Skull · Irregular bone
Mandible (Lower Jaw)
The mandible is the lower jaw — the largest, strongest bone of the face and the only skull bone that moves. It holds the lower teeth and lets you chew, speak and open your mouth.
What it is
The mandible is the U-shaped lower jawbone. It hinges on the skull at the temporomandibular joints, just in front of the ears.
Where it is
The lower part of the face, forming the chin and the lower jaw.
What it does
Holds the lower teeth and enables chewing, biting, speech and mouth movements. It is the only movable bone of the skull.
Connections
Joints and connections
- Temporomandibular joints (with the skull, one on each side)
When things go wrong
Common injuries and conditions
- Mandible (jaw) fracture
- Temporomandibular joint (TMJ) disorders — jaw pain and clicking
- Dislocated jaw
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
The mandible is the only bone of the skull that moves, and the temporomandibular joint is one of the most frequently used joints in the body.
Answers
Mandible: frequently asked questions
What is the mandible?
The mandible is the lower jawbone — the largest and only movable bone of the face. It holds the lower teeth and lets you chew and speak.
What causes jaw joint pain?
Jaw pain and clicking often come from temporomandibular joint (TMJ) disorders, linked to teeth grinding, stress or joint strain. Persistent jaw pain is worth having assessed by a dentist or GP.
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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