Maxillofacial Head

7/31/2019 Maxillofacial Head

1/308

Review of Structures of the Head and Neck

Presented by:Dr. Joaquin masoud C. shaee


2/308

Major features of the skull Mastoid process

Styloid process External auditory/acoustic meatus(ear opening)

Ear drum Hyoid bone Epiglottis Thryroid cartilage Cricoid cartilage

Tracheal rings


3/308


4/308

Major features of the skull Zygomatic arch "

Ethmoid " Orbit "

Nasal aperture "

(choanae inside) "


5/308


6/308

Muscles of Face


7/308

You are responsible for muscles described in class Origin Insertion Action

Nerve - innervation (if given) Be able to recognize muscles in all diagrams of text


8/308

The organization of the muscles of facial expression differs from that of muscles in most other regions of the body

There is no deep membranous fascia beneath the skin Instead, many small slips of muscle attached to the facial skeleton Insert directly into the skin

Facial muscles can cause movement of the facial skin that reflects emotions They are grouped mainly around the orifices of the face Dilators of the facial orifices and that the function of facial expression has

developed secondarily. Embryologically, they are derived from the mesenchyme of the second

branchial arch Innervated by the facial nerve Topographically and functionally the muscles of facial expression may be

subdivided into epicranial, circumorbital and palpebral, nasal, andbuccolabial groups


9/308

Epicranius: occipitofrontalis

Circumorbital and palpebral group: orbicularis oculi, corrugatorsupercilii and levator palpebrae superioris

Nasal: comprises procerus, nasalis and depressor septi Buccolabial group of Muscles


10/308

Epicranius consists of occipitofrontalis It consist of four thin, muscular quadrilateral parts two occipital and two frontal, connected by the epicranial aponeurosis Occipital part O: lateral two-thirds of the highest nuchal line of the occipital bone

and part of the mastoid part of the temporal bone I: Epicranial aponeurosis at coronal suture


11/308


12/308

Each frontal part (frontalis) is adherent to the superficial fascia O: fibres blend with those of adjacent muscles - procerus, corrugator

supercilii and orbicularis oculi I : epicranial aponeurosis in front of the coronal suture


13/308


14/308


15/308

Muscles of the Face


16/308

The epicranial aponeurosis covers the upper part of the cranium and, with the epicranial muscle It forms a continuous bromuscular sheet extending from the occiput to

the eyebrows


17/308

The circumorbital and palpebral group of muscles are orbicularisoculi, corrugator supercilii and levator palpebrae superioris

Orbicularis oculi is a broad, flat, elliptical muscle Surrounds the circumference of the orbit and spreads into the

regions of the eyelids, anterior temporal region, infraorbital cheekand superciliary region


18/308

It has orbital, palpebral and lacrimal O: orbital part arises from the nasal component of the frontal bone, the fr

process of the maxilla, lacrimal crest andlacrimal bone I: upper orbital bres blend with the frontal part of occipitofrontalis and

corrugator supercilii. Many of them are inserted into the skin and subcutaneous tissue of the

eyebrow, constituting depressor supercili


19/308


20/308

Orbicularis oculi


21/308

Orbicularis oculi is supplied by temporal and zygomatic branches of the facinerve

Action: sphincter muscle of the eyelids and plays an important role in faciexpression and various ocular reexes

The orbital portion is usually activated under voluntary control


22/308


23/308


24/308

Action: cooperates with orbicularis oculi, drawing the eyebrowsmedially and downwards to shield the eyes in bright sunlight

It is also involved in frowning.

The combined action of the two muscles produces mainly vertical wrinkles on the supranasal strip of the forehead


25/308

The nasal muscle group comprises procerus, nasalis and depressor septi Procerus O: arises from a fascial aponeurosis covering the lower part of the nasal

bone and the upper part of the lateralnasal cartilage. I: into the skin over the lower part of the forehead between the eyebrows

Innervation: supplied by temporal and lower zygomatic branches from thefacial nerve

Actions: draws down the medial angle of the eyebrow and producestransverse wrinkles over the bridge of the nose.

It is active in frowning and 'concentration',


26/308


27/308

Nasalis: divided in two parts Compressor Naris and Dilator Naris Compressor Naris O: Maxilla lateral to nasal notch I: at the bridge of nose through aponeurosis Action: Compress nasal aperture Dilator Naris O: Maxilla medial and below copressor I: cartilagnous ala nasi

Action: widening of ant. Nasal aperture Innervation: Buccal branch of facial N


28/308


29/308


30/308

BUCCOLABIAL GROUP OF MUSCLES: include elevators,retractors and evertors of the upper lip

levator labii superioris alaeque nasi, levator labii superioris zygomaticus major and minor, levator anguli oris and risorius)

Depressors, retractors and evertors of the lower lip (depressor labiiinferioris, depressor anguli oris, and mentalis) Compound sphincter (orbicularis oris, incisivus superior andinferior), buccinator


31/308

Levator labii superioris alaequae nasi O: Fronatal process of maxilla I: By two slips medial and lateral Medial slip inserted in great alar cartilage Lateral slip inserted in lateral part of upper lip with levator labi superioris a

orbicularis oris Innervation: zygomatic and buccal branches of the facial nerve Action The lateral slip raises and everts the upper lip The medial slip dilates the nostril


32/308

Levator labii superioris O: from infraorbital margin I: upper lip between levator labi aleque nasi and zygomaticus minor Innervation: zygomatic and buccal branches of the facial N Actions: Levator labii superioris elevates and everts the upper lip


33/308

Muscles of facial expression Zygomaticus

O: zygomatic bone

I: corners of mouth Action: smiling Nerve: facial / CN VII Buccal and zygomatic

M a j o r a n d M i n o r


34/308


35/308


36/308

Mentalis O: Incisive fossa of mandible I: Skin of chin

Innervation : the mandibular branch of the facial nerve Actions raises the lower lip, wrinkling the skin of the chin it helps in protruding and everting the lower lip in drinking andalso in expressing doubt


37/308


38/308

Depressor labii inferioris O: oblique line of mandible I: blend with opposite side and orbucularis oris Innervation by the mandibular branch of the facial nerve

Actions Depressor labii inferioris draws the lower lip downwards It contributes to the expressions of irony, sorrow, melancholy and

doubt.


