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Anatomy Made
Easy “MSS”
part #: 2
‫هذا الجزء بيشمل التفريغ الثالث والرابع‬
Done By :Ruba Rababah
Edited by: Awn Academic team
Good luck Awn 
Subjects of this Lecture:
Temporal Bone
 Occipital Bone
 Sphenoid Bone
 Ethmoid Bone
Facial bones
 Nasal cavity
 Orbit
Hyoid Bone

Temporal Bone
Forms the infero-lateral aspect of
the skull and part of the cranial
floor.
Articulate with the parietal bones by
Squamous suture.
New
**In temporal bone we have 2 lines called
temporal lines  one of them
is superior and the other is inferior.
Practically, the superior one is located more
posterior & the other one is
anterior-inferior , they are very important for
the origin of temporalis muscle.
**Although we call them temporal lines or
ridges but one of them is located
or jointly located at the level of the parietal
bone.
Temporal Bone
Consists of four parts:
Squamous part
Mastoid part
Petrous part
Tympanic part
two parts can
be seen from
the lateral
view of the
skull which
are: the
squamous
and mastoid
parts
1-Squamous part
 Very
smooth and flat
 A rticulate with the parietal bone by
Squamous suture (superiorly and posteriorly)
 and with the greater wing of the
sphenoid bone by the
sphenotemporal suture (anteriorly)
P
S
T
Zygomatic Process:

