Interactive 3-D Skull ModuleThe human head is comprised of 23 different bones. The Cranium, also called the "Skull," describes the skeleton that comprises all of the bones of the head, face and lower jaw (i.e., the mandible). In an adult, various bones of the cranium are paired (i.e., consist of a left and a right) while others which cross the mid-sagittal plane are unpaired.