39/308


40/308

Depressor anguli oris O: Mental tubercule and oblique line of mandible I: angle of mouth with orbicularis oris Innervation by the buccal and mandibular branches of the facial nerve

Actions Depressor anguli oris draws the angle of the mouth downwards and

laterally in opening the mouth and in expressing sadness


41/308

Buccinator O: alveolar process of maxilla and mandible, anterior margin of

pterygomandibular raphe I: near modiolus at angle of mouth

Innervation : by the buccal branch of the facial nerve. Actions Buccinator compresses the cheek against the teeth and gums during

mastication, and assists the tongue in directing food between theteeth

When the cheeks have been distended with air, the buccinatorsexpel it between the lips, an activity important when playing windinstruments, accounting for the name of the muscle (Latin buccinator = trumpeter).


42/308


43/308

Risorius O: Fascia of cheek I: underside of skin over modiolus

Innervation: supplied by buccal branches of the facial nerve Actions Risorius pulls the corner of the mouth laterally in numerous facial

activities, including grinning and laughing


44/308


45/308


46/308


47/308


48/308


49/308

On each side of the face a number of muscles converge towards a focus just lateral to the buccal angle, where they interlace to form a dense,compact, mobile, bromuscular mass called the modiolus


50/308


51/308

Human Anatomy, Frolich, Head/Neck I: Introductionthe Skull


52/308


53/308

1. Frontal Sinus


54/308

2. Maxillary Sinus3. Ethmoid Sinus4. Spenoid Sinus5. Sella Turcica6. Occipital Bone7. Mastoid Air Cells8. Floor of posterior fossa9. Anterior arch of C-110. Mandible11.Coronal Suture

10

9

1

2

3

4

5

6

7

8

11

LATERAL SINUS & SKULL


55/308

1. Lat. & Med. ptyergoid


56/308

3

2

4

6

plate2. Ethmoid Sinus3. Odontoid Process4. Sphenoid Sinus5. Foramen ovale6. Maxillary Sinus7. Mastoid air cells8. Ant arch of C-19. Margin of foramen

magnum10. Ext. auditory canal

79

1

5

8

10

BASE OF SKULL


57/308

CT SKULL BASE

CAROTID CANAL

JUGULAR FORAMEN


58/308

CT SKULL BASE

MANDIBULARCONDYLE

MASTOID AIR CELLS


59/308

CT SKULL BASE

ZYGOMATIC ARCH

EXTERNALAUDITORY

CANAL


60/308


61/308

CT SKULL BASE

CAROTID CANAL

MIDDLE EAR OSSICLES

MALLEUS

INCUS


62/308

CT SKULL BASE

IACINTERNAL AUDITORY CANAL

CAROTID CANAL

OSSICLESMALLEUS

INCUS


63/308

LATERALNECK1. Hard pallate2. Soft pallate3. Nasopharynx4. Oropharynx

12

3

4

AIRWAY


64/308

1

2

3

4

AIRWAY1. Calcified tracheal

cartilage rings2. Hyoid bone3. Epiglottis4. Thyroid cartilage5. Cricoid cartilage

5

LATERAL VIEW OF NECK

SWALLOWINGSTUDY


65/308

STUDY

1 2

3 4

Note hyoid bone moves anteriorly and superiorly with swallowing .


66/308

5

2

3

6

4

ARTERIOGRAM

1. Internal CarotidArtery

2. Intracranial Carotid3. Maxillary Artery4. Occipital Artery5. External Carotid

Artery6. Common Carotid

Artery7. Facial Artery

17

CT SINUS


67/308

1 1. Frontal Sinus

CT- SINUSAXIAL VIEW

Scans start superiorly and are shown going inferiorly

CT SINUS


68/308

1. Ethmoid Sinus2. Sphenoid

Sinus3. Carotid canal

1

2

3

CT- SINUSAXIAL VIEW

CT- SINUS


69/308

1. Maxillary Sinus

2. Med. & Lat.Pterygoid plate

3. Nasopharynx

4. Nasal septum

5. Inferior turbinate

1

23

4

5

CT- SINUSAXIAL VIEW

CT- SINUS


70/308

1. Maxillary Sinus

2. Hard Palate

3. Mandible

4. Masseter muscle

3

2

1

3

4

4

AXIAL VIEW

CT- SINUS


71/308

1. Fronto-nasalsuture

2. Frontal sinus3. Nasal bones

1

2

3

Coronal sections extending fromanterior to posterior

CT- SINUS


72/308

1. Ethmoid sinus2. Inferior turbinate

3. Middle turbinate

1

2

3

CORONAL VIEW

CT- SINUS


73/308

1. Maxillary

sinus2. Nasal

Septum

1

2

CT SINUSCORONAL VIEW

CT- SINUS


74/308

1. Sphenoidsinus

2. Hard Palatte

1

2

CORONAL VIEW


75/308


76/308


77/308

MASTOIDS

NASOPHARNYX

MAXILLA LT

EXTERNALAUDITORYMEATUS

MANDIBULARCONDYLE

SCAN LEVEL


78/308


79/308

SCAN LEVEL

SUBCUTANEOUSFAT

SUBMANDIBULARGLAND

EPIGLOTTIS

STERNOCLEIOMASTOIDMUSCLE

LT


80/308


81/308


82/308

SCAN LEVEL

THYROID CARTILAGE

CRICOIDCARTILAGE

JUGULARVEIN

COMMON CAROTIDARTERY

LT


83/308

SCAN LEVEL

CLAVICLECLAVICLE

THYROIDGLAND

F A T

LT

TRACHEA ESOPHAGUS

l


84/308

Cranial Nerves Special Sense Nerves

I,II,VIII Somatic Motor Nerves

EyeIII,IV,VI Tongue--XII

Rest of body nerves IX,X,XI

Face and jaws VII, V


85/308


86/308

Head I: Skulla framework to hang on Overall organization of skull Base of the skullthe hard part

