Silva's chin has never been suspect. He doesnt even flinch when he gets hit. Honestly I don't he's ever been hurt (visable pain) besides that nasty heel hook.
"Let them see that their words can cut you, and you'll never be free of the mockery. If they want to give you a name, take it, make it your own. Then they can't hurt you with it anymore." - Tyrion Lannister