Mouth UP. The joint tears and the jaw splits above and below. Organic-looking teeth lay within.
Reichu: What I translated as "organic-looking" is actually seibutsuteki na, or "like a living creature". Suffice to say, those aren't the Eva's real teeth.
Sharp-kun: Shows how much thought Nerv put into the aesthetics, though. They even designed the head so it looks cool when the unit goes berserk.
