During the scene when Strykers soldiers are raiding Professor Xaviers mansion, one girl wakes up in bed screaming really high pitched (Siryn?). There is a close up of her mouth wide open while she is screaming and you can see that she has braces on her upper teeth. They look like they are ceramic though.

Bedeutungslose Szene: Ein Mädchen wacht auf und für 1 sec. sind clear braces zu sehen.