The Skull Flashcards
(G) Kranion, (L) Calvaria
Skull
Bones of the Skull and Their Parts
Cranium: 8 bones
(F, P, O, T, S, E)
- Frontal(1) .
- Parietal (2)
- Occipital (1)
- Temporal (2)
- Sphenoid (1)
- Ethmoid (1)
Bones of the Skull and Their Parts
Visceral Cranium: 14 bones
(M, Z, N, L, P, I, V, M)
Maxillae (2)
Zygomatic (2)
Nasal (2)
Lacrimal (2)
Palatine (2)
Inferior conchae or turbinates (2)
Vomer (1)
Mandible (1)
Bones of the Skull and Their Parts
Other bones
(HB, AO)
Hyoid bone (1)
Auditory ossicles
Bones of the Skull and Their Parts
What are the 3 bones in the Auditory ossicles
malleus - 2
incus - 2
stapes - 2
Bones of the Skull and Their Parts
how many bones are in the Teeth?
32 bones
Regions of the Skull
(F, L, P, V, B)
Frontal, anterior or facial (1)
Lateral, right and left (2)
Posterior or occipital (1)
Vertical, superior or vertex (1)
Basal or inferior (1)
Sutures of the Skull (7)
- Coronal suture
- Sagittal suture
- Lambdoidal suture
- Squamosal suture
- Less obvious suture
- Metopic suture
- Two mendosal sutures
Sutures of the Skull
Squamous
Squamosal suture
Sutures of the Skull
a scale, a thin flat plate
Squamosal suture
Squamous
Sutures of the Skull
pass obliquely upwards, one in each half of the squamous part of the occipital bone.
Two mendosal sutures
Sutures of the Skull
pass obliquely upwards, one in each half of the squamous part of the occipital bone.
Two mendosal sutures
The head or condyle of each ramus of the mandible articulates with the mandibular fossa of the corresponding temporal bone.
TMJ — temporomandibular joint
What kind of join is the Temporalmandibular joint
synovial - gliding and hinge joint
are cavities within some of the cranial bones. These sinuses on each side open into the corresponding nasal cavity.
Paranasal Sinuses or accessory nasal sinuses
What are the Paranasal Sinuses
(F,E,M,S)
- Frontal sinuses (2)
- Ethmoidal sinuses (2)
- Maxillary sinuses (2)
Also named as “antra” — (G) antron = a cave - Sphenoidal sinuses (2)
What are the three Cranial Fossae
(A,M,P)
- Anterior cranial fossa (1)
- Middle cranial fossa (1)
- Posterior cranial fossa (1)
Cerebral Cranium
What are the parts of the Frontal bone
- Squamous
- Orbital
- Nasal
Cerebral Cranium: Frontal Bone
squama
Squamous part
Cerebral Cranium: Frontal Bone
Parts of the Squama
(F,S,S,G,F)
Frontal eminence
Supraorbital margins (2)
Supraorbital notches (2)
Glabella (1)
Frontal sinuses (2)
Cerebral Cranium: Frontal Bone
What are the Orbital parts
- Ethmoidal notch
- Orbital plates
Cerebral Cranium: Frontal Bone
Nasal Part
Nasal spine
Cerebral Cranium: Frontal Bone
suture present between two frontal bones
Metopic suture
Cerebral Cranium: Frontal Bone
are two rounded prominences on the squamous part of the frontal bone.
Frontal eminences
Cerebral Cranium: Frontal Bone
ridges of bone that form the superior borders of the circular opening into each
orbit.
Supraorbital margins
Cerebral Cranium: Frontal Bone
small notch or sometimes a foramen located towards the medial end of
each supraorbital margin.
Supraorbital notch (or foramen)
Cererbral Cranium: Front Bone
is a smooth flat area between the medial ends of the supraorbital margins, and above the upper ends of the nasal bones.
