Skull & Facial Bones Flashcards
Name the cranial & facial bones, including which are paired and which are singular.
8 cranial bones: (4 singular) - frontal - sphenoid - ethmoid (can be considered both a cranial and facial bone) - occipital
(2 paired)
- parietal
- temporal
14 facial bones:
(2 singular)
- vomer
- mandible
(6 paired)
- maxillae
- zygomatic
- lacrimal
- nasal
- inferior nasal conchae
- ethmoid
Name the 4 major sutures of the skull:
Coronal:
between frontal and parietal bones
Sagittal:
between parietal bones
Lamboidal:
between occiput and parietal bones
Temporal / squamous:
Between temporal, occipital and parietal bones
How many cranial bones are pneumatized and which ones are they?
5 are pneumatized (contain sinuses): Frontal Temporal (x 2) Sphenoid Ethmoid
Define the Pterion and Asterion
Pterion:
(temple)
between sphenoid, temporal, frontal & parietal bones
Asterion
(star shaped)
between parietal, temporal and occipital bones
Define Lambda and Bregma
Lambda:
junction of sagittal and lamboidal sutures (between parietal & occipital bones)
Bregma:
junction of coronal and sagittal sutures (between frontal & parietal bones)
Name the 6 features of the frontal bone & describe:
Supraorbital margin: ridge around top of orbital sockets
Supraorbital foramen / notch: on supraorbital ridge, for passage of supraorbital nerve & vessels
Supraciliary arches: deep to eyebrows and superior to supraorbital margin. Extends laterally from glabella.
Glabella: meeting point between supraciliary arches superior to root of nose. Most anterior projection of forehead.
Zygomatic process: where frontal bone joints with zygomatic at lateral edge of supraorbital margin
Frontal sinuses
Name the 3 features of the zygomatic bone and describe:
Frontal process: meeting point with frontal bone, at lateral edge of supraorbital margin
Temporal process: meeting point with temporal bone laterally
Zygomatic arch: contributes to zygomatic arch with temporal bone (= cheekbone)
Name the 6 features of the maxillae bones and describe:
Maxillae bones form upper jaw & most of piriform aperture
Zygomatic process: where zygomatic & maxillae bones meet
Frontal process: where maxillae & frontal bones meet (at superior piriform aperture)
Infra-orbital foramen - inferior to each orbit, for passage of infra-orbital nerves and vessels
Intermaxillary suture - unites the 2 maxillae bones in midline of the face. runs between teeth inferiorly and piriform aperture superiorly.
Alveolar Processes - tooth sockets (alveoli)
Maxillary sinuses
Name the 8 features of the mandible & describe
Body: horizontal aspect
Rami: vertical aspects (right and left)
Mental protruberance -prominence of chin
Mandibular condyle - posterior projection on rami, forms TMJ with articular fossa of temporal bone
Coronoid process - anterior projection on rami
Mental foramina - inferior to 2nd premolar teeth, for passage of mental nerves & vessels
Mandibular symphisis - osseous union where 2 halves of the infantile mandible fuse
Alveolar processes - support mandibular (bottom) teeth
Which 6 bones make up the bony orbit?
Frontal (superior) Zygomatic (lateral) Maxilla (infero-medial) Lacrimal (medial) Ethmoid (medial) Sphenoid (posterior)
Name the 4 boundaries of the bony orbit
Superior - frontal
Inferior - maxillae
Lateral - zygomatic (superficial) & sphenoid (deep)
Medial - Lacrimal (superficial) & ethmoid (deep)
What is the pifirorm aperture?
An anterior opening in the facial bones (nasal cavity).
Vomer & nasal septum divide aperture into 2 bilateral chambers.
Formed by: Nasal bones (superior) Maxillae bones (lateral and inferior) Ethmoid bone (interior - middle nasal conchae) Inferior nasal conchae (interior & inferior) Vomer bone (interior & inferior)
What are the 6 features of the temporal bone?
Temporal fossa (crosses to parietal, frontal & sphenoid bones) - bounded by superior & inferior temporal lines superiorly, & temporal arch inferiorly)
Zygomatic process -m eeting point with zygomatic bone laterally
Mastoid process - large round process behind ear on postero-lateral aspect of bone
Styloid process -slender process posterior to mastoid process on postero-lateral aspect of bone
Styloid mastoiod foramen - between mastoid & styloid processes
External acoustic meatus opening
What are the 6 features of the occipital bone?
EOP / Inion
3 x lines running laterally from EOP:
Highest nuchal line
Superior nuchal line
Inferior nuchal line
External occipital crest - descends from EOP toward foramen magnum
Foramen magnum - large circular opening in basal part of occipital bone, for passage of spinal cord & meninges, vertebral arteries, posterior & anterior spinal arteries, and CN XI spinal accessory nerve
What are the 4 main areas of the sphenoid?
Body
Greater wings
Lesser wings
Pterygoid processes
