Skull · Flat bone
Cranium (Skull)
The cranium is the skull — the set of bones that surround and protect the brain and form the face. The adult skull has 22 bones, most fused firmly together, with the jaw being the only one that moves.
What it is
The skull is a complex structure of 22 bones: eight form the cranial vault (the dome protecting the brain) and fourteen form the face. All but the lower jaw are locked together at immovable joints called sutures.
Where it is
The head, enclosing the brain and forming the framework of the face.
What it does
Protects the brain, houses and protects the organs of sight, hearing, smell and taste, forms the face, and provides the framework for chewing and speech.
Connections
Joints and connections
- Sutures (immovable joints between skull bones)
- Temporomandibular joint (with the lower jaw)
- Joint with the top of the spine
When things go wrong
Common injuries and conditions
- Skull fracture (from significant head injury)
- The soft spots (fontanelles) in babies allow the skull to grow
Education and reference only. This explains the anatomy in plain terms; it is not a diagnosis. A severe injury, a visibly deformed limb, or the inability to move or bear weight needs urgent assessment — call 999 or go to A&E for a serious injury.
Did you know?
An interesting fact
A newborn's skull bones are not yet fused, leaving soft spots (fontanelles) that let the head pass through the birth canal and allow the brain to grow rapidly.
Answers
Cranium: frequently asked questions
How many bones are in the skull?
The adult skull has 22 bones — 8 forming the cranial vault around the brain and 14 forming the face. Only the lower jaw moves; the rest are fused.
Why do babies have a soft spot?
A baby's skull bones are not yet fused, leaving soft spots (fontanelles). These let the head pass through the birth canal and allow the brain to grow, and they close over the first couple of years.
Explore the skull
Related bones
Sources
Where this is drawn from
- NHS — Anatomy and body systems
- Gray's Anatomy for Students (Drake, Vogl, Mitchell)
- TeachMeAnatomy — skeletal system
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