Glabella
Cererbral Cranium: Frontal Bone
paired cavities in the squamous part of the frontal bone above the supraorbital margins.
Frontal Sinuses
Cerebral Cranium: Frontal Bone
definite gap between the medial borders of the 2 orbital plates.
Ethmoidal notch
Cerebral Cranium: Frontal Bone
pointed process that forms a small part of the nasal septum behind the nasofrontal articulations.
Nasal spine
Cerebral Cranium
(L) paries - wall
Parietal bones
Cerebral Cranium
(L) paries - wall
Parietal bones
Cerebral Cranium: Parietal Bone
is a rounded prominence on the lateral surface of each parietal bone.
Parietal eminence or parietal tuberosity
Cerebral Cranium: Parietal Bone
The distance between the 2 eminences
The greatest transverse diameter
Cerebral Cranium
Parts of the Occipital bone
(F, SP: EOP, IOP, LP: O,H , BP)
- Foramen magnum
- Squamous part
External occipital protuberance
Internal occipital protuberance - Lateral parts (2)
Occipital condyles (2)
Hypoglossal canals (2) - Basilar part (basal) (1)
Cerebral Cranium
(L) occiput — back part
Occipital Bone
Cerebral Cranium: Occipital Bone
large opening in the inferior part of the occipital bone through which the medulla oblongata of the brain joins the spinal cord
Foramen magnum
Cerebral Cranium: Occipital Bone
oval shaped prominences located on the inferior surfaces of each lateral part.
Occipital condyles
Cerebral Cranium: Occipital Bone
short passages from each lateral margin of the foramen magnum, close to its front
end, that open below in front of the condyles.
Hypoglossal canals
Cerebral Cranium: Occipital Bone
is that part anterior to the foramen magnum.
Basilar part
Cerebral Cranium: Temporal Bone
is a large bony prominence that extend down from the temporal bone posterior to the
ear.
Mastoid Process
Cerebral Cranium: Temporal Bone
long slender sliver-like process that extends down from each temporal bone.
Styloid process
Cerebral Cranium: Temporal Bone
is a slender bony process that extends horizontally forward from the opening of the ear.
Zygomatic process
Cerebral Cranium: Temporal Bone
is a depression on the temporal bone in front of the opening into the ear and below the
origin of the zygomatic process.
Mandibular fossa
Cerebral Cranium: Temporal Bone
shaped somewhat like a pyramid and is sometimes called the petrous pyramid.
(G) petra = rock.
Petrous part
Cerebral Cranium: Temporal Bone
porus, is an opening on the dorsal surface of the petrous part close to its medial end.
Internal acoustic opening
Cerebral Cranium: Temporal Bone
a canal leading from the internal acoustic opening to the inner ear.
Internal acoustic meatus
Cerebral Cranium: Temporal Bone
short passage that begins as a circular opening on the inferior surface of the petrous
pyramid close to its medial end
Carotid canal
Cerebral Cranium: Temporal Bones
forms the anterior and inferior walls of the external acoustic meatus. (G) drum
Tympanic part
Cerebral Cranium
(G) sphen = wedge
Sphenoid bone
Cerebral Cranium: Sphenoid Bone
horizontal depression that crosses the body of the bone in front of the sella turcica.
Chiasmatic groove
Cerebral Cranium: Sphenoid Bone
horizontal depression that crosses the body of the bone in front of the sella turcica.
Chiasmatic groove
Cerebral Cranium: Sphenoid Bone
are 2 short passages extending anteriorly and laterally one from each side of the body.
(G) optikos = eye
Optic canals (OT - optic foramina)
Cerebral Cranium: Sphenoid Bone
saddlelike bony depression on the upper surface of the body of the sphenoid.
(L) sella = saddle, Turcica = Turkish
Sella Turcica
Cerebral Cranium: Sphenoid Bone
posterior wall of sella turcica
Dorsum sella
Cerebral Cranium: Sphenoid Bone
central cavity of the sella turcica
Pituitary fossa (hypophyseal fossa)
Cerebral Cranium: Sphenoid Bone
are two small rounded prominences that are located one at each lateral end of the upper margin of the dorsum sella.