Developmental view Cranial nerves out (to targets )

Head II: Throat targets Head III: Special Sense targets Head IV: Cranial nerves in depth

Nerve targets in head


87/308

Nerve targets in head SENSORYSpecial GeneralSmell skin Vision teethHearing eye

tongue

oral cavitynasal cavitymiddle earthroatmeninges

MOTORMuscles Glandseyes salivary

extrinsic sweatintrinsic lacrimal

jaws mucous

facial expressionlarynxtonguethroatear

Base of the skullcranial nerves out


88/308

Base of the skull cranial nerves out Ethmoid (olfactory)

I. Olfactory Sphenoid (optic)

II. OpticIII. Oculomotor IV. Trochlear VI. Abducens

Temporal (otic)VII. Acoustic/Auditory/

Vestibulocochlear Face/Jaws

V. Trigeminal

VII. Facial Throat (rest of body)IX GlossopharyngealX. VagusXI. Spinal AccessoryXII. Hypoglosal


89/308

Special Sense Nerves

Internal auditorymeatus (temporal)Inner ear VIII. Auditory

Optic canal(sphenoid)

RetinaII. Optic

Cribiform plate

(ethmoid)

Olfactory

epithelium

I. Olfactory

EXIT FROMCRANIAL CAVITY

TARGETNERVE


90/308

Somatic Motor Nerves


91/308

(eye muscles and tongue) EXIT CR. CAVITYTARGETNERVE

Hypoglossal canal(occipital)

Intrinsic, extrinsicmm. of tongue

XII. Hypoglossal

Sup.,med.,inf.rectus Inferior Oblique Levator palpebraesuperioris

III. Oculomotor (Also parasympatheticto ciliary mm, constrictor pupillae)

Lateral rectusVI. Abducens

Sup. Orbital fissure(sphenoid)

Superior oblique m.(with trochlea)

IV. Trochlear


92/308

Human Anatomy, Frolich, Head/Neck IV: Cranial Nerves


93/308


94/308

Rest of body nervesf f


95/308

(all exit from jugular foramen)NERVE TARGET

X: Vagus Somatic motor to larynx/pharynx Parasympathetic to most of gut Taste to back posterior pharynx

XI: (Spinal)Accesory

Motor to traps,sternocleidomastoid

IX: Glosso-pharyngeal

Sensory to carotid body/sinus Taste to posterior tongue Sensory to ear opening/middle

ear Parotid salivary gland


96/308


97/308

VII: Facial Nerve


98/308

(exits cranial cavity with VIII--internal auditory meatus)

Facial muscles (ve branches fan out over face from stylomastoidforamen) Temporal Zygomatic Buccal Mandibular Cervical

chorda tympani (crosses interior ear drum to join V 3 ) Taste to anterior 2/3 of tongue Submandibular, sublingual salivary glands

Lacrimal glands


99/308

V: Trigeminal (3 nerves in 1!)


100/308

V: Trigeminal (3 nerves in 1!) V1. Ophthalmic

Exits with eye muscle group (superior orbital ssure, through orbit tosuperior orbital notch/foramina)

Sensory to forehead, nasal cavity V2. Maxillary

Exits foramen rotundum through wall of maxillary sinus to inferior orbiforamina)

Sensory to cheek, upper lip, teeth, nasal cavity V3. Mandibular

Exits foramen ovale to mandibular foramen to mental foramen

Motor to jaw muscles--Masseter, temporalis, pterygoids, digastric Sensory to chin Sensory to tongue


101/308


102/308

Cranial Nerve: Major Functions:I Olfactory smell


103/308

II Optic vision

III Oculomotor eyelid and eyeball movement

IV Trochlear innervates superior obliqueturns eye downward and laterally

V Trigeminal chewingface & mouth touch & pain

VI Abducens turns eye laterally

VII Facial controls most facial expressionssecretion of tears & salivataste

VII Vestibulocochlear(auditory)

hearingequillibrium sensation

IX Glossopharyngeal tastesenses carotid blood pressure

X Vagus senses aortic blood pressureslows heart ratestimulates digestive organstaste

XI Spinal Accessory controls trapezius & sternocleidomastoidcontrols swallowing movements

XII Hypoglossal controls tongue movements


104/308

When the tongue and face areaffected on the same side ashemiplegia the lesion must be abovethe XII and VII nucleus respectively

Important diagnostic rules


105/308

Unilateral V, VII, and VIII Cerebellopontine angle lesion Unilateral III, IV, V and VI Cavernous sinus lesion Combined unilateral IX, X, and XI Jugular foramensyndrome

Combined bilateral X, XI, and XII LMN = bulbar palsy UMN = pseudobulbar palsy

Prominent involvement of eye muscle and facial weaknessesp when variable = myasthenia gravis

The most imp cause of brain disease in young age ismultiple sclerosis and in older age is vascular dis

Important diagnostic rules


106/308


107/308

I. Olfactory The olfactory nerve has only a specialsensory component.

Special sensory (special afferent)-Functions in the special sense of smell orolfaction.

The olfactory system consists of theolfactory epithelium, bulbs and tractsalong with olfactory areas of the braincollectively known as the rhinencephalon.


108/308


109/308


110/308


111/308


112/308


113/308


114/308


115/308


116/308


117/308

Functions of the Optic Nerve General Eyelids, orbital globe

Pupils Light reex, accomodation reex Acuity due to ocular, optic, or retinal abn. If reduced acuitycorrectable by pinhole then ocular

Fields Fundi


118/308


119/308

v The right half of the retina receives stimuli from theleft visual eld.v The left half of the retina receives stimuli from theright half of the visual eld.v The upper half of the retina receives stimuli fromthe lower half of the visual eld.v The lower half of the retina receives stimuli fromthe upper half of the visual eld.


120/308

III. Oculomotor A. Somatic motor (general somatic efferent)Supplies four of the six extraocular muscles of the eye and the levator palpebrae superioris muscle of the upper eyelid.

