What happened to the handprint?!

Jensen at a convention said that actually the writers totally forgot about the handprint that's why we haven't seen it anymore but anyway that's the behind the scene explanation...the "on camera" explanation is that when Castiel healed Dean in Swan Song he healed the handprint too.

The first, and if I remember correctly, only time we saw Castiel's handprint was shortly after Dean had been freed from Hell. My guess is that it just faded over time, like a scar.

Well Dean was resurrected more than once, so maybe when the resurrection healed him, it healed the handprint as well.