Pirates of the Carribean: At World's End - Pirate Boy Wears Braces During Close Up
In the opening scene of the Pirates (at World's End) there is a hanging scene. A little boy is on the gallows and begins singing a solo song. Everyone joins in. During the close up scene of this boy singing, you can see his braces on his teeth.
Those are not braces. They're special caps on the boy's teeth (similar to what Johnny Depp wears on his teeth) that make the teeth seem as if they're very dirty.