B. Visceral motor (general visceral efferent)Parasympathetic innervation of the constrictor pupillae and ciliary muscles.


121/308


122/308

The somatic motor component of CN III

innervates the following four extraocularmuscles of the eyes:

Ipsilateral inferior rectus muscle

Ipsilateral inferior oblique muscle

Ipsilateral medial rectus muscle

Contralateral superior rectus muscle


123/308


124/308

Lower motor neuron lesion of


125/308

1. 1. Downward, abducted eye on the affectedside rectus muscles.2. Strabismus3. Ptosis (eyelid droop) on the affected side4. Dilation of the pupil on the affected side5. Loss of the accomodation reflex on the

affected side.

Lower motor neuron lesion of Oculomotor nerve:


126/308

IV. Trochlear NerveSomatic motor (general somatic efferent)Somatic motor innervates the superior oblique muscle

of the contralateral orbit.


127/308


128/308

Extorsion (outward rotation) of the affected eye.

Vertical diplopia (double vision) due to the extortedeye. Weakness of downward gaze most noticeable onmedially-directed eye. This is often reported asdifculty in descending stairs.

IV Trochlear Nerve lesion


129/308


130/308


131/308

V. Trigeminal Nerve


132/308


133/308


134/308


135/308


136/308

VI. Abducent Nerve

Supplies the ipsilateral lateralrectus extraocular muscle


137/308

1 Medially directed eye on the affected side dueVI Abducent Nerve lesion


138/308

1. Medially directed eye on the affected side dueto the unopposed action of the medial rectus muscle.2. Inability to abduct the affected eye beyond themidline of gaze (up to approximately the midline, thesuperior and inferior oblique muscles can abduct the

eye).3. Strabismus - the inability to direct both eyes to thesame object. When asked to look at an object locatedlaterally to the side of the lesion, the patient's affected

eye will be unable to be abducted beyond the midlineof gaze. The opposite normal eye will be adducted toeffectively fixate on the object.


139/308

4. Horizontal diplopia (double vision) due to the

strabismus.Patients may compensate by turning

their head so that the affected eye is focused on

an object and then moving the normal eye so asto xate on the object. CN VI paralysis is the most common isolatedpalsy due to the long peripheral course of thenerve.

Damage to the pontine lateral gaze center may result in conjugate paralysis of lateral gaze to the


140/308

may result in conjugate paralysis of lateral gaze to theaffected side.This is indicated by an inability of the patient to xate on anobject placed laterally to the affected side. specically it is:

Inability to abduct the eye on the affected side pastapproximate midline gaze. Inability to adduct the eyeopposite the lesion past midline gaze.

The end result is that neither eye is moved to effectivelyxate on the target object.


141/308

VII. Facial Nerve


142/308


143/308


144/308


145/308


146/308


147/308


148/308


149/308


150/308


151/308


152/308


153/308


154/308

VIII. Vestibulocochlear Nerve


155/308


156/308


157/308

IX. GlossopharyngealNerve


158/308

X. Vagus Nerve


159/308


160/308

Exam of Nerve IX and X Aah reex; uvula moves centrally If it moves to one side; Vagus lesion on the oppos side If it doesnt move, bilat palatal m paraesis Uvula moves on saying ahh but not on gag: IX palsy Gag reex: touch the post pharyngeal wall afferent : Nerve IX,

efferent: X


161/308


162/308

XI. Accessory Nerve


163/308


164/308


165/308


166/308

XII. Hypoglossal Nerve


167/308


168/308


169/308

Special Senses Taste Smell Vision Hearing/Balance

TASTE: how does it work?


170/308

Taste buds on tongue on fungiformpapillae (mushroom-likeprojections)

Each bud contains several celltypes in microvilli that projectthrough pore and chemically sensefood

Gustatory receptor cellscommunicate with cranial nerveaxon endings to transmit sensationto brain

Five taste sensations


171/308

Sweetfront middle Sourmiddle sides Saltyfront side/tip

Bitter back umamiposterior

pharynx

CranialNerves of


172/308

Nerves ofTaste

Anterior 2/3 tongue: VII (Facial)

Posterior 1/3 tongue: IX Glossopharyngeal)Pharynx: X (Vagus)

M&M, Fig. 16.2

Smell: How does it work?


173/308

Olfactory epithelium in nasal cavity with specialolfactory receptor cells Receptor cells have endings that respond tounique proteins

Every odor has particular signature that triggers acertain combination of cells

Axons of receptor cells carry message back tobrain

Basal cells continually replace receptor cellsthey are only neurons that are continuously

replaced throughout life.

Olfactory epithelium just under cribiform plate(of ethmoid bone) in superior nasal epitheliumat midline


174/308


175/308

Vision1. Movement of eyeextrinsic eye muscles and location in

orbit2. Support of eyelids, brows, lashes, tears, conjunctiva3. Lens and focusingstructures of eyeball and eye as optical

device4. Retina and photoreceptors

Movement of


176/308

Movement ofeye

Extrinsic eye muscles


177/308

Muscle " Movement " Nerve "Superioroblique "

Depresses eye,turns laterally "

IV (Trochlear) "

Lateral rectus " Turns laterally " VI (Abducens) "Medial rectus " Turns medially " III (Oculomotor) "

Superior rectus " Elevates " III (Oculomotor) "

Inferior rectus " Depresses eye " III (Oculomotor) "Inferior oblique " Elevates eye, turns

laterally "

III (Oculomotor) "

M&M, fig. 16.4


178/308

Support/Maintenance of Eye b h d h ld f


179/308

Eyebrows: shade, shield for perspiration Eyelids (palpebrae): skin-covered folds with tarsal

plates connective tissue inside Levator palpebrae superioris muscle opens eye (superior portion is smooth musc

why?)

