Man Bites Man/Analysis

Humans have strong, if blunt, teeth and impressive biting strength for their size. Biting causes about the worst flesh damage unarmed combatants can do to one another: pretty much every other strike involves either blunt force trauma or relatively slow strangulation.

Obviously it's got a lot of drawbacks: disease risks (for both sides), an extremely limited reach as well as being a very committed attack: the attacker can't defend their head while using it. It's also, technically speaking, extremely grody. Most of the time, biting is a last resort attack.

In the martial arts, biting is a documented method of escaping a hold while one's limbs are pinned. It is taught in only the most pragmatically brutal disciplines: actually using it in anything other then a real world life and death situation is near unheard of. Proper utilization requires racking off a piece of flesh to convince even the most determined of attackers to let go.

However, it does have a very large psychological impact. Having someone try to bite you, or even lunge at you snapping, is far more disturbing than seeing a punch coming, due to the fact that it taps into a far more primal response. It's often used as a way of getting someone to rear back, or flinch, so that you can get a hand free or get enough space to use your head.