By WCCO-TV Staff

MINNEAPOLIS (WCCO) — It was a big day at the dentist for a big cat up north.

Lilly, a 350-pound lioness who lives at the Lake Superior Zoo in Duluth, had a root canal performed Sunday — an operation that took about three hours to complete.

Dr. Louise Beyea, a veterinarian at the zoo, says staff noticed a broken tooth during a routine checkup.

(credit: CBS)

“The keepers have trained the cats to open their mouth on cue, so they can do that several times during the week and make sure there’s no problems in the animal’s mouth,” Beyea said. “And when they did that, they were immediately able to see that things were different from the day before, and that Lilly had broken off the large canine tooth on the top of her jaw.”

Lilly will need to lay off the bones for a few weeks, and stick to softer foods.