Skull Flashcards
The cranium is formed by how many bones?
22
The neurocranium consists of the dome-shaped ___ (skullcap) and the basal plate called ___.
calvaria; basicranium
Viscerocranium is formed from the skeleton of the ___ ___
pharyngeal arches
The neurocranium is mainly derived from ossified ___ from the neural crest
mesenchyme
Skull bones are mostly formed through ____ ossification
membranous
Bones forming the calvaria consist of the outer layers of dense bone with the spongy bone sandwiched in between the dense cortical bone. The spongy bone is known as what? What does it contain?
diploe; contains large venous channels that communicate with veins of the scalp and venous channels inside the skull
The bones of the skull are connected by fibrous interlocking ___ but during childhood some basicranial bones such as occipital and sphenoid are connected by ____
sutures; cartilage
This is the point on the cranium where frontonasal and internasal sutures meet
naison
This is a smooth prominence most marked in males; on frontal bones superior to root of nose between eyebrows
glabella
this is the point on calvaria at the junction of coronal and sagittal sutures
bregma
this is the superior point of neurocranium, in middle with cranium oriented in anatomical plane
vertex
this is the point on calvaria at junction of lambdoid and sagittal sutures
lambda
this is the junction of greater wing of sphenoid, squamous temporal, frontal, and parietal bones
pterion
this is star-shaped; located at junction of three sutures: pariestomastoid, occipitomastoid, and lambdoid
asterion
this is the most prominent point of external occipital protuberance
inion
_____ are “soft spots” on head present in neonates and are clinically important
fontanelles
The large flat squamous part of this bone forms the skeleton of the forehead
frontal bone
____ form the upper jaw. The two bones are united at the inter maxillary suture
maxillae
These bones (both sides) form the prominence of the cheeks and articulate superiorly with the frontal bones, inferiorly with the maxillae, and posteriorly with the zygomatic process of the temporal bone
zygomatic bones
The orbital part of the ___ bone forms the roof of the orbit. The orbital process of the ___ bone forms the floor of the orbit.
frontal; maxillary
Maxillae form most of the ____ aperture, which serves as an opening for the nasal cavity. The aperture is divided into two halves by the ___ ___.
piriform; nasal septum
The nasal septum is formed by the ___ ___ of the maxillae
nasal crests
On the lateral side of the nasal cavity are curved bony plates called what?
nasal conchae
The maxillary sinus is a large pyramid-shaped space in the maxillary bone that drains into the ___ ___ of the nose
middle meatus
___ bones form the superior border of the piriform aperture
nasal
___ bones form the medial wall of the orbit
lacrimal
The alveolar process on the body of the mandible contains the mandibular ____
teeth
In regards to the body of the mandible, the mental foramina for the mental nerves and vessels are located inferior to what?
the second premolar teeth
The rams of the mandible (vertical part) has two processes, the condylar and coronoid separated by the ___ ___. Below this on the medial side of the ramus is the mandibular foramen which leads into the mandibular canal that contains the ___ ___ nerve.
mandibular notch; inferior alveolar
The ___ process forms the condyle for the articulation with the temporal bone through the TMJ
condylar
The ____ process serves for the attachment of the temporalis muscle
coronoid
The medial wall of the orbit is formed by 4 bones. What are they?
orbital plate of ethmoid bone, frontal process of maxilla, lacrimal, and sphenoid bones
The lateral wall of the orbit is formed anteriorly by the ____ bone and posteriorly by the ____ bone
zygomatic; sphenoid
This is a horizontal fracture of the maxillae, passing superior to the maxillary alveolar process, crossing the bony nasal septum
Le Fort I
This fracture passes obliquely from the posterolateral parts of the maxillary sinuses superomedially through the infra-orbital foramina, lacrimals, or ethmoids to the bridge of the nose.
Le Fort 2
note: as a result, the entire central part of the face, including the hard palate and alveolar processes, is separated from the rest of the cranium
This is a horizontal fracture that passes through the orbit and the nasal bones and extends laterally though the greater wings of the sphenoid and the frontozygomatic sutures
Le Fort III
note: concurrent fracturing of the zygomatic arches causes the maxillae and zygomatic bones to separate from the rest of the cranium
In the lateral view, the calvaria are formed by the ___, ___, and ___ bones
frontal; parietal; and occipital
The frontal bone articulates with the parietal bones through the ___ suture
coronal
The parietal bones articulate with each other through the ___ suture, whose junction with the coronal suture is the ____
sagittal; bregma
Parietal bones articulate with the occipital bone though the ____ suture, whose junction with the sagittal suture is the ____
lambdoid; lambda
In regards to the temporal bone, the ___ process projects laterally and anteriorly. It articulates with the zygomatic bone to form the zygomatic arch
zygomatic
In regards to the temporal bone, this part forms the external acoustic meatus, which opens laterally
tympanic part
In regards to the temporal bone, this part forms a large ventral projection, the mastoid process, which serves for the attachment of important musculature including the sternocleidomastoid muscle
mastoid part
In regards to the temporal bone, this sharp needle-like ventral projection serves for the attachment of musculature and ligaments
styloid process
The scams part of the occipital bone forms most of the ____
ociput
The junction of the coronal and sagittal sutures is the ___
bregma
The ___ ___ is formed by the palatine process of the maxillae anteriorly and the horizontal plates of the palatine bones posteriorly. Its posterior boundary is formed by the ___, or the posterior nasal apertures
hard palate; choanae
The incisive foramina are located in the incisive fossa and allow communication between what?
the hard palate and nasal cavity
The greater and lesser palatine foramina allow for the passage of what?
the descending palatine artery and vein and greater and lesser palatine nerves into the oral cavity
This bone forms the posteroinferior aspect of the bony nasal septum
vomer
This bone is an irregular, unpaired bone that consists of a body and three pairs of processes: greater wings, lesser wings, and ptrerygoid processes.
sphenoid
In regards to the sphenoid, this is large and found posteriolateral to the ptyerygoid process. Its for the passage of CN V3 (mandibular nerve), lesser petrosal nerve, and accessory meningeal artery
Foramen ovale
In regards to the sphenoid, this is found posteriolateral to the f. ovale and serves as the passage for the MMA
foramen spinosum
The petrous part of the temporal bone is wedged between the ___ and ___ bones
sphenoid; occipital
note: at the medial point of junction of these three bones is an irregular opening, which in life is filled with cartilage, called foramen lacerum
The groove for the cartilaginous part of the pharyngotympanic (auditory) tube lies between what?
the sphenoid and petrous part of the temporal bone
this is a notch between the petrous portion and the basilar part of the occipital. Cranial nerves CN IX, CN X, CN XI, as well as the internal jugular vein pass through it
jugular foramen
The mandibular fossa is located within the ventral part of the ___ portion of the temporal bone
squamos
This is located posterior to the base of the styloid process and allows for the passage of the facial nerve and sylomastoid artery
sylomastoid foramen
The most prominent feature of the occipital bone is the ___ ___, which is the largest foramen in the skull, for spinal cord with accompanying structures
foramen magnum
This part of the occipital bone forms the anterior border of the formate magnum
basilar part
The lateral parts of the occipital bone form prominent occipital condyles for articulation with the ___
atlas
