The jaw is composed of two main bones: the lower jaw, known as the mandible, and the upper jaw, known as the maxilla.
These two parts work together to allow for essential functions like chewing, speaking, and breathing.
The Lower Jaw (Mandible)
The lower jaw, or mandible, is a single bone forming the bottom part of the jawline. It is unique among the skull bones because it is mobile.
- Key Functions and Features (According to the reference):
- Supports the bottom row of teeth.
- Gives shape to the lower face and chin.
- This is the bone that moves as the mouth opens and closes.
This mobility is crucial for mastication (chewing) and articulation (speaking).
The Upper Jaw (Maxilla)
The upper jaw, or maxilla, is actually a pair of bones fused together to form the roof of the mouth and the floor of the nasal cavity. Unlike the mandible, the maxilla is fixed and does not move independently.
- Key Functions and Features (According to the reference):
- Holds the upper teeth.
- Shapes the middle of the face.
- Supports the nose.
Together, the mandible and maxilla form the framework for the mouth and contribute significantly to the structure of the face.
Summary Table: Jaw Components
For clarity, here's a simple breakdown of the two main jaw bones:
| Component | Scientific Name | Mobility | Supports | Shapes |
|---|---|---|---|---|
| Lower Jaw | Mandible | Mobile | Bottom row of teeth | Lower face and chin |
| Upper Jaw | Maxilla | Fixed | Upper teeth & the nose | Middle of the face |
Understanding the distinction between the mandible and the maxilla provides a complete answer to what the jaw is called. Both terms refer to parts of the jaw structure.