New
inferior to the squamas part of the temporal bone,
zygomatic processprojects all the way anteriorly
from thePosterior aspect of temporal
bone.
Articulate with theTemporal process of the zygomatic bone
forming >>The ZygomaticA rch
Pay attention that the temporal
process is longer than the zygomatic
process.
New
** in zygomatic process we have 2 borders:
1- complete lateral surface
2-incomplete medial surface.
* The inferior border has a ridge or
elevation called mandibular elevation, it
provides insertion for the ligaments that
contribute in forming the tempor-mandibular
joint.
2-Mastoid Part
Seen in the lateral view of the skull.
Located in the posterior-inferior aspect.
Contains :Mastoid & styloid process.
Both process are there as origin for neck
muscles that go to hyoid or mandible bone.
**Mastoid process: ( spongy in shape)
empty bone filled with air cells ( mastoid air
cells) ,located posterior inferior to the
external auditory meatus .
Make balance in 2 ways :
sustaining the head in it’s position. ‫بخفف وزن‬
‫راسك‬
 vibration of the voice (to hear your sound)
and improve (increase) the resonance and echo of
the sound
**They also make the bone light
**they have no connection with the outside.
New
**Styloid process :(pin-sharp) located inferior to external
auditory meatus (which is anterior to mastoid process) ,
and anterior to the mastoid process.
‫كيف تتذكرها ؟ الستايلود ما بتقدر تحسه النه جاي قدام الماستويد الي بتقدر تحسه‬
**it provides the attachment for the muscles that goes to the
neck & some of them to the pharynx and mandible. E.g..
stylohyoid / stylomandibular / stylopharyngeal
‫ راح تكيف عليهم الحقا بجيهم وقتهم‬, ‫ال تحفظهم هال عادي‬
**The external auditory meatus is surrounded anteriorly &
superiorly by what we call auditory or the tympanic rich.
**anterior to the external auditory meatus we have a
small depression called the mandibular fossa.
Petrous part
Triangular in shape like a pyramid
_Can’t be seen laterally,Instead it can be seen from:
** Superior view (by removing the vault of the skull)
- in this view the essential organs of hearing (
middle & inner ear) can be seen in the interior
portion of the petrous part.In addition to the
Internal acoustic (auditory) meatus for the
facial nerve and other structures.
Petrous portion articulates with the Lateral aspect of
the body of sphenoid bone and articulates with the
anterior arch of the foramen magnum (which is
part of the occiptal bone).
**Inferior view of the skull
New
**M idsagittal section of the skull:
it appears in this view triangular in shape with a
superior border,anterior surface and posterior
surface.
The anterior one is flat so it has nothing on it,
whereas the posterior one has 2 openings; the
internal acoustic meatus you can see it from the
superior view only and the external acoustic meatus
you can see it from lateral view.
The end of petrousal part is lacerated; it is irregular & it
contributes to form an opening which is the foramen
lacerum. (In order for you to identify where is the foramen lecarum you have
to go to the tip of the petrousal part of temporal bone.)
New
Questions that where mintioned by the Dr that might come in the
exam… [ check next slide for image ]
* the tip of the petrousal part of temporal bone is
share with the sphenoid bone..HOW ?
by foramen lacerum.
‫ عظام‬3 ‫اصال هاي الفتحة مشتركة بين‬
temporal , sphenoid , occipital
* the part which is occupied anteriorly by the body of sphenoid,
posteriorly by the nuchal line and laterally by posterior surfaces of
petrousal part is called … ???
Posterior cranial fossa.
Petrousal part of the temporal bone and the sphenoid bone  foramen lacerum.
Petrousal oart of the temporal bone and the occipital bone  jugular foramen.
Temporomandibular Joint TMJ
At the level of the petrous portion
It is a synovial joint with a fibrous disk
between the base of the skull and the
mandible;where the head –condyle- of
the mandible fits in the mandibular
fossa.
The joint is maintained in its position by:
Masticatory muscles and the Masseter
muscles -which is the most powerful
muscle that can cut person’s finger-
Temporomandibular Joint TMJ
This joint is very important for movements of
Mandible including:
Protrusion:forward movement
Retrusion :backward movement
Circumduction:slight movement of
rotation
* this movement occurs in all joints with a
disk in between
Occipital Bone
L-shaped bone;similar to the frontal
bone but with a different orientation of the
L-shape:in the frontal it is posterior
while in occipital it is anterior.
The lateral aspect of the L-shape limb of
the occipital bone articulate Laterally
with the petrous part of the temporal
bone whereas anteriorly it will
articulate with the posterior aspect of
the sphenoid bone.
New
**The small limb can be seen from posterior view, the other
part which is the long limb (low horizontal limb) can be seen
more clearly from superior & inferior views of skull.
** In occipital bone there are 2 lines, important for insertion of
posterior neck muscles, they are very important in moving the
head and enforcing the occipito-atlanto & atlanto-axial joints.
**occipital bone connects to the parietal bone through
lambdoid suture(the smaller-vertical limb with parietal),
whereas the inferior-anterior part is
connected by occipitomastoid suture with the mastoid portion
of temporal bone.
Occipital Bone; Posterior view
You can see :
_External occipital protuberance:elevation
in the midsagittal line.
It is at the meeting of superior & inferior nuchal lines
very important for palpation
_The Lambdoid suture.
_The superior and inferior nuchal lines ,the superior
is more important ,the inferior one is for the deep aspect
muscle origin of the neck. (you can palpate the superior nuchal
line, but the other line is more inferior and anterior.)
New
External occipital protuberance
if you go back in your head & press more posterior you
will see very smooth areas in the right & left sides of the
midline and in the midline you will see an elevation
called external occipital proturberance.
External occipital crest
The superior nuchal line is immediately in the same line
with occipital proturberane where the crest join the 2
lines.
The 2 lines connecting from left & right in the midline and
going all the way inferior & anterior forming the external
occipital crest which is an elevation.
**This crest ends in an opening called foramen
magnum
Occipital Bone; Superior view
 Foramen
Magnum :an opening through
which the medulla oblongate,brain stem,
spinal cord,and midbrain will pass.
