Cranium

Two sets of bones

Your skull is made up of two sets of bones - the bones of your face and the bones of your cranium, which make up your forehead and the back of your head.

Cranium

Your cranium is the large bony case that surrounds your delicate brain, protecting it from bumps and knocks. It is made up of eight large flat bones, joined together by fixed joints known as sutures. Your frontal bone forms your forehead, and the tops of your eye sockets. Most of the top and sides of your head are formed by two parietal bones. And the back of your skull is formed by your occipital bone which has an opening in it where your spinal cord connects to your brain.

Facial bones

The fourteen bones at the front of your skull hold your eyes in place and form your facial features. Your mandible, or jawbone, is the largest, strongest bone in your face. It holds your lower teeth in place and you move it to chew your food.

Apart from you mandible and your vomer, all your facial bones are arranged in pairs. That's why your face is symmetrical. For example, your two zygomatic bones form your cheekbones and the outside of your eye sockets on either side of your face.

From flexible to fixed joints

A human skull is almost full sized at birth. However the eight bones that make up the cranium are not yet fused together. This means that the skull can flex and deform during birth, making it easier to deliver a baby through the narrow birth canal. These individual plates of bone fuse together after about 24 months to form the adult skull.

The only bone in your skull that forms freely movable joints is your mandible, or jawbone.