cats can also be affected by gingivostomatitis, an inflammation. The cause of this disease has not been determined but an immune-related cause is suspected. Signs in an affected cat include difficulty swallowing, weight loss, and excessive saliva. An oral examination will show many abnormalities. Radiographs often reveal moderate to severe periodontal disease with bone loss.
All stages of tooth resorption can be seen by the veterinarian and on x-rays. Managing a case of gingivostomatitis can be challenging. Oftentimes attempts at conservative therapy are not affective, nor is medical care. Extracting specific teeth usually resolves the syndrome in sixty percent of the cases. Twenty percent require medication, typically prednisone. Twenty percent respond poorly. A carbon dioxide laser has also been used with some success.
Cats are also affected by cancer in their mouths. Squamous cell carcinoma (SCC) is the most common type of oral cancer. Less common feline oral malignancies include melanoma, fibrosarcoma, lymphosarcoma, and undifferentiated carcinomas.
Not all feline oral swellings are malignant. Cats are frequently affected by reactions to foreign bodies, problems from dental disease, tumor-like masses, infections, and growths in the nose or throat.
Biopsies are essential for diagnosis.
Some cats have orthodontic problems. Commonly a lance or saber-like projection of canine teeth occurs, especially in Persians. Cats are also affected with wry bites that are uneven.