 [ High yield point ]Lateral to this
foramen there are two openings
which are the Hypoglossal canals
through which the hypoglossal
nerve passes.
Also you can see grooves (indentations) for
venous drainage >> drain blood from the
New
lateral & anterior to this foramen there are 2 articular
processes called occipital condyle, they articulate with the
first cervical vertebra which is atlas, usually these condyles
are different in shape depending on the atlas, age of a
person, and the maturation of them.
**Anterior to the condyle the magnum is complete and
there is an important process called pharyngeal process,
practically it is the beginning of raphe which act as origin
and insertion for pharangyal muscles
New
. in this area we have the superior, middle and the inferior
pharyngeal muscles, these muscles make the lateral &
medial walls of the pharynx, so pharynx is not an organ, it
is a muscular organ.
** So the raphe of the upper part of that connection will
originate in pharyngeal tubercle
- somehow it’s similar to linea alpa is an aponeurosis which
is a fusion of the external, internal & transverse muscles in
the middle line
Repeated from previous lec
There are portions of the frontal bone
that make the roof of the eye,underneath
them we have the eye,between these
portions we have a protrusion of the ethmoid
bone (crista galli )
lateral to crista galli there is the cribriform
plate where the; perpendicular plate
(forms the superior portion of the nasal
septum).
Sphenoid Bone
The key stone (elements) in the skull; articulates with all other
cranial bones and keep the skull integral. (if you take it out, every
thing will fall apart)
From the anterior or posterior view; sphenoid appears as a
butterfly or bat shaped that spans the width of the middle
cranial fossa ,having :
Two ears: represent the lesser wings
Two wings :represent the greater wings
Body located in the middle;it is empty; thus called sphenoid
sinus >> it opens into the nose.
Two Legs: represent the pterygoid processes ( medial
&Lateral): project from the inferior part of the sphenoid bone
they provide insertion for the muscles of the larynx and
pharyngeal muscles (especially the superior & middle constrictor
muscle);
**between the lateral and medial processes, there is pterygoid
fossa which has lots of innervations.
Major markings :
Sphenoid bone –Superior view
You can see only Body,greater and Lesser
wings.
the body of the sphenoid is indented;these
indentations are called Sella turcica ,with t:two
limitations :
*anterior limitation >> tuberculum sellae)
*posterior limitations >>(dorsum sellae) the
dorsum sellae ends laterally by 2 processes, one on the left
and one on the right and these are called the clinoid
processes, they are very important in the pharynx.
* we have posterior and anterior clinoid process;
The anterior clinoid process is at the medial end of the border of the
lesser wing of sphenoid .
New
**Sella is a small wall that hosts or covers the anterior &
posterior aspect of the sella turcica. The sella in this
manner is a portion of this bone that is elevated like a crest
but it is not, it is shorter and thicker than the crest.
**The lesser wing of the sphenoid is more anterior and
superior ( and is lateral to the body) rather if you compare it
with the greater (bigger) wing of the sphenoid.
There is the groove for the middle meningeal artery
which is a dangerous area in the lateral trauma of the
head.
In the superior aspect of the skull:
You can see that Sella turcica Contains a depression, this
Depression is different from one person to another in shape,
depth & width and it is measured according to certain
measurement, it could be ovale,rounded .. and so on . It is
called “Hypophysial fossa”. Avimportant endocrine gland resides
in it that is called “Hypophysis pitutary gland” .
Lateral to the sella turcica there are the wings:
Lesser wings:small,articulate with the posterior aspect of the
frontal bone limb which is very thin.
G reater wings:deeper & wider and contain 3
important foramen >>>
Foramen of the greater wing of
sphenoid bone: (medially)
they are oriented from anterior to
posterior,toward the lateral
aspect (respectively( : ( ROS )
o foramen rotundum(most
anteriorly(
o foramen ovale
o foramen spinosum(spine in shape,
longest)
In the superior view of the skull you can
notice these structures:
A foramen called (foramen lacerum) it’s bordered
by the anterior part of the temporal bone (petrous part)
and the sphenoid.
Another foramens situated at the level of the base
of the lesser wings called ( the optic foramens),they
are the point of ligation between the lesser wings and
the body of the sphenoid.
**the optic foramen communicates the
middle cranial fossa with the eyes, and you can
see it only from superior view.
High yield point
- Inferior orbital fissure :
* Seen only from ant
* Part of maxillary bone
- superior orbital fissure :
* seen from ant & post
* part of sphenoid bone ( greater wing )
- the lesser wing contain the optic Canal
New
Foramen lacerum :
located within the greater wing of the sphenoid. So,
the greater wing of sphenoid & the lateral posterior
portion of the body of the sphenoid & the tip of
petrous part of the temporal bone will meet in one
point deficit way and they will leave an opening
Lacerated opening called foramen lacerum..
Sphenoid bone – inferior view of
the skull :
 only the inferior
portion of the
greater wing of the sphenoid,and
the two pterygoid processes will
be shown
 The
inferior portion of the sphenoid
body can’t be seen from the inferior
aspect, instead we’ll see the vomer
(part of the nasal septumwhich articulates with the anterio-inferior
aspect of the sphenoid.)
New
**Clinically:
Sometimes patient come to you and say that he is
hearing his pulsation from his ear while he is at silent
space region or sitting down with himself at night!! …
why??
 The carotid canal hosting the carotid artery ( it is
big artery) and the pulsation of the heart is
transmitted through it into the brain, and this canal
has a relationship with the internal ear, so you hear
the pulse.   
Important structures to be seen in
the inferior view of the skull:
the limb of the L of the occipital bone contains two
condyles (occipital condyles :they articulate with the
two masses of the atlas bone (the first vertebra).
 carotid canal and the jugular foramen,which are
located behind each other:located more posteriorly
in the skull just anterior and lateral to foramen
magnum (petrousal part of the temporal bone and the
carotid canal within it.)
 Foramen magnum.

