Superheroes like Batman, Thor and the Incredible Hulk have been used to promote a wide range of products over the decades, but this may be the first time they've been enlisted to promote dental floss.

Produced by Ecuadorean agency Independiente, this series of ads for Oral-B cleverly uses dental floss to create instantly recognizable outlines of the Dark Knight, the thunder god and the Green Goliath. They're probably not authorized by Marvel or DC Comics -- there's no trademark information to be seen -- but they're clever nonetheless.

(via Design Taxi)