Rats are known for their prominent front teeth, which develop just over a week after they are born and grow continuously throughout their lives. An average rat’s teeth can grow from 4.5 (11.43 cm) to 5.5 inches (14 cm) every year.
To prevent their teeth from getting too long and becoming a hindrance, rats file them down by gnawing on objects, such as wood, brick, and even small animals. The constant wearing down of their teeth prevents rats’ front teeth from decaying and getting cavities.
An adult rat’s upper teeth have a growth rate of approximately 2.2 mm per week. If a rat loses a tooth for some reason, it will take an average of a month and a half to completely regrow.
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