Bones and cavities of the facial
cranium
TMJ
Anterior Skull
frontal bone
supraorbit
al
foramenbone
zygomatic
mandibul
ar
symphysis
mental
foramen
glabella
infraorbita
l foramen
maxillar
y bone
alveolar fossa
mandible
Anterior Skull
perpendicular
plate
superior
orbital fissure
inferior nasal
concha bone
nasal
bone
middle nasal
concha
vomer bone
Paranasal Sinuses
frontal sinus
ethmoid
sinus
maxilary sinus
sphenoid sinus
coronal suture
sagittal suture
lambdoidal
suture
Cranium
frontal bone
parietal bon
occipital bone
palatine process
palatine bone
vomer bone
temporal
bone
external occipital
protuberance
Ventral Skull
sphenoid bone
styloid process
mastoid proces
occipital bone
carotid
canal
jugular
foramen
foramen magnum
Occipital bone
occipital
condyle
squamosal
suture
lacrimal
bone
temporal
bone
external acoustic
meatus
mandibular
condyle
In mandibular
fossa
Lateral Skull
zygomatic arc
sphenoid
bone
sutural
bone
mastoid process
coronoi
d
process
styloid process
Lateral Skull
ramus angle body
mandible
cribriborm plate
crista galli
lesser wing
greater wing
optic canal
intenal
acoustic
meatus
sella turcica
ugular foramen
Internal Skull
Hyoid +
external
acoustic
meatus
Hyoid bone
temmporal
mandibular
joint
________
________
Sagittal
Coronal
Lambdoid
Squamous
Overview of Skull Geography
• Facial bones form the anterior aspect
• The cranial bones enclose the brain
Vault
• The cranial vault
or calvaria forms
the superior,
lateral, and
posterior aspects
of skull
• The cranial base
forming the
inferior aspect of
skull
Cranial Base
• Cranial base forms
the skull’s inferior
aspect
• Three prominent
ridges divide the
base into fossae
• The brain rests on
these cranial fossae
completely enclosed
by the cranial vault
• The brain occupies
the cranial cavity
Cranium
• The 8 cranial bones include; 2 parietal, 2 temporal
frontal, occipital, sphenoid, ethmoid
• Cranium is self- bracing allowing the bones to be
thin, yet strong
Occipital bone
• Forms most of the
posterior wall and
base of skull
• Articulates with
parietal &
temporal
• Joins w/ sphenoid
in the cranial floor
• Forms internal
walls of posterior
cranial fossa
Occipital bone - Int. landmarks
• Hypoglossal canal, Posterior cranial fossa
Temporal Bone
• Forms the inferolateral aspects of
the skull
• Parts of the
cranial floor
• Divided into four
regions;
squamous
tympanic,
mastoid, and
petrous-(int)
Temporal Bone
• The internal
petrous region
contributes to
the cranial base
• The petrous
region and the
sphenoid bone
form the middle
cranial fossa
Temporal Bone - landmarks
• Zygomatic
process
– Meets the
zygomatic
bone
– Forms the
cheek
• Mandibular
fossa
– Receives
condyle of
mandible
Temporal bones - landmarks
• Stylomastoid
foramen
– exit for facial
nerve
• Carotid canal
– entrance for
the carotid
artery which
supplies blood
to cerebral
hemispheres
Sphenoid bone
• Bone spanning the
width of middle
cranial fossa
• Articulates as
central wedge of all
cranial bones
• Consists of central
body and three
processes; greater
and lesser wings
and pterygoid
process (pos. view)
Sphenoid - landmarks
•
•
•
•
•
Sella turcica (enclosure for pituitary gland)
Optic foramina (passage of optic nerves)
Superior orbital fissure (Nerves III, IV, V enter orbit)
Foramen rotundum & ovale (Cranial Nerve V to face)
Foramen spinosum (Middle meningeal artery)
Ethmoid bone
• Forms most of
the area between
the nasal cavity &
orbits of eyes
• Lies between
nasal bones &
sphenoid
• Complex shape
gives rise to nasal
septum, sinuses
and cribiform
plate
Ethmoid bone - landmarks
• Cribiform plates
– Forms roof of nasal
cavity
• Olfactory formina
– Olfactory nerves
enter brain
• Crista galli
– Attachment of the
dura mater which
secures brain in
cavity
Facial bones
• Consists of 14
bones w/ only
mandible and
vomer unpaired
• Others include
maxillae,
lacrimals, nasals,
zygomatics,
inferior nasal
conchae, and
palatines (not
pictured)
Mandible
• Forms the lower
jaw
• Largest, strongest
bone of the face
• It has a body and
two upwardly
projecting
sections called
rami
• Houses lower
dentition
Mandible - landmarks
•
•
•
•
•
•
•
•
Mandibular angle
Mandibular notch
Coronoid process
Mandibular
condyle
Alveolar margin
Mandible formina
Mental formina
Ramus of mandible
Maxillary bone
• Forms upper jaw
and central
portion of facial
skeleton
• Fused medially
• Articulates with
all facial bones
except mandible
• Upper dentition
• Forms 2/3 of
hard palate of
the mouth
Zygomatic
process
Maxillary
bone
Maxillary bones - landmarks
• Alveolar margin
– Upper dentition
• Frontal process
– Forms lateral
aspects of nose
• Zygomatic
process
– Articulates with
zygomatic bone
• Maxillary sinuses
– (Fig. 7.11)
Palatine bones
• The horizontal
plates forms the
posterior portion
of hard palate
• Vertical plate
forms part of the
posterolateral
wall of nasal
cavity and a small
portion of orbit
Palatine bones - landmarks
• Horizontal plate
– Posterior section
of hard palate
• Vertical plate
– Part of the
posteriolateral
walls of nasal
cavity
• Orbital surface
– Part of inferior
medial aspect of
orbit
Vomer
• Forms part of
the nasal
septum
• Discussed with
the nasal cavity
Vomer - landmarks
• Plow shape
– Divides nasal
septum into
right and left
parts
Inferior Nasal Conchae - Landmark
• The Inferior
nasal conchae is
just one of
three in the
nasal cavity
• Superior and
middle concha
are on the
Ethmoid bone
The Orbits
Paranasal sinuses
• Note positioning
around nasal
cavity
Paranasal sinuses
•
•
•
•
Sphenoid sinus
Frontal sinus
Ethmoid sinus
Maxillary sinuses
Hyoid bone
• Body
– Neck muscle
attachment
• Greater horn
– Neck muscle
attachment
• Lesser horn
TMJ
TMJ Capsule
TMJ Capsule
TMJ Motions
TMJ Motions
The Skull: Fractures
• Egg Shell Fracture of
the Parietal bones.
• Results from a fall or
blunt force to the
head
The Skull: Fractures
• Another example of
an egg shell fracture.
Knife in Skull Above Orbit
AP Projection