Rodents have open-rooted dentition, meaning that their teeth grow continuously throughout their lives. The incisors, which are specialized for gnawing, continue to grow and curve.

What animals have continuously growing teeth?

A monophyodont is an animal with only one set of teeth that grows continuously throughout its life, such as platypuses, sloths, walruses, seals, narhwals, dolphins, and most toothed-whales.

What teeth continuously grow?

A squirrel's teeth grow continuously. Their incisors can grow up to six inches per year, but stay short due to the constant wear they receive.