Retained deciduous teeth occur when the roots of certain deciduous teeth, usually the canines, incisors, or premolars, do not resorb fully or at all. This results in adult teeth that must share their sockets with deciduous teeth, causing the adult teeth to grow in behind, in front of, or beside the deciduous teeth. These adult teeth often grow in at abnormal angles and positions, resulting in malocclusion, which can be one or a number of teeth misalignments. Retained deciduous teeth can also cause crowding, malformed jaws, early loss of adult teeth, pain, and numerous other dental health problems. It is extremely important that a kitten’s teeth be examined by a veterinarian, especially if it appears to you that the cat’s deciduous teeth have been retained. An adult cat that appears to have retained one or more deciduous teeth must also be immediately examined by a veterinarian.

A cat will have two full sets of teeth in its life. The first set, which is called the deciduous or baby teeth, consists of 26 teeth that begin coming in when a kitten is approximately three weeks old, a process that continues until around four months of age. The transition from deciduous teeth to permanent adult teeth begins soon after the deciduous teeth have come in, usually at around four months old. The permanent teeth erupt, or push through, into the same sockets that hold the deciduous teeth. When this process occurs normally, the roots of the deciduous teeth are resorbed and as the roots weaken and then disappear altogether. The deciduous teeth fall out as hollow shells. Sometimes these shells will be found sticking out of a chew toy or on the cat’s bed. It is also common and completely harmless that your cat inadvertently swallows the deciduous teeth shells while eating. The adult teeth then grow into the sockets, resulting in a set of 30 permanent teeth.

Retained deciduous present a number of symptoms, including:

Retained deciduous teeth are caused by the roots of deciduous teeth that do not resorb fully or at all to give way to the permanent adult teeth that are growing into that socket. It is suspected, but not known for certain, that retained deciduous teeth are likely a genetic condition.

Retained deciduous teeth in kittens can be noticed by pet owners or by veterinarians during routine examinations. If you or your veterinarian suspects that your cat has retained one or more deciduous teeth, your vet will likely administer the following diagnostic procedures:

If your cat is an adult that is found to have retained deciduous teeth, the vet will utilize many of the same diagnostic tools in order to determine which teeth may need to be pulled to make more room for the adult teeth that have grown into the same socket. It is imperative that an adult cat with this condition receive treatment as the cat may be in discomfort and is prone to oral infection. 

If your veterinarian diagnoses your kitten as having one or more retained deciduous teeth, the vet will need to pull the deciduous teeth as soon as possible. This will occur while your cat is under general anesthesia. Pulling these teeth will allow the permanent adult teeth to utilize the full socket and grow into proper position. This can be done at the same time as the neutering surgery if it has not yet been performed.

Adult cats with retained deciduous teeth may sometimes need to be treated by a veterinary specialist in dentistry and orthodontics. Extraction of teeth, especially when the patient is an adult animal and the teeth are the canine teeth, can be a very delicate and precise procedure that requires training and experience.

After a veterinarian has extracted the retained deciduous teeth, a kitten will likely recover from the surgery without any long term effects. The cat may be lethargic for a few hours to a few days from the anesthesia and uninterested in eating because of the pain and medication. The kitten will likely be given pain medication and antibiotics to prevent infection, and will be scheduled for a follow-up appointment with your vet. An adult cat that has had retained deciduous teeth extracted will likely need a great deal more recovery time than a kitten. Adult cats will also have follow-up appointments either with a veterinary dentist/orthodontist or with your veterinarian.