Posterior clinoid processes
Cerebral Cranium: Sphenoid Bone
lie one on each side of the upper anterior surface of the sella turcica
Middle clinoid processes
Cerebral Cranium: Sphenoid Bone
lie one on each side of the upper anterior surface of the sella turcica
Middle clinoid processes
Cerebral Cranium: Sphenoid Bone
is an often poorly defined groove that passes vertically along each lateral surface of the
body.
Carotid groove
Cerebral Cranium: Sphenoid Bone
are 2 bony processes that extend posteriorly from the medial end of the posterior free margin of each lesser wing.
Anterior clinoid processes
Cerebral Cranium: Sphenoid Bone
(round opening) a small opening in the medial basal part of the greater wing just lateral to the superior orbital fissure. Transmit maxillary nerve.
Forament rotundum (round opening)
Cerebral Cranium: Sphenoid Bone
(oval opening) is a larger opening in the basal part of the greater wing lateral to and behind the foramen rotundum. Transmits mandibular nerve.
Foramen ovale (oval opening)
Cerebral Cranium: Sphenoid Bone
comma shaped opening on the medial margin of each greater wing.
Superior orbital fissure
Cerebral Cranium: Sphenoid Bone
pteryx = a wing. Extend down vertically from the inferior surface of the body of the sphenoid bone on each side.
Pterygoid processes
Cerebral Cranium
(G) ethmos = a sieve
Ethmoid bone
Cerebral Cranium: Ethmoid Bone
wedge between the 2 orbital plates of the frontal bone in the ethmoidal notch on the
floor of the anterior cranial fossa. (L) cribrum = sieve
Cribriform plate
Cerebral Cranium: Ethmoid Bone
very thin plate of bone that passes vertically up from the upper surface of the cribiform plate.
Crista galli
Cerebral Cranium: Ethmoid Bone
is a flat sheet of bone that extends down in the midline from the cribriform plate and
forms the nasal septum.
Perpendicular plate
Cerebral Cranium: Ethmoid Bone
(L) concha = a shelf, a curved shelf. Are bony shelves that extend into
the nasal cavities from the lateral walls.
Superior and middle nasal conchae
Visceral Cranium: Maxillae
a large cavity within the body of the maxilla
Maxillary sinus
Visceral Cranium: Maxillae
a ridge of bone that forms the lower border of the orbital opening.
Infraorbital margin
Visceral Cranium: Maxillae
is a small opening on the anterior surface of the maxilla just below the infraorbital margin.
Infraorbital foramen
Visceral Cranium: Maxillae
is a single small pointed projection in the midline at the base of the nasal septum.
Anterior nasal spine
Visceral Cranium: Maxillae
is a small rounded bony prominence posterior to the third upper molar tooth
Maxillary tuberosity
Visceral Cranium: Maxillae
extends up along the lateral side of the nose posterior to the nasal bone, and along the
medial margin of the orbit.
Process
Frontal process
Visceral Cranium: Maxillae
extends up and laterally from the body of maxilla to meet the maxillary process of the
zygomatic bone.
Process
Zygomatic process
Visceral Cranium: Maxillae
extends down from the inferior part of the body of the maxilla to form sockets for eight
upper teeth.
Process
Alveolar process
Visceral Cranium: Maxillae
is a flat shelf of bone that extends medially from the lower part of the body of the maxilla
to meet its mate and form all but the posterior part of the hard palate.
Process
Palatine Process
Visceral Cranium: Maxillae
The Maxillae form parts of the following:
- The floor of the orbit
- The medial part of each infraorbital margin
- The lateral wall of each nasal cavity
- The floor of each nasal cavity
- The roof of the mouth Process
Visceral Cranium
(OT. malar bone)
Quadrilateral in shape
Zygomatic bones
Visceral Cranium: Zygomatic Bone
at its lower margin joins the maxilla
Maxillary process
Visceral Cranium: Zygomatic Bone
joints the frontal bone at the upper lateral margin of the orbit.
