Tooth resorption

Tooth resorption is a disease in which cells called odontoclasts break down the tooth itself, usually starting at the neck of the tooth near the gum line and spreading into the crown and root. It was once called a cat cavity, but it is not caused by bacteria in the way a human cavity is, and its cause is not fully understood. Studies find it in a large share of adult cats, and the risk rises with age.

The lesions often sit under inflamed gum tissue, so owners rarely see them. Signs include drooling, bad breath, chewing on one side, dropping food, reluctance to eat hard food, sneezing when chewing, and sensitivity of the jaw when it is touched. Many cats show no sign at all because they hide discomfort, so the disease is often found during an exam.

A vet finds resorption by probing the teeth and taking dental X-rays under anesthesia. Because the lesions are painful and progress, treatment is usually extraction of the affected tooth, or removal of just the crown in some cases. Fillings do not work well. Brushing and cleaning do not prevent it, though good oral care helps with periodontal disease. Ask your vet about dental X-rays and how often to check your cat's mouth.