Canthus (plural canthi): corner of eye Lacrimal caruncle makes eye sand at medial corner Epicanthal folds in many Asian people cover caruncle Tarsal glands make oil to slow drying

Eyelashciliary gland at hair follicleinfection is sty Eyelashestouch sensitive, thus blink

Support of Eye--conjunctiva


180/308

Mucous membrane that coats inner surface ofeyelid (palpebral part) and then folds backonto surface of eye (ocular part)

Thin layer of connective tissue covered withstratied columnar epithelium

Very thin and transparent, showing blood vessels underneath (blood-shot eyes) Goblet cells in epithelium secrete mucous tokeep eyes moist

Vitamin A necessary for all epithelialsecretionslack leads to conjunctiva dryingupscaly eye

Support of eye--tearsM&M, fig. 16.5


181/308

Lacrimal glandssuperficial/lateral in orbit,produce tears

Lacrimal duct (nasolacrimalduct) medial corner of eye carriestears to nasal cavity(frequently closed innewbornsopens by 1 yr usually)

Tears contain mucous,antibodies, lysozyme (anti-bacterial)

Eye as lens/optical device


182/308

Light path: Cornea Anterior segment PupilLens Posterior segment Neural layer of retinaPigmented retina

Eye as optical device--structures Sclera (brous tunic): is tough connective tissue ball that forms outsid


183/308

Sclera (brous tunic): is tough connective tissue ball that forms outsidof eyeball like box/case of camera Corresponds to dura mater of brain

Cornea: anterior transparent part of sclera (scratched cornea is typicalsports injury); begins focusing light

Choroid Internal to sclera/cornea Highly vascularized Darkly pigmented (for light absorption inside box)

Ciliary body: thick ring of tissue that encircles and holds lens Iris: colored part of eye between lens and cornea, attached at base to

ciliary body Pupil: opening in middle of iris Retina: sensory layer that responds to light and transmits visual signal to

brain

M&M, fig. 16.4


184/308

Detail: Aperture and focus APERTURE


185/308

Pupil changesshape due tointrinsic autonomicmuscles

Sympathetic: Dilator

pupillae (radial bers) Parasympathetic:sphinchter pupillae

FOCUS "" Ciliary muscles in ciliary body pull on lens to focus far away " Elasticity of lens brings back to close focus " Thus, with age, less elasticity, no close focus far-sighted "

M&M, fig. 16.8


186/308

Detail: eye color Posterior part of iris always brown in color People with brown/black eyes with pigment throughout iris People with blue eyesrest of iris clear, brown pigment at

back appears blue after passing through iris/cornea

Details: Retina and photoreceptors Retina is outgrowth of brain Neurons have specialized receptors at end with photo pigment


187/308

proteins (rhodopsins) Rod cells function in dim light, not color-tuned Cone cells have three types: blue, red, green In color blindness, gene for one type of rhodopsin is decient, usually red or

green Photoreceptors sit on pigmented layer of choroid. Pigment from

melanocytes--melanoma possible in retina!! Axons of photoreceptors pass on top or supercial to photoreceptor

region Axons congregate and leave retina at optic disc (blind spot)

Fovea centralis is in direct line with lens, where light is focused mostdirectly, and has intense cone cell population (low light night visionbest from side of eye)

Blood vessels supercial to photoreceptors (retina is good sight to checkfor small vessel disease in diabetes)

Retina andphotoreceptors


188/308

p p

Ear/Hearing


189/308

Outer Ear: auricle is elastic cartilage attached to dermis, gathers sound Middle ear: ear ossicles transmit and modulate sound Inner ear: cochlea, ampullae and semicircular canals sense sound and

equilibrium

M&M, fig. 16.17

Middle Ear External auditory canal ends at

tympanic membrane which vibratesagainst malleus on other side


190/308

against malleus on other side

Inside middle ear chamber malleus incus stapes which vibrates on oval window of innerear

Muscles that inhibit vibration when

sound is too loud Tensor tympani m. (inserts on

malleus) Stapedius m. (inserts on stapes)

Inner Ear/Labyrinth


191/308

Static equilibrium, linear motion Utricle, saccule are egg-shaped sacs in center (vestibule) of labyrinth

3-D motion, angular acceleration 3 semicircular canals for X,Y,Z planes

Sound vibrations Cochlea (snail)

M&M, fig. 16.20

Auditory Nerve (Acoustic) VIIIreceives stimulus from all to brain

Vestibular n.equilibriumCochlear n.hearing


192/308

Throat/ Pharynx


193/308

Overview: Sagittal view of nose/mouth/throat Nasal Cavity and Breathing Mouth and Chewing Throat and Swallowing Larynx and Singing

Sagittal Section Head Cranial cavity Brain/Spinal cord


194/308

Vertebral bodies Epaxial muscles

Hard/soft palate Oral cavity Esophagus Trachea Epiglottis Naso- Oro-

Laringo-

pharynx "

Nose/Nasal Cavity and Breathing


195/308

Nose/Nasal Cavity and BreathingFunction: Inlet for air to lung Warm/lter air

(mucous membranes onethmoid conchae )

Smell(nerve endings on nasalmembranes)

Conchae of Ethmod Bone


196/308

Scroll-like bones Covered in mucous membrane for

Smell Filter air

W i

Sinuses All connected to nasal

cavity


197/308

cavity All lined with mucous

membranes Cold/allergiesll with

mucous=sinusheadache

Maxillary " Ethmoid "

Frontal "

Sphenoid "

Mouth/Oral Cavity and ChewingFUNCTION "


198/308

COMPONENTS Lips Cheeks

Palate Jaws and teeth Salivary glands

FUNCTION

Bite and chew food " Form words "

Taste "

Kiss "

Vestibulein front of teeth "Oral cavity properbehind teeth "

Lined by thickstratied squamousepithelium (almost

no keratin)"

LipsFUNCTION


199/308

Close mouth Keep food in Make speech sounds Tactile

STRUCTURE Core of sphinchter-shape skeletal muscle

(orbicularis oris) Red margin transition from keratinized

skin to oral mucosa Red because clear color lets underlying vessels show through

No sweat or sebaceous glands, thusneeds to be wet (or lip balm)

CheeksFUNCTION


200/308

FUNCTION Form side of moth

STRUCTURE Buccinator muscle

instrumental inswallowing, connects back

to pharyngeal constrictors

Palate Hard palate anterior


201/308

Maxilla Palatine

Soft palate is posteriorextension, soft tissue

Palatoglossal arch

(palate to tongue) Palatopharyngeal arch

(palate to pharynx) Tonsils between arches Uvula???