Frontal Process
Visceral C ranium: Zygomatic Bone
joints the zygomatic process of the temporal bone to form the long slender zygomatic
arch.
Temporal process
Visceral Cranium
2 small flat bones located in the medial walls of the orbits.
Lacrimal bones
Visceral Cranium
(L) lacrima - a tear
Lacrimal bones
Visceral Cranium
Each bone is an “L” shaped structure, and includes horizontal and vertical plates of the bone.
Palatine bones
Visceral Cranium: Palatine Bone
forms the dorsal part of the lateral wall of the nasal cavity
The vertical part
Visceral Cranium: Palatine Bone
extends medially from the inferior part of the vertical plate to meet the horizontal plate
of the other palatine bone.
Horizontal plate
Visceral Cranium
Each is a thin curved plate of bone that extends medially like a shelf into the nasal cavity from the lateral wall.
Inferior conchae
Visceral Column
Part of Inferior conchae
Inferior turbinate bones
Visceral Cranium
Small flat rectangular shaped bone that joins the nasal part of the frontal bone
Nasal bone
Visceral Cranium
(L) ——- = a ploughshare
Single flat four sided bone plate that resembles a ploughshare.
Vomer
Visceral Cranium
Lower jaw
Mandible
Visceral Cranium
shaped like a horseshoe with its posterior end on each side turned up to articulate with
the temporal bone.
A single mandible
Visceral Cranium
What are the parts of the Mandible
Body and Ramus
Visceral Cranium
What are the parts of the Body of the Mandible
- Angles
- Symphysis
- Mental protuberance
- Mental foramina (2)
- Alveolar part
Visceral Cranium
What are the pats of the Ramus of the Mandible
- Coronoid processes
- Condylar process (neck and head or condyle)
- Mandibular notches
- Mandibular foramina
- Mandibular canals
Visceral Cranium: Mandible
is the flat prominence at the inferior part of the symphysis anteriorly — the chin.
Mental protuberance
Visceral Cranium: Mandible
is a small opening on the outer surface of the body of the mandible on side below the
second premolar tooth.
Mental foramen
Visceral Cranium: Mandible
is a flat thin upward extension of the anterior part of the ramus.
Coronoid process
Visceral Cranium: Mandible
extends upwards from the posterior part of the ramus to the adjacent joint.
Condylar process
Visceral Cranium: Mandible
is half-moon shaped notch between the coronoid and condylar processes of the ramus.
Mandibular notch
Visceral Cranium: Mandible
is an opening on the medial surface of the ramus about its center.
Mandibular foramen
Visceral Cranium: Mandible
is a passage within the lower part of the ramus and body of the mandible.
Mandibular canal
Other bones
Hyoid bone and Auditory Ossicles
Other bone
“U” shaped bone that is located in the anterior part of the neck. It lies horizontally about half-way between the body of the mandible and the thyroid cartilage.
Body and Cornua
Hyoid
Hyoid bone
curved anterior part
Body
Hyoid bone
extends back from the posterior end of the body on each side as a bent process.
Greater cornu
Hyoid bone
much smaller and extends up from the greater cornu on each side.
Lesser cornu
Other bones
3 pairs of Auditory ossicles
- Malleus
- Incus
- stapes
Auditory ossicles
Hammer
malleus
Auditory ossicles
Stirrup
stapes
Each cavity is cone shaped, its base lying in front and its apex at the pointed posterior end. Two (Right and Left)
The Orbit
The Orbit
is formed by the frontal bone.
supraorbital margin of the base
The Orbit
formed by the maxilla and zygomatic bone.
infraorbital margin
The Orbit
formed by the frontal and sphenoid.
roof of the orbit
The Orbit
formed by the maxilla, zygomatic and palatine bones.
