The only movable bone in the skull is the mandible, also known as the lower jawbone.
Understanding the Mandible's Unique Role
The human skull is composed of 22 bones (or 28 if you include the auditory ossicles). All of these bones, except for the mandible, are fused together, forming a rigid structure to protect the brain. The mandible, however, is uniquely articulated with the temporal bone via the temporomandibular joint (TMJ), allowing for a wide range of motion crucial for speaking, chewing, and facial expressions.
Several sources confirm this:
- BYJU'S: "[The mandible] or the jaw bone is one of the strongest and largest bones in the facial skeleton." https://byjus.com/biology/which-of-the-skull-bones-are-movable/
- Toppr: "The mandible, or jaw bone, is the only movable bone of the skull, forming the temporomandibular joint with the temporal bone." https://www.toppr.com/ask/question/which-of-the-skull-bones-are-movable/
- National Cancer Institute (NCI): "The mandible is the largest and strongest bone in the face. It forms the lower part of the jaw and part of the mouth. The mandible is the only moveable bone..." https://www.cancer.gov/publications/dictionaries/cancer-terms/def/mandible
- Lumen Learning: "The 22nd bone is the mandible (lower jaw), which is the only moveable bone of the skull." https://courses.lumenlearning.com/suny-ap1/chapter/the-skull/
The mandible's mobility is essential for various functions:
- Mastication (Chewing): The mandible's movement allows us to grind and crush food.
- Speech: Precise movements of the mandible are critical for clear articulation.
- Facial Expressions: The mandible contributes to a range of facial expressions.