Lateral to the occipital condyles we have 2 openings they
are shared depressions completed by the third part of the
temporal (petrousal part), these are the jugular foramen
through which the jugular vein passes into the neck
New
The lesser wing of the sphenoid bone articulates with the
horizontal plate of the frontal bone and a portion of the ethmoid
bone forming the anterior cranial fossa.
**posterior border of this fossa you will see the posterior border
of lesser wing of sphenoid but you don't see the frontal bone.
So.. we have anterior &
posterior cranial fossa but in
the middle of cranium because
we have the body of the
sphenoid bone & it is huge
elevated superiorly; we have 2
middle cranial fossa in which
the temporal loop of the brain
resi frontal loop, and we have
cerebellum.
in neonatal skull there is a lack of
fusion in frontal bone, it is a matter
of overlapping of these bones so
that will ease the birth process.
** u can see an incomplete
continue in frontal bone, Because
we have some parts of ethmoid
bone that protrude within the
anterior cranial fossa.
New
 the anterior cranial fossa is communicated
with nose through olfactory foramina;
** although it is not a real connection, but
the olfactory foramina allow the nerves that come
from the mucosa that covers the superior aspect
of the nose to pass through them into the pulp.
 The pulp will form a tract called olfactory tract
that will go all the way to the anterior aspect
of the medial side of the greater wing.
pharyngeal tubercle :