The floor
The Orbit
formed by the maxilla, lacrimal, ethmoid, and the body of sphenoid.
The medial wall
The Orbit
by the zygomatic and greater wing of the sphenoid.
The lateral wall
Chambers of the nose extending from the nostrils or openings (nares), on the face to the nasal pharynx, or throat, behind. (two: left and right)
The Nasal Cavities
The Basal Foramina
right and left; form short passages on the lateral margins of the body of the sphenoid under cover of the lesser wings. Transmits optic nerve and ophthalmic artery.
Optic canals (OT. Foramina)
The Basal Foramina
right and left; comma shaped slits in the lateral wall of each orbit close to its posterior
end. Transmits several cranial nerves.
Superior orbital fissures
The Basal Foramina
right and left; are narrow slits between the lateral wall and the floor of the orbit.
Inferior orbital fissures
The Basal Foramina
is a small circular opening at the medial margin of the greater wing of the sphenoid close to
the medial end of the superior orbital fissure. Transmits a maxillary nerve.
Foramen rotundum
The Basal Foramina
is an oval opening in the base of the greater wing of the sphenoid bone posterior and lateral to the foramen rotundum. Transmits mandibular nerve.
Foramen ovale
The Basal Foramina
is a very small circular opening in the greater wing of the sphenoid bone posterior and lateral
to the large foramen ovale. Transmits the middle meningeal artery to the inner surface of the skull.
Foramen spinosum
The Basal Foramina
is ragged opening at the apex of the petrous pyramid between it and the posterolateral margin of the body of the sphenoid bone. it is where the internal carotid artery enters the cranium after it has passed the carotid canal.
Foramen lacerum
The Basal Foramina
is a hole on the inferior surface of the petrous pyramid about 1 cm posterolateral to the apex.
Carotid opening
The Basal Foramina
passes from the carotid opening on the inferior surface of the petrous pyramid through this bone to the foramen lacerum.
Carotid canal
The Basal Foramina
is a large irregular opening located between the lateral part of the occipital bone and the petrous pyramid. The internal jugular vein leaves the cranium through this opening.
Jugular foramen
The Basal Foramina
is a single very large opening in the basal part of the occipital bone.
Foramen magnum
The Basal Foramina
is an opening on the posterior surface of the petrous pyramid above the jugular foramen.
The internal acoustic opening
Are gap in bone formation at the angles where several bones meet. (fonticulus = a fountain)
Fontanelles
Fontanelles
located in the midline of the vertex of the skull where the posterior surface of the frontal bone meets the anterior and upper margins of the parietal bone.
Anterior fontanelle or frontal fontanelle
Fontanelles
lies in the midline on the upper posterior surface of the skull where the pointed end of the occipital bone meets the postprior margins of the two parietal bones.
Posterior fontanelle or occipital fontanelle
(AS) toth
(L) dens
Teeth
__ in the maxillae, ___ in the madible
16
deciduous teeth
20
Teeth
__ permanent
32
parts of the tooth
- crown
- neck
- root
Structure of a Tooth (5)
- Pulp cavity
- dentine
- enamel
- cement
- apical foramen
- peridental membrane
Classification of teeth: permanent
*Molar (12)
*Premolar (8)
*Canine (4)
*Incisor (8)
Parts of the Tooth
is the exposed part, visible in the mouth
Crown
Parts of the Tooth
are small rounded prominences on the surfaces of the premolar and molar teeth
Cusps
Parts of a Tooth
is the constricted part where the crown and root meet
The neck
Parts of a Tooth
the small tapered end, is located in the alveolar process of the maxilla or the alveolar part of the mandible
The root
Parts of a Tooth
is that aspect facing the tongue
Lingual surface
Parts of a Tooth
is its outer aspect facing the lip or cheek
Labial or buccal surface
The Structure of a Tooth
- The pulp cavity
- The dentine
- The enamel
- cement
- the apical foramen
- the peridental membrane
The Structure of a Tooth
is the central cavity within a tooth extending from the crown down the root.
