THE DENTAL CARE SERIES By Jan Bellows D.V.M. DipAVDC All Pets Dental Clinic

A common feline oral malady is the feline oral resorptive lesion (FORL). A majority of the affected cats are older than 4 years. These tooth defects have been called cavities, neck lesions, external or internal root resorptions, and cervical line erosions. FORLs are usually found on the outside of the tooth where the gum meets the dental surface. The lower jaw premolars are mostly affected, however FORLs can be found on any tooth.

The cause is unknown, but theories supporting an autoimmune response, calicivirus, and metabolic imbalances relating to calcium regulation have been proposed. The resorptive lesion often erodes into sensitive dentin, causing a cat to show pain and jaw spasms whenever the lesion is touched. Patients affected with FORLs may show increased salivation, oral bleeding, or difficulty eating. Most times it is up to the veterinarian or astute owner to diagnose FORLs.

The FORL can present in many stages. Initially (stage 1) an enamel defect is noted. The lesion is usually minimally sensitive because it has not entered the dentin. Therapy of this defect usually involves a thorough cleaning, polishing, and smoothing out the defect. In stage 2, the lesion penetrates enamel and dentin. These teeth may be treated with restoratives which release fluoride ions to desensitize the exposed dentin, strengthen the enamel, and chemically bind to tooth surfaces. The long term (greater than 2 years) effectiveness of restoration of stage 2 lesions have not been proven. Restorative application to the FORL does not automatically stop the progression or the disease. Intraoral x-rays are essential to determine if the lesions have entered the pulp chamber (stage 3) requiring either root canal therapy or extraction. Often x-rays will reveal resorption of the tooth root necessitating extraction. In stage 4 FORLs, the crown has been eroded or fractured. The gum tissue grows over the root fragments leaving a sometimes painful and/or bleeding lesion upon probing. Treatment of choice is flap surgery and extraction of the root fragments that appear to be inflamed or painful to the patient.

Dr. Jan Bellows is a board-certified veterinary dentist. His office, Hometown Animal Hospital and Dental Clinic, is located at 17100 Royal Palm Boulevard in Weston, Florida. He can be reached for consultations at 954-349-5800.

Date Published: 6/17/2002 5:47:00 PM
Date Reviewed/Revised: 04/05/2007