an elevation of the occipital bone to which a very
thin connective tissue rim goes all the way down and
provides the origin for the pharyngeal muscles
which are triangular in shape.

initiate what we call the common tendon of the
pharyngeal muscle (superior ,middle and
inferior constrictor muscles) .

It is very important and it’s there only to initiate the
origin of the pharyngeal muscles that will go anteriorly
so the superior constrictor will ligate to the medial
plate of the pterygoid process

(remember that the pterygoid processes will
provide insertion for the muscles).
Ethmoid bone
-‫شكلها مثل حرف التي‬ part of the nasal cavity,and part of the
facial bones.. But this is debatable.
 Forms
most of the bony area between the
nasal cavity and the orbits.
 It is the most
deep of the skull bones;it
lies between the sphenoid and nasal
bones.
It has a T- shape (2 parts a vertical and a
horizontal one),
 the vertical T part (you can see small part of it)
extends above within the cranial fossa giving us a
very sharp rim:Crista galli.;


Crista galli :(small part penetrates the horizontal plate)
located between the two very thin plates of the limb
of the frontal bone that makes the roof of the nose ).
There are 2 depressions lateral to crista galli
called olfactory bulp.

We can see part of the vertical plate when
we look at the anterior view of the skull.

In the lateral aspect of the horizontal plate there
are the lateral masses of the ethmoid bone
which have sinuses called ethmoid air sinuses
New
The lateral part of the horizontal plate is
called cribriform plate( perforated plate) ,
it has a lot of openings called olfactory
foramina ( foramena is the plural of
foramen).
Major markings :
plays a role in the
separation of the nasal
cavity (nasal septum).
Superoor view of the skull:
What we can see from the ethmoid bone ?
crista galli and the cribriform plates.
Facial bones “14 bones “
All the facial bones are paired bones except for the
Mandible and Vomer which are Unpaired.
Maxillary bone
Zygygomatic
Lacrimal
Nasal bones (the nasal septum divides the
cavity into two parts)
Palatines
Inferior chonchae
Mandible
Vomer
New
**The facial bone ligate with the cranium by :
1- Frontal process of the zygomatic bone and
zygomatic process of the frontal bone
2- Maxillary process of frontal bone and frontal
process of maxilla
3- Zygomatic process of the temporal bone and
temporal process of the zygomatic bone
(zygomatic arch)
****NOTE :the facial expression muscles don’t
pass joint and it give us the expression of our
face .
Maxillary bone
 The -facial keystone (main bone of the facial bones), located in the
middle of the face.
articulate with all other facial bones,except mandible
medially fused bones (2 fused bones) that make up the upper jaw ,the
openings of the naris and the central portion of the facial skeleton.
participates in forming the floor, border and walls of the orbit,part of
the lateral wall of the nasal cavity and in forming the floor of the
nose and the roof of the mouth.
New
The nasal opening (external nares) is made only by the medial border of the
maxilla which ends anterio-inferior by the nasal spine. Inferior to the spine
you can see the alveolar elevations which contains openings for teeth
embedded in it.
(when you put your fingers one in the nose the other in the mouth and press
against each other you’ll notice that it’s only one bone;the maxilla)
Maxillary bone :
 Has a huge body , frontal process of the maxilla
which will articulate with the frontal bone.
 Within this bone we have articular surface that articulates
with the zygoma,because of its small size some books call
it articular surface others call it a process >>
“Zygomatic process”.
(the maxilla has 4 processes two with frontal and another two with
zygomatic.)
 Has an anterior border which contains grooves which are
called alveolar processes,they represented by the teeth
which are imbedded in these alveoli.
( Posterior in this alveolar process there is rounded protrusion called tuberosity. )
 Major markings include: palatine,frontal and zygomatic
processes,the alveolar margins, inferior orbital
fissures and the maxillary sinuses.
New
In the posterior aspect of the body , inferior to zygomatic
process there is a line through this line there is a canal which is
called perforating posterior dental canal.
the palatine process of the maxilla and the palatine bone form
2 things: the floor of the nose and the roof of the mouth.
Inferior and anterior to the zygomatic process there is