The pulp cavity
The Structure of a Tooth
is modified bone that surrounds the pulp cavity in both the crown and root
The dentine
The Structure of a Tooth
is a thin covering that forms an outer coat for the crown.
The enamel
The Structure of a Tooth
is a layer of modified bone that covers the dentine of the root.
The cement
The Structure of a Tooth
is a minute opening in the tip of the root by which a nerve and an artery enter, and a vein
leaves the pulp cavity.
The apical foramen
The Structure of a Tooth
is a layer of fibrous tissues that surorunds the root of each tooth and attaches it to the wall of the socket in which the tooth lies
The peridental membrane
refers to the position of the upper and lower teeth in relation to each other when the mouth is closed.
Occlusion
the cusps and grooves do not fit into each other, or in some instances opposing teeth may not touch
each other.
Malocclusion
The Function of Teeth
- Incisors bite off mouthfuls of food
- Premolars and molars grind and masticate food.
- The object is to break food into small pieces so that the digestive juices may come into intimate contact
with the food particles when it reaches the digestive organs.
Some Basic Terms Defined
Two cone shaped cavities for the eyeballs
Orbits
Some Basic Terms Defined
is the point at the outer margin where the upper and lower eyelid meets
Lateral canthus
Some Basic Terms Defined
The two chambers of the nose
Nasal Cavities
Some Basic Terms Defined
Is the partition between the two nasal cavities
Nasal septum
Some Basic Terms Defined
Is the pear shaped hole between the two maxillary bones into the nasal cavities
The piriform opening
Some Basic Terms Defined
Are cavities within some of the cranial bones
Paranasal sinuses
Some Basic Terms Defined
Is the expanded cavity at the upper end of the digestive tract
The mouth
Some Basic Terms Defined
Is the chin, the prominence on the anterior part of the mandible at the midline
Mentum
Some Basic Terms Defined
Is the passage leading into the ear and ear drum
External acoustic meatus
Some Basic Terms Defined
Is the opening leading into the ear and eardrum
External acoustic opening
Some Basic Terms Defined
Is a slender bridge of bone that extends on each side from in front of the external acoustic opening to the zygomatic bone below, and lateral to, the orbit
Zygomatic arch
Some Basic Terms Defined
Bony prominence that extends down from the lateral surface of the skull behind the ear
Mastoid process
Some Basic Terms Defined
Protuberance is a small but definite prominence on the occipital bone in the midline
External occipital protuberance
Some Basic Terms Defined
Flat Part
Squamous part
Some Basic Terms Defined
Are unossified area at the junctions where three bones of the skull meet in the infant
Fontanelles
Some Basic Terms Defined
The Point on the vertex of the skull where the sagittal suture meets the coronal suture
Bregma
Some Basic Terms Defined
The point at the posterior end of the sagittal suture where the occipital and two parietal bones are in contact
Lambda
Some Basic Terms Defined
Are three depressions on the inner surface of the floor of the skull
Cranial fossae
Some Basic Terms Defined
Openings in the floor or base of the skull through which nerves and veins leave the cranial cavity or arteries enter it
Basal foramina
Congenital Anomalies
without a head
Acephalus
Congenital Anomalies
two heads, dicepalic
Dicephalus, bicephalus
Congenital Anomalies
a large head, macrocephalic
Macrocephalus
Congenital Anomalies
fluid in the head
Hydrocephalus
Congenital Anomalies
A small head, microcephalic
Microcephalus
Congenital Anomalies
two halves of the soft or hard palate may fail to unite at the midline in the roof of the mouth
Cleft palate
Congenital Anomalies
the upper lip may fail to unite on one side or other
Hare lip deformity