Thank goodness, our incisor teeth are far different from those of squirrels.  While our teeth reach a certain length and do not grow any longer, such is not the case with squirrels.

       Take the gray squirrel, for example, its incisors grow roughly six inches per year.  This necessitates their having to wear them down.  They accomplish this task by gnawing on hard objects such as bark, wood, and nuts.  If they are unable to do so, the incisors get longer and longer and being to curl.  When this happens, the teeth eventually curl.  A squirrel with is malady can starve.  In some cases, the teeth can also grow into the animal’s mouth.  In extreme cases, the teeth will actually grow into the hapless creature’s brain!