Pet rats need to gnaw, and it's not just because they have nothing better to do. If your rat doesn't gnaw on hard substances regularly, his front teeth can grow so long he has trouble eating. Your rat can also develop cavities, just like you do, but a proper diet and regular vet visits can help.
The biggest dental problem with pet rats is with their front incisors. Their front teeth grow continuously, so they must gnaw on hard items, such as sticks or dog biscuits, to help file down their incisors. If they don't keep them gnawed down, the incisors can grow so long your rat can't close his mouth properly. Some rats have incisors that don't align properly, which keeps one or more of the incisors from getting enough friction during gnawing to be filed down.
If your rat can't or won't gnaw down his front teeth, your vet can help by using a high-speed drill to file down the incisors. Don't try clipping them with nail clippers or other tools at home; this can crack or fracture the teeth, exposing your rat to infection. In severe cases where the teeth will never meet properly and can never be filed down naturally through gnawing, your vet might pull the teeth.
Rats are often used in cavity studies because their teeth react much like yours do. When exposed to sugary foods or drinks, your rat can develop cavities. He can also get the bacteria that causes cavities from you, when you give him kisses or feed him something you've already bitten. Cavities in the incisors aren't usually a problem because they grow so fast and are filed off. However, cavities in the back molars can be painful and become abscessed.
Your vet can't thoroughly check your rat for cavities unless your pet is sedated, so check with your vet about how often he needs a thorough check. If your rat is drooling, has a swollen cheek, has bad breath or has lost his appetite, a cavity could be responsible. Don't give him real or artificial sugars, and make sure he has lots of crunchy food to help clean away tartar. Keep him away from your table scraps. When a cavity develops, your vet can help you decide the best course of action, which might be pulling the tooth.
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