Jaws


202/308

FUNCTION

Hold teeth Occlude in chewing

STRUCTURE "

Upper jawmaxillary bone " Lower jaw--mandible "

Teeth Deciduous teeth milk

or baby teeth


203/308

or baby teeth Emerge 6 mos. 2 yrs. Replaced by permanent

teeth 6-12 yrs. Wisdom teeth (3rd

molar) erupts 17-25 yrsor remains in jaw

Key to healthy teethand gums:

Flossing Visiting dentist

regularly (every 6mos.) and starting atyoung age (3-4 yrs.)

Structure of individual tooth


204/308

Jaw muscles


205/308

Masseter, temporaliselevatemandible ( close jaw)

Medial pterygoidlateral (side-to-side) chewing

Lateral pterygoidtranslatesmandible anteriorly (part ofopening)

Digastric (not shown)depressesmandible ( opens jaw )

Chewing is circular motion

TongueFUNCTION Position food between teeth


206/308

Position food between teeth Form words in speechSTRUCTURE Intrinsic muscles (allow for

shape change with bers in various directions)

Extrinsic musclesattachtongue to skeleton Genioglossus hyoglossus

Salivary glands Intrinsic all over


207/308

Intrinsicall overmucous membranesof tongue, palate,lips, lining of cheek

Extrinsicsecretemore saliva wheneating (oranticipating) Parotid Submandibular sublingual

Saliva Moistens mouth Dissolves food to be tasted


208/308

Dissolves food to be tasted Wets and binds food Contains amylase to start starch digestion

(saltine to sugar experiment)

Contains bicarbonate to neutralize cavity-causingacids produced by bacteria Contains anti-bacterial and anti-viral enzymes

and cyanide-like compound to kill harmful

micro-organisms Contains proteins that stimulate growth of

benecial bacteria in the mouth


209/308


210/308

Descent of the larynx


211/308


212/308

Larynx and SingingFUNCTION Channel air out of trachea Vibrate to produce sound for speech/songSTRUCTURES External skeleton or frame (cartilage) Internal vocal cords and associated muscles

Skeleton of larynx


213/308

Cricothyroid ligament is usual site of emergencytracheotomy (feel on selfSURFACE ANATOMY)

M&M, Fig. 21.5


214/308


215/308

Identify the three pharyngeal constrictor muscles and their anterior attachments to bony/cartilaginous structures. Identify the three small longitudinal muscles of the pharynx.

Buccinator


216/308

Superior constrictor

Middle constrictor

Inferior constrictor

Pterygomandibularraphe

Stylopharyngeus

Cricopharyngeus

Superior constrictor

Middle constrictor

Inferior constrictor

Stylopharyngeus

Cricopharyngeus

Palatopharyngeus

Salpingopharyngeus

Identify the major cartilages of the larynx

Epiglottis

Hyoid

Hyoid

Epiglottis


217/308

Anterior view Sagittal SectionPosterior view

Thyroid cart.Thyroid cart.

Cricoid cart.

Arytenoidcart.

Arytenoidcart.

Cricoid cart.

Vocal Cord


218/308

Identify the role played by each of these muscles in the control of the controlof the size of the rima glottidis.

Arytenoid cart.Rima glottidis

Post. Crico-arytenoid Lat. Crico-arytenoid

Arytenoid cart


219/308

Thyroid cart.

Aryepiglottic fold

Vocal cord

Arytenoideus

Vocal cord

Thyroid cart.

Rima glottidis

Actions of intrinsic laryngeal muscles


220/308

Trace the course of nerves through the neck noting especially: the sensory and motor branchesof the cervical and brachial plexuses, their course and distribution in the neck and theirrelationship to major bony, muscular, or vascular landmarks in the region.

Great auricular n. Lesser occipital n.C1

Great auricular n.

Lesseroccipital

Hypoglossal n. (XII)


221/308

Ansa cervicalis

Hypoglossal n. (XII)

Accessory n. (XI)

Phrenic n.

Vagus n. (X)

C5

C6

C7

C8

T1

Dorsal scapular n.

Nn. to longus colli and scalenes

Long thoracic n.

Suprascapular n.

C2

C3

C4

C5

Phrenic n.

occ p tan.

Transversecervicalnn.

Ansa cervicalis

Supraclavicular nn.Accessory n. (XI)

Trace the course of nerves through the neck noting especially: theextension of the upper part of the sympathetic trunk into the neck region.


222/308

Sup. Cervical gang.

Cervicothoracicgang.

MiddleCervical gang.

Carotid plexus

Glossopharyngeal (IX)

Vagus (X)

C2

C1

C3

C4C5

C6C7

C8

Trace the flow of arterial blood from the aorta through the neck including vessels that passthrough the neck without branching and those that send branches to viscera and muscles of the neck.

Two main arteries are found in the neck: Subclavian and branches and Carotid


223/308

Subclavian

Vertebral

Thyrocervical

Transversecervical

Deep cervical

Suprascapular

Ascendingcervical

Inf. thyroid

Ext. Carotid

Common carotid

Omohyoid

Digastric Lingual

Sup. thyroidSup. laryngeal

Int.carotid

Ext. carotid

Ascendingpharyngeal

Supercial temporal

Maxillary

Facial

Post.auricular

Trace the pathways for venous drainage from the neck into the brachialveins.


