Caring for Mouse Teeth

Multi-colored mous in a hand.
Mice have teeth that continuously grow throughout their lives. Plougmann/E+/Getty Images

Not all pets have problems with their teeth but pet mice have unique teeth that can have serious issues. Some of the teeth in a mouse's mouth grow continuously throughout their life and these teeth need to be filed down to a normal length. Knowing how to help your mouse keep these teeth trimmed naturally and what to do if they don't is important for any mouse owner to know.

What Kind of Teeth Do Mice Have?

Dogs, cats, humans and many other species are born with no teeth, then grow baby teeth, and then lose those baby teeth so that their adult teeth can take their places. Mice, on the other hand, only have one set of teeth their entire lives. These teeth are called monophyodontal teeth and appear as young as ten days of age in a mouse.

Mice have twelve molars and four incisors and while the molars never grow, the incisors continuously grow which can sometimes cause problems for your mouse.These incisors are the front teeth and in mice they are naturally colored yellow. They are also much harder than human teeth. The two bottom incisors are almost twice as long as the two upper incisors but this can be hard to see since a large portion of these teeth are hidden underneath your mouse's lips.

Overgrown Mouse Teeth

Mouse teeth will grow very quickly with an entire tooth turnover rate of 35-45 days. The incisors, or front teeth, are usually easy to identify when they become very overgrown since they begin to stick out of the mouse's mouth. They will usually grow so long that they begin to curl and poke out between the lips. At this point they can become stuck on things, or worse yet, grow into the gums or roof of your mouse's mouth. Since the molars, or teeth in the back of the mouth, do not grow, they are not a problem like they can be in guinea pigs and rabbits.

Most mice will wear their incisors down to an appropriate length when they gnaw on their food but some mice are unable to do so if they are born with misaligned teeth or jaws. Misalignment or malocclusion may prevent a mouse from chewing normally and therefore not wear its teeth down. If trauma to the teeth or jaw occurs at some point in a mouse's life, this can also cause a problem with normal chewing and the normal wearing down of teeth. If a mouse has this issue, regular tooth trims will be needed to help it keep its incisors at a normal length and prevent a mouse from being unable to eat.

Tooth Trims for Mice

If you aren't sure if your mouse's teeth are a normal length, you'll need to gently pull back the cheeks and lips to make sure the teeth aren't curling into the mouse's mouth or cheeks. If the teeth are curling, they are too long and will need to be trimmed.

If done correctly, tooth trims are not painful and there are two common methods used to trim incisors. The first is by using regular nail clippers or blunt scissors to cut the teeth like you would a toenail. This method is not the preferred way to trim teeth since there is a high risk of cracking or splitting a tooth. Because of the force needed to use the clippers or scissors, the tooth can crack and can cause pain if it cracks up to the nerve or is trimmed too short. The second method of trimming teeth is with a handheld rotary tool, like a Dremel, with a cut-off wheel to slice the teeth. This method does require a bit more skill, along with anesthesia or sedation since mice are often squirmy and have small mouths, but can be easily performed by a trained veterinary professional. The only concerns are for trauma to the gums or lips if the wheel accidentally grazes them or if the tooth is trimmed too short. Cracking a tooth with a rotary tool is not typically a concern though the expense of anesthesia or sedation often causes people to choose to use clippers or scissors instead.