Rat/Mice Diseases - Overgrown teeth & malocclusion

 
malocclusion in rat
  • Malocclusion, the medical term for improper alignment of the teeth, is one of the most common veterinary problems seen in rodents like rats and mice whose teeth continuously grow throughout their lives.
  • Rats and mice are monophyodont, having only one set of teeth during their lifetime. Under normal circumstances rats and mice have 4 opposing incisors, two smaller on top and two longer curved ones on the bottom.
  • The constant actions of cropping with the front teeth and chewing with the cheek teeth keep the teeth well aligned and provide constant and even wear on all the teeth, preventing overgrowth.
  • When malocclusion is present, the teeth continue to grow without being properly worn by the opposing teeth. The incisors can curl and twist, and if not kept trimmed results in trauma to the soft palate, infection, and abscesses, which in turn will eventually lead to the rat and mice starving.
  • Malocclusion (improper meeting of the upper and lower incisors) may be due to injury (such as loss of a tooth due to root damage or trauma), dental disease, genetics, tumors, or other non infectious reasons.
  • All owners should check their rat’s or mice teeth occasionally to make sure they’re normal. If your rat and mice has missing teeth, malocclusion, or unevenly worn teeth, check the length of his incisors frequently to see if trimming is needed.

  • Symptoms:
    • Drooling
    • Decreased food intake
    • Dropping food
    • Teeth growing abnormally long
    • Selective appetite for softer foods only
    • Rub at its mouth with its feet
    • Foul odor from the mouth
    • Weight loss
    • Sores developing in or near the mouth

  • Trimming overgrown teeth
  • Treatment:
    • Treatment for malocclusion involves trimming ("filing" or "clipping") of the teeth. The incisors can usually be trimmed without the use of anesthesia. Anesthesia is almost always necessary for trimming of the molar teeth.
    • Depending upon the growth rate the affected teeth need to be trimmed every two weeks to every 2 months.
    • Antibiotics may be prescribed if infection is suspected, but are not routinely necessary if there is no suspicion of infection.
    • In severe cases, the incisor teeth can be surgically removed. This is a permanent procedure and must be discussed with your veterinarian.

  • Prevention:
    • Feed your pet good quality pellets high in fiber.
    • Fresh hay should be available at all times to encourage grinding of the back teeth. Stem hay is better than commercially packaged leaf or "hay cubes."
    • Check your pet's incisor teeth periodically since malocclusion is not cured but managed. Ask your veterinarian to check the incisor and molar teeth any time your pet gets examined. The molars should be checked at least once a year, but preferably twice a year.
    • With genetic malocclusion there is no prevention, but rats and mice with this disorder should not be bred.
    • Keeping your pet from areas where he/she will fall will help to prevent injury-related malocclusion. This is especially important when dealing with elderly rats and mice or pets that have disorders that affect balance.