Lecture 26

Front 1

1. Describe the major divisions and bones of the skull.

What landmarks divide the skull?

Back 1

»A line drawn from the supraorbital ridge to the mastoid process separates the skull into two major parts.

Front 2

(Describe the major divisions and bones of the skull)

Which part houses the brain, including the anatomical apparatus for hearing?

Back 2

»Neuocranium

Front 3

(Describe the major divisions and bones of the skull)

Which part is considered the facial region?

Back 3

»Splanchnocranium

Front 4

(Describe the major divisions and bones of the skull)

Paired bones

Back 4

1) Maxilla
2) Palatines
3) Nasals
4) Inferior conchae
5) Lacrimals
6) Zygomatics
7) Temporals
8) Parietals

Front 5

(Describe the major divisions and bones of the skull)

Unpaired bones

Back 5

1) Mandible
2) Vomer
3) Ethmoid
4) Sphenoid
5) Occipital
6) Frontal

Front 6

2. Identify selected landmarks and details of the cranial bones.

Posterior fontanell

Back 6

»Lies at the junctions of the occipital and parietal bones.
»It closes 2-3 months after birth, with the formation of the lambdoid suture.

Front 7

(Identify selected landmarks and details of the cranial bones)

Sutures

Back 7

1) Coronal suture
2) Sagittal suture
3) Lambdoid suture
4) Basilar (spheno-occipital) suture

Front 8

(Identify selected landmarks and details of the cranial bones)

Frontal bone

Back 8

Supraciliary arch
Supraorbital margin and foramen/notch
Temporal lines

Front 9

(Identify selected landmarks and details of the cranial bones)

Maxilla

Back 9

Zygomatic process
Nasal notch
Infraorbital foramen
Alveolar Process
Zygomatic Process
Incisive fossa
Palatine Process

Front 10

(Identify selected landmarks and details of the cranial bones)

Zygomatic

Back 10

Zygomaticofacial foramen
Frontal Process
Temporal Proces
Maxillary and oribital borders

Front 11

(Identify selected landmarks and details of the cranial bones)

Parietal

Back 11

Superior Temporal line
Inferior Temporal line

Front 12

(Identify selected landmarks and details of the cranial bones)

Temporal

Back 12

Squamous
Mastoid
Petrous

Tympanic parts:
(i)External auditory meatus, (ii)styloid process, (iii)glenoid (condylar) fossa, (iv)postglenoid tubercle, (v)zygomatic process, (vi)articular tubercle, (vii)and mastoid process

Front 13

(Identify selected landmarks and details of the cranial bones)

Occipital

Back 13

External occipital protuberance
External occipital crest
Superior and inferior nuchal lines
Foramen Magnum
Basioccipital
Occipital Condyles

Front 14

3. Describe the anatomy of the scalp.

SCALP

Back 14

Skin
Connective Tissue
Aponeurosis (galeae aponeurotica)
Loose subaponeurotic connective tissue
Periosteum

Front 15

(Describe the anatomy of the scalp)

Extends

Back 15

Extends from superior nuchal line to supraorbital margins and laterally, between the zygomatic arches.

Front 16

(Describe the anatomy of the scalp)

Sensory innervation

Back 16

»Anterior to the ears, branches of the trigeminal n. supply the scalp.

»Posterior to the ears, branches from spinal nerves C2 and C3 supply the scalp.
»Greater occipital n. and lesser occipital n.

Front 17

(Describe the anatomy of the scalp)

Arterial supply

Back 17

1) Branches of external carotid a. - (i) Occipital a. (ii) Posterior auricular a. (iii) Superficial temporal aa.

2) Branches of internal carotid a. - (i)Supratrochlear and (ii) supraorbital a.

Front 18

(Describe the anatomy of the scalp)

How can blood flow through the supraorbital a. be monitored?

Back 18

»It can be monitored by Doppler ultrasound devices.
»This may be done to indirectly assess the quantity of blood flow in the internal carotid a.

Front 19

(Describe the anatomy of the scalp)

Venous drainage

Back 19

1) Supraorbital and supratrochlear vv. united at the medial angle of the eye to form the angular v. which communicates with the opthalmic vv.
»This angular v. continues as the facial v.

2)The superficial temporal v. joins the maxillary v. to form the retromandibular v.

Front 20

(Describe the anatomy of the scalp)

Venous drainage:
What is one problem of having the supraorbital and supratrochlear vv. unite at the medial angle of the eye to form the angular v. that communicates with the opthalmic vv.?

Back 20

»This may allow facial infections to reach the cavernous sinus.

Front 21

(Describe the anatomy of the scalp)

Infections of the scalp

Back 21

»Infections of the scalp may pass to the venous sinuses of the dura mater via emissary vv..

»Emissary vv. then passes through the parietal foramina to the superior sagittal sinus and other intracranial venous sinuses.
»Thus scalp lesions as well as facial infections can result in meningitis.

Front 22

4. Identify and describe the muscles of facial expression.
[25,26]

Innervations

Back 22

»All mm. of facial expression are supplied by branches of the facial n. (CN VII).
»The facial n. has six branches: The posterior auricular and 5 that branch within the parotid gland. These are:
(i) Temporal
(ii) Zygomatic
(iii) Buccal
(iv) Mandibular
(v) Cervical

Front 23

(Identify and describe the muscles of facial expression)

Muscles of the mouth

Back 23

Orbicularis oris
Depressor anguli oris
Zygomaticus major
Levator anguli oris

Front 24

(Identify and describe the muscles of facial expression)

Muscle of eyelids (of facial expression)

Back 24

Orbicularis oculi
(i)Thin palpebral part that closes the eyelids lightly (blinking) to keep cornea moist

(ii) Thick orbital part that closes the eyes tightly to protect them, as during squinting.

Front 25

(Identify and describe the muscles of facial expression)

Muscles of the nose

Back 25

Nasal
Procerus

Front 26

5. Describe the sensory innervation of the face.

Opthalmic n. branches

Back 26

»Frontal n. - divides into the supratrochlear and supraorbital nn.

Front 27

(Describe the sensory innervation of the face)

Maxillary n. branches

Back 27

»Infraorbital n.
»Zygomaticofacial n.
»Zygomaticotemporal n.

Front 28

(Describe the sensory innervation of the face)

Mandibular n. branches

Back 28

»Supplies mandibular region, including lower toothrow.
MOTOR INNERVATION - Mm. of mastication

Major branches:
(i) Inferior alveolar n.
(ii) Lingual n. - General somatic sensation from the mucous membrane of anterior 2/3 of tongue.

Front 29

(Describe the sensory innervation of the face)

Small contributions to general sensation at the face.

Back 29

(i) Facial n. (some skin at auricle)
(ii) Great auricular n. - From the cervical plexus.

Front 30

6. Describe the arteries and veins of the face.

Arteries

Back 30

1) Facial a. - Branch of external carotid a.. Ascends face deep to zygomaticus major toward medial angle of eye, where its continuation is called the angular a.

2) Superficial temporal a. - Deep to parotid gland and ascends posterior to the neck of the mandible and superficial to zygomatic arch.

3) Transverse facial a. - Branch of superficial temporal a. that crosses the face superficial to masseter m. to anastomose with branches of facial a.

Front 31

(Describe the arteries and veins of the face)

Veins

Back 31

1) Facial v.
2) Superficial temporal v.