Arctic hares have 28 teeth. There are four incisors at the front of the upper jaw, and on each side, a gap and six grinding teeth. On the bottom, the two incisors on the front are flanked on each side by a gap and five grinding teeth. The two larger incisors on the top are supported and strengthened by two smaller peg-like incisors behind. This trait is common to all lagomorphs.
Canadian Museum of Nature