The etiology is unknown, however theories supporting an autoimmune response mediating cellular and humoral factors, calici virus, and metabolic imbalances relating to calcium regulation have been proposed. Patients effected with FORLs may show hypersalivation, oral bleeding, or have difficulty apprehending food. A majority of effected cats do not show obvious clinical signs. Most times it is up to the clinician to diagnose the lesions on oral examination. The lesion often erodes into the sensitive dentin, causing the cat to show pain with jaw spasms when the EOR is touched.
Intraoral radiology is helpful in making definitive diagnosis and treatment planning.
The lesion is usually minimally sensitive in because it has not entered the dentin. In Stage 2, lesions penetrate the enamel and dentin. These teeth may be treated with self cured or light cured glass ionomer restoratives, which release fluoride ions to desensitize the exposed dentin, strengthen the enamel, and chemically bind to tooth surfaces. In Stage 4 FORL, the crown has been eroded or fractured. Gingiva grows over the root fragments leaving a sometimes painful bleeding lesion upon probing.