Download Paired bones

Skull
SHANDONG UNIVERSITY
Liu Zhiyu
Skull
The skull is
composed of 23
bones, which may be
divided into the
cerebral craniumand
facial cranium
Skull
Cerebral cranium
(8)
―larger, upper and posterior part,
contains and protects the brain
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Single bones: include
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frontal bone
ethmoid bone
sphenoid bone
occipital bone
Paired bones: include
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temporal bone
parietal bone
Skull
Bones of facial cranium (15)
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―smaller, lower, and anterior part,
contains bones that surrounded the
eye, nose and mouth
Single bones: include
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mandible
vomer
hyoid bone
Paired bones: include
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maxilla
nasal bone
lacrimal bone
palatine bone
zygomatic bone
inferior nasal concha
Bones of facial cranium
parietal bone
Frontal bone
Sphenoid bone
Temporal bone
Zygomatic bone
Nasal bone
Maxilla
Mandible
Occipital bone
Mandible
Body of mandible
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Superior border: alveolar arch
Inferior border: base of
mandible
Outer surface: mental
protuberance
Mental foramen
Inner surface: mental spine
Digastric fossa
Mandible
Ramus
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Mandibular notch
Coronoid process
Condylar process
 head of mandible
 neck of mandible
Mandibular foramen
Mandibular lingula
Angle of mandible
Masseteric tuberocity
The skull as a whole
Skull viewed from above (superior view)
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Bones:
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Sutures:
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frontal bone
paired parietal bone
occipital bone
Coronal suture
Sagittal suture
Lambdoid suture
parietal tuber
parietal foramen
Skull viewed from above (superior view)
Internal surface of the calvaria
 sulcus for superior sagittal sinus
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granular foveola
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arterial grooves
Skull viewed from behind
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External occipital
protuberance
Superior nuchal line
Inferior nuchal line
Internal view of base of skull
Base of skull forms three fossae
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Anterior cranial fossa
Middle cranial fossa
Posterior cranial fossa
Internal view of base of skull
Anterior cranial fossa
Formed by orbital part
of frontal bone,
cribriform plate of
ethmoid, and lesser
wings of sphenoid
Structures:
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frontal crest
foramen cecum
crista galli
cribriform plate
cribriform foramina
Meddle cranial fossa
Formed by the body and
greater wings of sphenoid,
petrous part of temporal
Structures:
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Body of sphenoid bone
Hypophysial fossa
Optic canal
Anterior clinoid process
Tuberculum sellae
Dorsum sellae
Posterior clinoid process
Sella turcica
Meddle cranial fossa
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Carotid sulcus
Superior orbital fissure
Foramen rotundum
Foramen ovale
Foramen spinosum
Sulcus for middle meningeal artery
Foramen lacerum
Internal opening of carotid canal
Trigeminal impression
Arcuate eminence
Tegmen tympani
Posterior cranial fossa
Formed by occipital and the petrous part of
temporal
Structures:
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foramen magnum
clivus
internal opening of hypoglossal canal
internal occipital protuberance
internal occipital crest
sulcus for transverse sinus
sulcus for sigmoid sinus
jugular foramen
internal acoustic pore
internal acoustic meatus
Skull viewed from below (inferior view)
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alveolar arch
bony palate
median palatine suture
incisive foramina
incisive canal
greater palatine foramen
posterior nasal apertures
pterygoid process
occipital condyle
external opening of hypoglossal canal
external opening of carotid canal
styloid process
stylomastoid foramen
mandibular fossa
articular tubercle
Lateral view of the skull
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External acoustic
pore
Mastoid process
Zygomatic arch
Temporal fossa
Pterion
Superior temporal line
Lateral view of the skull
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Infratemporal fossa
pterygomaxillary fissure
pterygopalatine fossa
sphenopalatine
foramen
Skull viewed from the front (anterior view)
Frontal region:
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frontal squama
frontal tuber
superciliary arch
glabella
Orbit
pyramid-shaped paired cavities
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Base: supraorbital notch
infraorbital foramen
Apex: optic canal
Walls
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Superior:
fossa for lacrimal gland
Medial:
fossa for lacrimal sac
Inferior:
infraorbital fissure
infraorbital groove
infraorbital canal
Bony nasal cavity
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Roof: cribriform plate of ethmoid
Floor: bony palate
Medial wall ― bony septum of nose
Lateral wall
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Superior, middle and inferior nasal conchae
Superior, middle and inferior nasal meatus
(underlying each concha)
Sphenoethmoidal recess
above superior nasal concha
Anterior ―piriform aperture
Posterior ―posterior nasal aperture
communicates with pharynx
Paranasal sinuses
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Frontal sinus
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Lies in frontal bone, deep to superciliary arch
Drain to anterior part of middle meatus
Paranasal sinuses
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Maxillary sinus
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Largest paired sinus, lie in the body of maxilla;
Opening into middle nasal meatus
Paranasal sinuses
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Ethmoidal cellules
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Lie in ethmoidal bone,
contains large number of
air cells, divided into
anterior, middle and
posterior groups
Anterior and middle
groups drain into middle
nasal meatus, while
posterior group drains
into superior nasal
meatus
Paranasal sinuses
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Sphenoidal sinus
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Lies in body of
sphenoid bone
Drain into
sphenoethmoidal
recess
General characters of the skull at birth
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The skull at birth is large in
proportion to rest of the
skeleton ―1/4 (adult 1/7)
The facial portion equals about
one eight that of the cranium in
size, whereas in adult it is one
half (1/4)
Many bones consist of more
than one piece
General characters of neonatal skull
Cranial frontanelles
―unossified membrane
between the bones at the
angles of parietal
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Anterior frontanelle
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Posterior frontanelle
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Mastoid fontanelle
Sphenoidal fontanelle
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―closes during middle of 2nd
year
―closes by the end of 2nd
month after birth
Anteroposterior radiograph of skull.
Lateral radiograph of skull.
Horizontal CT at level of upper part of ramus of mandible
showing relationships of the pterygoid plates.