depression called canine fossa.
The maxilla has two faces:
1-the superior face is oblique surface which is the orbital
surface seen only from the orbit.
2-the anterio-lateral surface is smooth surface.
New
This is the inferior view, you can see the palatine process of
the maxilla almost separated by a sulcus , sometimes it could
be opened in a genetical disorder called cleft palate which
resultes from failure of fusion along the line from the incisive
foramen until the palatine bone.
New
In a medial view of the maxilla you can see the roof of the
mouth, the floor of the nose and the maxillary sinus which is the
biggest sinus participating in resonance of the sound.
major markings
include
superior alveolar processes are
located at the inferior border of
the maxillary bone
Zygomatic bone
Irregularly shaped,very smooth bones
(cheekbones),that form the
prominences of the cheeks and the
infero-lateral margins of the orbits .
The body of the zygomatic has two processes:
temporal and frontal,but sometimes we have another
process (very small one) that articulates with the maxilla
called anteriorly maxillary process
Anterior to this articular surface there is an opening
(infra orbital foramen) through which the infra
orbital nerve “the trigeminal branch (second division
of the trigemini) will go above and innervate the muscles
of the superior lip.
The zygomaticofacial foramen is in the
middle of this bone.
The Mandible bone
 The
mandible (lower jawbone) is the
largest,strongest bone of the face.
But according to the Drit is not considered a facial bone
 Its
major markings include the
coronoid process, mandibular
condyle,the alveolar margin, and the
mandibular and mental foramina
 Teeth
are embedded in the alveolar
processes of the mandible.
Major Markings of Mandible bone
More about the mandible
New
It articulates with the temporal bone posteriorly.
It has two parts: vertical part called rami(plural of ramus) and horizontal
part which is U-shaped . The mandibular angle is where the ramus meets
the body of mandible, it's easily palpated .The ramus is very smooth in
the lateral aspect, it has three borders:
Anterior border: very smooth and rounded.
Posterior border: Sharper than the anterior.
Superior border: it has a notch; this notch is called the mandibular notch
**Anterior to the notch there is the coronoid process of the mandible.
Posterior to the notch there is articular surface or process which is
mandibular condyle, it has head (enter the articulation with the
mandibular fossa), neck and body.
**The masseter muscle is inserted in the posterior margin of the
mandible , and it will take insertion again from the lateral smooth surface
of the body, the lateral surface has ridges to provide the attachment .
New
cont about the mandible
The body of the mandible has a superior margin and inferior margin, the
inferior margin is important because:
1- it's palpable.
2- The facial artery passes there in the middle between the mandibular
angle and the chin, its pulsation can be felt here.
**The alveolar processes are same like in the maxilla
In the medial surface, you can see the mandibular foramen, it's limited
superior and anterior by a ridge called the lingula of the mandibular
ramus.
** Inferior to the mandibular foramen there is the mylohyoid groove,
where the mylohyoid muscle originates from
New
Cont about the mandible
**Continue to the medial aspect of the body of the mandible,
there is the mylohyoid line continues along the ramus to the
body and divides the body to submandibular fossa and
sublingual fossa and their glands reside in these fossae.
**In The anteriolateral surface, there is the mental foramen.
Anterior to the foramen there is the mental tubercle, it's deeper
in some people and it resultes from fusion of two bones like in
the maxilla.
Other Facial bones:
Nasal bones – thin medially fused two
bones that form the bridge of the nose.
Lacrimal bones – contribute to the
medial walls of the orbit and contain a deep
groove called the lacrimal fossa that houses
the lacrimal sac.
Palatine bones – two bone plates (vertical
and horizontal) that form portions of the hard
palate,the posterolateral walls of the
nasal cavity, and a small part of the
orbits.
Vomer – plow-shaped bone that forms
part of the nasal septum
Inferior nasal conchae – paired,curved
bones in the nasal cavity that form part of
the lateral walls of the nasal cavity.
New
[ High yield points ]
The inferior chonchae is a separate bone while the
