Here you go, actual 3D Cat scan rendering of the structural damage to the face of a rider without a full helmet. Look at the front of the mandible (jaw) it's completey snapped in half.
http://www.flickr.com/photos/roentge...7601198404570/
I wonder how long it will take some ignorant bastard to jump in this thread an insist that in fact full face helmets are
MORE dangerous because they break your neck? Before you do, think of what a wholey stupid argument that is and just don't post it.