224/308

Ext. jugularInt. jugular

Ant. jugular

Sup. thyroid

Middlethyroid

Inf. thyroid


225/308

f c

facial view palatal view


226/308

e

a = nasal septumb = inferior conchac = nasal fossad = anterior nasal spine

e = incisive foramenf = median palatalsuture

ba

d

c

facial view


227/308

Nasal septum


228/308

facial view


229/308

Nasal fossa

facial view


230/308

Anterior nasal spine

palatal view


231/308

Incisive foramen

palatal view


232/308

Median palatal suture


233/308

Soft tissue of the nose

aa


234/308

Red arrow points toperiapical lesion (post-endo).

b

e

db

Red arrows = lip line

d


235/308

g

Red arrow = mesiodens(supernumerary tooth)

f

Blue arrow = chronic periapical periodontitis.Tooth # 9 is non-vital(trauma) and needs endo.


236/308

Superior foramina of the nasopalatine canals (red arrows).These foramina lie in the oor of the nasal fossa. Thenasopalatine canals travel downward to join in the incisiveforamen.

b a

f


237/308

d

The red arrows point to anincisive canal cyst; the orangearrow identies the root of tooth # 7.

All the incisors are non-vital andhave periapical lesions. The purplearrows point to external resorption;the blue arrow identies internalresorption.


238/308

The red arrows point to the soft tissue of the nose. Thegreen arrows identify the lip line.

Maxillary Cuspid

a


239/308

a = oor of nasal fossa

b = maxillary sinus

c = lateral fossa

d = nose

d

c

b

a a

facial view


240/308

a = oor of nasal fossab = maxillary sinusc = lateral fossa

(a & b form inverted Y)

cb

c

b

facial view


241/308

Floor of nasal fossa (red arrows) and anterior border of maxillary sinus (blue arrows), forming the inverted(upside down) Y.

facial view


242/308

Lateral fossa. The radiolucency results from adepression above and posterior to the lateral incisor. Tohelp rule out pathology, look for an intact lamina durasurrounding the adjacent teeth.


243/308

Soft tissue of the noseRed arrows point to nasolabial fold. Alsonote the inverted Y.


244/308

The maxillary sinussurrounds the root of thecanine, which may bemisinterpreted as pathology.

The white arrows indicate theoor of the nasal fossa. Themaxillary sinus (red arrows) haspneumatized between the 2 nd premolar and rst molar


245/308

a b c

Maxillary Premolar


246/308

a = malar process

b = sinus septum

c = sinus recess

d = maxillary sinus

d

b b

facial view


247/308

a = malar process

b = sinus recessc = sinus septumd = maxillary sinus

a c d dca

facial view


248/308

Malar (zygomatic) process. U or j-shapedradiopacity, often superimposed over the roots of themolars, especially when using the bisecting-angletechnique. The red arrows dene the lower border of the zygomatic bone.

facial view


249/308

Sinus septum. This septum is composed of folds of cortical bone that arise from the oor and walls of the

maxillary sinus, extending several millimeters into thesinus. In rare cases, the septum completely divides thesinus into separate compartments.

facial view


250/308

Sinus recess. Increased area of radiolucency causedby outpocketing (localized expansion) of sinus wall.If superimposed over roots, may mimic pathology.


251/308


252/308


253/308

Pneumatization. Expansion of sinus wall intosurrounding bone, usually in areas where teethhave been lost prematurely. Increases with age.


254/308

g

d

efacial view

e

g


255/308

a

f

a = maxillary tuberosity* e = zygoma (dotted lines)b = coronoid process f = maxillary sinusc = hamular process g = sinus recessd = pterygoid plates

* image of impacted third molar superimposed

c

b

d

b

ac f

facial view


256/308

Maxillary Tuberosity. The rounded elevation locatedat the posterior aspect of both sides of the maxilla.Aids in the retention of dentures.

facial view


257/308

Coronoid process. A mandibular structure sometimesseen on the maxillary molar periapical lm when usingthe bisecting angle technique with nger retention (Themouth is opened wide, moving the coronoid down andforward). Note the supernumerary molar.

facial view


258/308

Hamular process (white arrows) and pterygoid plates(purple arrows). The hamular process is an extension of the

medial pterygoid plate of the sphenoid bone, positioned just posterior to the maxillary tuberosity.

facial view


259/308

Zygomatic (malar) bone/process/arch. Thezygomatic bone (white/black arrows) starts in the

anterior aspect with the zygomatic process (bluearrow), which has a U-shape. The zygomaticbone extends posteriorly into the zygomatic arch(green arrow).

facial view


260/308

Maxillary sinus. As seen in the above lm, the oor of the maxillarysinus ows around the roots of the maxillary molars and premolars.The walls of the sinus may become very thin. As a result, sinusitis mayput pressure on the superior alveolar nerves resulting in apparent

tooth pain, even though the tooth is perfectly healthy. Note coronoidprocess (green arrow), zygomatic bone (blue arrow), sinus septum(yellow arrow) and neurovascular canal (orange arrows).


261/308

The maxillary sinus is evidentanterior to the second molar(black arrows) but it disappearsposteriorly due to thesuperimposition of the zygomatic

bone. The orange arrows identify amucous retention cyst (retentionpseudocyst) within the sinus.

This lm shows the coronoidprocess (green arrow) and adistomolar (blue arrow) that haserupted ahead of the thirdmolar (red arrow). A

distomolar is a supernumerarytooth that erupts distal(posterior) to the other molars.


262/308

The zygomatic process (green arrows) is a prominent U-shaped radiopacity. Normally the zygomatic bone posterior tothis is very dense and radiopaque. In this patient, however, themaxillary sinus has expanded into the zygomatic bone andmakes the area more radiolucent (red arrows). The coronoidprocess (orange arrow), the pterygoid plates (blue arrows) andthe maxillary tuberosity (pink arrows) are also identied.


