Polar Bear Boris Gets A Root Canal At Washington's Point Defiance Zoo & Aquarium (PICTURES)

A nine foot tall polar bear weighing 922 pounds (66 stone) has successfully undergone a root canal.

Boris, a resident at Washington’s Point Defiance Zoo and Aquarium, underwent the four-and-a-half hour procedure on Saturday.

The 27-year-old bear also received minor surgery on an injured eyelid and a general check-up by a team of staff led by oral and maxillofacial surgeon Jim Reed, The Seattle Times reported.

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He knows the drill: Boris during his four-and-a-half hour long procedure

Boris is one of three polar bears at the Zoo's Arctic Tundra exhibition, which mirrors a coastal setting near Point Hope, Alaska.

He was rescued from a Mexican circus in Puerto Rico ten years ago.

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