Module 23: Skull and Muscles of the Face
Learning Objectives:
By the end of this module, students will be able to:
- List the cranial and facial bones of the skull and identify key anatomical features/landmarks.
- Name and describe/locate the sutures between cranial bones.
- Identify the various foramen of the skull and list what travels through them.
- Describe the major muscles involved in facial expression and their functions
Terms to Know
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Skull
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Muscles of Facial Expression
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*NOTE – Most of the reading about the cranial and facial bones is very in-depth. Remember – the learning objective is to list the bones and identify key features/landmarks (identified above for each bone).
The cranium (skull) is the skeletal structure of the head that supports the face and protects the brain. It is subdivided into the facial bones and cranial bones. The facial bones underlie the facial structures, form the nasal cavity, enclose the eyeballs, and support the teeth of the upper and lower jaws. The rounded cranium of the cranial bones surrounds and protects the brain and houses the middle and inner ear structures.
Anterior View of Skull
The anterior skull consists of the facial bones and provides the bony support for the eyes and structures of the face. This view of the skull is dominated by the openings of the orbits and the nasal cavity. Also seen are the upper and lower jaws, with their respective teeth.
The orbit is the bony socket that houses the eyeball and muscles that move the eyeball or open the upper eyelid. The upper margin of the anterior orbit is the supraorbital margin.
Inside the nasal area of the skull, the nasal cavity is divided into halves by the nasal septum. The upper portion of the nasal septum is formed by the perpendicular plate of the ethmoid bone and the lower portion is the vomer bone. Each side of the nasal cavity is triangular in shape, with a broad inferior space that narrows superiorly. The nasal concha (superior – part of the ethmoid, middle – part of the ethmoid, and inferior) are found in the nasal cavity.
Lateral View of Skull
A view of the lateral skull is dominated by the large, rounded cranium above and the upper and lower jaws with their teeth below. Separating these areas is the bridge of bone called the zygomatic arch. The zygomatic arch is the bony arch on the side of the skull that spans from the area of the cheek to just above the ear canal. It is formed by the junction of two bony processes: a short anterior component, the temporal process of the zygomatic bone (the cheekbone), and a longer posterior portion, the zygomatic process of the temporal bone, extending forward from the temporal bone.
Bones of the Cranium
*This content is covered in the pre-lecture assignment and is largely self-study. Parts will be addressed briefly in lecture.
The cranium contains and protects the brain. The interior space that is almost completely occupied by the brain is called the cranial cavity. This cavity is bounded superiorly