Why Do Rats Lose Their Teeth?
WouterRats have sixteen teeth: four incisors on top and four on bottom, and 12 molars on each side. They wear these teeth down by gnawing and bruxing, which keeps them sharp. If they left their teeth unchecked, they would grow at an 86-degree angle, preventing them from closing their mouth and leading to their death.
Rats have a three-stage tooth development process. The first set of molars erupts on the 19th day of life, and the second and third erupt two weeks later, on the twenty-first and thirty-fifth days. This is when they can wean themselves from their mother. Two weeks later, on the thirty-fifth to forty-fifth day, the third set comes in. After 125 days, molar growth slows considerably, but it continues to grow.
If you observe a healthy rat’s teeth, you will notice that the bottom incisors should be twice as long as the top. This is because the incisors should meet and grind against one another. Rats usually use their incisors to bite, but only when they feel threatened or trapped. Their molars, which are also called cheek teeth, are used for chewing and gnawing.
It is not known exactly why rats lose their teeth, but a number of factors contribute to their deterioration. In addition to a lack of chewable food, rats suffer from malocclusion, which causes their teeth to overgrow. Their incisors are overgrown, which prevents them from grinding together and wearing them down. When this happens, their mouth can be extremely hard to use.