superior and middle chonchae are parts from the
ethmoid bone.
The roof of the mouth composed of the palatine bone and
the palatine process of the maxilla , anteriorly you can see
the alveolar processes of the maxilla .the maxilla goes up
to meet a process from the frontal bone in the middle .
And there the nasal bones which are separate bones (they
are two).
New
More about the palatine bone
The horizontal plate of the palatine bone articulates with the
posterior palatine process of the maxilla, the lateral of
palatine there are pterygoid plates which come in contact with
the inferior of the sphenoid.
The palatine nerve passes through the greater palatine
foramen which is located Medial to the maxilla tuberosity.
It has many processes serve as attachment for many muscles
in the pharyngeal and tongue. There are many depressions in
the lateral wall of the nasal cavity. Smokers have accumulation
of mucous in these depressions and this is dangerous
Nasal cavity
 The
nasal septum is made by the
1-Vomer (forms the medial wall of the nose and articulates
with the inferior portion of the perpendicular plate of the ethmoid bone)
2-perpendicular plate of the ethmoid
3-The septal cartilage.
 This
septal cartilage will separate the
naris. (which extend from the external
nasal openings into the internal nasal
openings toward the pharynx (nasopharynx)
Lateral wall of the nasal cavity
Composed of :
The lateral masses **“ talk about them in the
next slide” ** of the ethmoid bone (superior
and middle nasal concha ).
 The perpendicular plate of the palatine
bone.
The inferior nasal choncha (doesn’t belong
to ethmoid bone).
** Medial surface of the lateral masses
will form the lateral wall of the nose.
This medial surface has
protrusions(shell like projection) the
chonca,underneath them we have
meatuses >> into which the nasal,
ethmoid,maxillary,frontal and
the sphenoid sinuses open into.
These shell like projections
(chonca) function to :
Increase the area of contact of the air with
the nasal mucosa,to prevent entering of the
dust particles.
Modulate the temperature of the air (cooling
or heating),and that is because of the highly
vascularized epithelium that covers the nasal
cavity from the inside.
Trap the foreign particles by hair follicles
present in the nose.
Floor of the nasal cavity:
formed by hard plate ( palatine process
of the maxillae and the palatine bone)
Roof the nasal cavity ,very small :
formed by the cribriform plate of the
ethmoid
Para-nasal Sinuses
 Mucosa-lined, air-filled sacs
found in five
skull bones – the frontal, sphenoid,
ethmoid, and paired maxillary bones
 Air enters the paranasal sinuses from the
nasal cavity and mucus drains into the
nasal cavity from the sinuses
 Lighten the skull and enhance the
resonance of the voice
The orbit
A Bony cavity in which the eye are firmly
encased and cushioned by fatty tissue.
Formed by parts of seven bones –
( frontal,sphenoid, zygomatic,maxilla,
palatine,lacrimal,and ethmoid).
The orbital cavity looks like a room, it has a
roof,floor,lateral, medial and posterior
wall.(but no anterior wall)
The Superior border(Roof)of
the Orbit
is made entirely by the:

The limb (the orbital plate) of the
frontal) :which is a very thin material

A small part is made by the lesser
wings of the sphenoid because it
articulates with the posterior aspect of the
limb of the frontal bone and participate in
forming what we call the superior wall.
The Inferior border(Floor)of
the Orbit
made by the zygomatic and maxillary
bones
The Lateral borderof the Orbit
made by:
 greater wing (part of it in the
posterior*) of the sphenoid bone
 inferior extension of frontal bone
 Orbital surface of zygomatic bone
The Medial border of the Orbit
made by :
 The lacrimal bone.
 The lateral surface of the lateral
masses of the ethmoid
 The body of the sphenoid.
 Small part of the maxilla and palatine
process (the vertical area of the palatine)
also participate.
The posterior W all the Orbit
has two fissures:
superior and inferior orbital fissures,
** superior orbital fissure :between the
greater and lesser wings.
** Medial and inferior to the apex of this
superior fissure we have the optic
foramen,and inferior to that we have the
inferior orbital fissure.
Hyoid Bone

Not actually part of the skull, but lies just
inferior to the mandible in the anterior neck

Only bone of the body that does not
articulate directly with another bone.

Attachment point for neck muscles that raise and
lower the larynx during swallowing and speech