Head and Neck Anatomy: Osteology of the Skull

How many bones are in the skull?

22

Suture

Joining of two or more bones

Foramen

Hole or opening in bone

Canal

tubelike opening through bone

How many bone are in the neurocranium?

8

What are the bones of the neurocranium?

Front bone, sphenoid bone, ethmoid bone, occipital bone, temporal bone, parietal bone

How many bones are in the viscerocranium?

14

What are the bones of the visceroncranium?

Mandible, vomer, nasal bones, lacrimal bones, zygomatic bones, palatine bones, maxillae.

Which bones of the viscerocranium are paired?

nasal bones, lacrimal bones, zygomatic bones, inferior nasal conchae, palatine bones, maxillae bones.

Which bones can you see in the anterior view of the skull (front of the skull)?

Frontal bone (eyes to the top of the skull), paired zygomatic and paired maxillae, nasal bones, small lacrimal bones, vertical nasal septum, inferior nasal conchae.

Which bones make up the orbit?

sphenoid, frontal, zygomatic, maxillae.

Which bone forms the superior orbital fissure?

Lesser and great wings of the sphenoid

Which bone forms the roof of the orbit?

The orbital plate of the frontal bone

Which bone forms the lateral wall of the orbit?

Primarily the zygomatic bone

Which bone forms the floor of orbit?

maxillae and some zygomatic bone

Which bones form the rim of the orbit?

Equal parts frontal, zygomatic, and maxillary bones.

Which bones can be seen in the lateral view of the skull?

Frontal, zygomatic, maxilla, mandible, nasal, lacrimal, ethmoid in the medial wall of the orbit, greater wing of sphenoid, temporal, parietal and occipital.

Which sutures can be seen in the later view of the skull?

Coronal, lambdoid and squamosal.

Which suture forms an inverted “v” and is only half visible on lateral view?

Lambdoid or parieto-occipital suture

Which suture is within the temporal fossa?

Squamosal suture

What are the 3 processes found on the lateral view of the skull?

Mastoid process, zygomatic process and styloid process

Where is the mastoid process?

projection on the temporal bone just behind the external auditory meatus.

Where is the zygomatic process?

It is part of the temporal bone and temporal process of zygomatic bone make up the zygomatic arch.

What is the function of the styloid process?

it is for the attachment of muscles and ligaments of the neck.

Which areas are seen in the inferior region of the skull?

Palatal region, posterolateral portion of the hard palate

What is seen in the palatal region of the inferior view of the skull?

Incisive foramen (think near incisors), median palatein suture (located in the middle of the palate), transverse palatine or palatomaxillary suture (creates a T with median palatine suture)

What is seen in the posterolateral portion of hard palate in the inferior view of the skull?

Greater palatine foramen, lesser palatine foramen, pterygoid hamuli or hamular process of medial pterygoid plate, lateral pterygoid plates and pterygoid fossa.

Which foramen or openings found in the inferior view of the skull?

Foramen ovale, foramen spinosum, carotid canals and foramen lacerum

Where is the foramen ovale?

It is in the sphenoid bone, transmits the fifth cranial nerve to the lower jaw

Where is the foramen spinosum?

It is found posterior to foramen oval, transmits middle meningeal artery.

What is the purpose of carotid canals?

openings for internal carotid arteries, posterior to foramen ovale and spinosum.

Where is the foramen lacerum?

Opening in floor of carotid canal, filled with cartilage.

What is the spheno-occiptial synchondrosis?

Junction of the sphenoid bone and occipital bone. It is the major area of endochondral bone growth, factor in development of malocclusion.

What makes up the opening for the facial nerve in the inferior view of the skull?

Stylomastoid faoramina, styloid processes, mastoid processes

Which view of the skull are you able to see the mandibular fossae of TMJ, articular eminence, jugular fossae (or foramina), occipital condyles?

Inferior view

What parts make up the ethmoid bone?

Crista galli, cribriform plate

What is the function of the crista galli?

serves as attachment for falx cerebri

What is the function of cribriform plate?

Passageway for olfactory nerve from nasal cavity to brain

Where is the greater and lesser wings of the sphenoid bone?

Behind the ethmoid bone

What is the function of the anterior cranial fossa?

Houses the frontal lobe of brain, anterior to the frontal bone