Prac 2: Anatomy of External Skull Flashcards
Excluding the 32 teeth and 6 auditory ossicles, how many bones are in the skull?
22
What types of joints exist between bones of the skull?
All fibrous (sutures) -> which ossify in adults over a variable amount of time
Aside from auditory ossicles, the only non-fibrous joint is the Temporomandibular Joint (TMJ) = Bilateral synovial hinge
What portion is the neurocranium?
The portion surrounding the brain - more dorsal
What portion is the facial skeleton?
Anterior and lower portions of the skull
List the facial bones. Which ones aren’t paired?
Mandible (unpaired) Vomer (unpaired) Maxilla (2) Zygomatic (2) Lacrimal (2) Nasal (2) Inferior Nasal Concha (2) Palatine (2)
Bones of the neurocranium are?
Frontal, Occipital, Parietal (2), Temporal (2), Sphenoid and Ethmoid
What are the two divisions of the neurocranium?
Calvaria (skull cap)
Cranial Base: Cranial base further divided into Anterior, Middle and Posterior Fossae
Coronal suture - between which bones?
Frontal and Parietal
Lambdoid Suture?
Parietal and Occipital
Sagittal Suture?
Between the 2 parietal bones
Squamosal Suture?
Arches posteriorly from the pterion, from the temporal squama to the lower border of parietal bone
What is the Lambda?
Meeting of the sagittal and lambdoid sutures
thus meeting of the two parietal bones and occipittal bone, posteriorly
What is the Bregma?
Meeting of the Sagittal and Coronal sutures
thus of frontal bone and parietal bones
What is the vertex?
Highest point of the skull
Formed by 4 bones: Frontal, 2 parietals and the occipital
What is the Pterion?
Short suture on the lateral side of the skull where the greater wing of the sphenoid articulates with 3 other bones:
- Temporal (squamous part)
- Frontal
- Parietal
What is the asterion?
At the articulations of the Parietal, Occipital and Temporal Bones - posterolaterally
What is the nasion?
Meeting of the nasal and frontal bones
What is the inion?
The most prominent part of the external occipital protuberance
What are the articulating portions involved in the TMJ?
The head of the condylar proces of mandible
with
Mandibular fossa of temporal bone
By what type of joint are the teeth attached to the mandible and maxilla?
Gomphoses - fibrous peg-in-socket joints
From teeth to the inferior (mandible) and superior (maxilla) alveolar processes
Where is the mandibular foramen located? Where does it lead?
Medial aspect of the ramus of mandible
Leads into mandibular canal
Which nerves and blood vessels are transmitted in the mandibular canal?
Inferior Alveolar Nerve (from V3)
Inferior Alveolar Artery and Vein
Where is the mental foramen located?
What emerges from here?
Anterolateral aspect of the mandible
Mental nerve and blood vessels (from the mental canal)
What is the superior nuchal line?
Extends laterally from the external occipital protuberance
What muscle attaches to the mastoid process of the temporal bone?
The sternocleinomastoid
Where is the mastoid notch? Which muscle attaches here?
Just medial to the mastoid process
Posterior belly of digastric muscle attaches here
What are the two parts of the zygomatic bone? With which bones do they articulate?
Frontal Process (superiorly) -> with fronal bone Temporal process (posteriorly) -> with temporal bones