263/308

This lm shows the expansion of the borders of the maxillarysinus through pneumatization (red arrows). This expansionincreases with age and it may be accelerated as a result of chronicsinus infections. It is most commonly seen when the rst molar isextracted prematurely, as in the lm at right (the second and thirdmolars have migrated anteriorly to close the space). The coronoidprocess is seen in the lower left-hand corner of each lm. Thegreen arrow identies a sinus recess. Note the two distomolars inlm at right (blue arrows).

li l f

Mandibular Incisor


264/308

a. lingual foramen

b. genial tubercles

c. mental ridge

d. mental fossa

a b c

d

facial viewlingual view


265/308

b = genial tubercles

a = lingual foramen c = mental ridge

d = mental fossa

ab

cd

lingual view


266/308

Lingual foramen. Radiolucent hole in center of genial tubercles. Lingual nutrient vessels pass throughthis foramen.

lingual view


267/308

Genial tubercles. Radiopaque area in the midline, midwaybetween the inferior border of the mandible and the apices of the incisors. Serve as attachments for the genioglossus andgeniohyoid muscles. May have radiolucent hole in center(lingual foramen), but not on this lm. Note double rootedcanine (red arrows).

facial view


268/308

Mental ridge. These represent the raised portions of the mentalprotuberance on either side of the midline. More commonlyseen when using the bisecting angle technique, when the x-raybeam is directed at an upward angle through the ridges.

facial view


269/308

Mental fossa. This represents a depression on the labialaspect of the mandible overlying the roots of the incisors.The resulting radiolucency may be mistaken forpathology.


270/308

The radiolucent area abovecorresponds to the location of themental fossa. However, this slide

represents chronic periapicalperiodontitis; these teeth arenon-vital, due to trauma.

The orange arrows aboveidentify nutrient canals. Theyare most often seen in older

persons with thin bone, and inthose with high blood pressureor advanced periodontitis.

Mandibular Canine


271/308

a b

a = mental ridgeb = genial tubercles/

lingual foramenc = mental foramen

c


272/308

facial view


273/308

Mental ridge. The raised portions of the mentalprotuberance, sloping downward and backward fromthe midline.

lingual view


274/308

Lingual foramen/genial tubercles. (Seedescription under mandibular incisor above).

facial view


275/308

The red arrows identify the mandibular canal andthe blue arrow points to the mental foramen.

Mandibular Premolar


276/308

a = mylohyoid ridgeb = mandibular canalc = submandibular gland fossad = mental foramen

facial view lingual view

ad

d b


277/308

c

b = mandibular canald = mental foramen

a = mylohyoid ridge(internal oblique)

c = submandibular glandfossa

c

add b

lingual view


278/308

Mylohyoid (internal oblique) ridge. This radiopaque ridgeis the attachment for the mylohyoid muscle. The ridgeruns downward and forward from the third molar regionto the area of the premolars.

facial view


279/308

Mandibular canal. (Inferior alveolar canal). Runsdownward from the mandibular foramen to the mentalforamen, passing close to the roots of the molars. Moreeasily seen in the molar periapical.

lingual view


280/308

Submandibular gland fossa. The depression below themylohyoid ridge where the submandibular gland is

located. More obvious in the molar periapical lm.

facial view


281/308

Mental foramen. Usually located midway between theupper and lower borders of the body of the mandible, in

the area of the premolars. May mimic pathology if superimposed over the apex of one of the premolars.


282/308

The mental foramen (bluearrow) is adjacent to aperiapical lesion associated withtooth # 21 (red arrow). There isslight external resorption on #21.

The green arrow points to themental foramen. The yellow arrowidenties a periapical lesion on # 30.Note the overextension of the silverpoint in the distal root, the

perforation of the mesial root andthe amalgam protruding throughthe perforation from the pulpchamber.

Mandibular Molar


283/308

a = external oblique ridge

b = mylohyoid ridgec = mandibular canald = submandibular gland fossa

facial view lingual view

b

a

b


284/308

b

c

b

a = external oblique ridgec = mandibular canal

b = mylohyoid ridged = submandibular gland

fossa

dd

ab


285/308

c

dd

a = external oblique ridge

b = mylohyoid ridgec = mandibular canald = submandibular gland fossa

facial view


286/308

External oblique ridge. A continuation of the anteriorborder of the ramus, passing downward and forward onthe buccal side of the mandible. It appears as a distinct

radiopaque line which usually ends anteriorly in the areaof the rst molar. Serves as an attachment of thebuccinator muscle. (The red arrows point to the mylohyoidridge).

lingual view


287/308

Mylohyoid ridge (internal oblique). Located on the lingualsurface of the mandible, extending from the third molar

area to the premolar region. Serves as the attachment of the mylohyoid muscle.

facial view


288/308

Mandibular (inferior alveolar) canal. Arises at the mandibularforamen on the lingual side of the ramus and passes downwardand forward, moving from the lingual side of the mandible in thethird molar region to the buccal side of the mandible in thepremolar region. Contains the inferior alveolar nerve andvessels.

lingual view


289/308

Submandibular gland fossa. A depression on the lingualside of the mandible below the mylohyoid ridge. Thesubmandibular gland is located in this region. Due to thethinness of bone, the trabecular pattern of the bone is very

sparse and results in the area being very radiolucent. Thefact that it occurs bilaterally helps to differentiate it frompathology.


290/308

The external oblique ridge (red arrows) and themylohyoid ridge (blue arrows) usually run parallel witheach other, with the external oblique ridge always beinghigher on the lm.


291/308

The mandibular canal (red arrows identify inferior border of canal) usually runs very close to the roots of the molars, especially the third molar. This can be a problem whenextracting these teeth. Note the extreme dilaceration (curving) of the roots of the third molar (green arrow) in the lm at left. Thelm at right shows kissing impactions located at the superiorborder of the canal.

Slide # 1


292/308

A. The red arrows identify the ?

Slide # 1


293/308

A. Floor of nasal cavity

Slide # 2


294/308

A. The red arrow points to the ?

B. The white arrows identify the ?C. The blue arrow points to the ?

D. The yellow arrow identifies the ?

Slide # 2


295/308

A. Coronoid processB. B. Maxillary sinus

(pneumatized into maxillarytuberosity)

C. Sinus septumD. Zygomatic process

Slide # 3


296/308

A. The small radioluceny identified bythe green arrow is the ?

Slide # 3


297/308

A. Lingual foramen


298/308

Slide # 4


299/308

A. Mylohyoid ridgeB. Submandibular gland fossa

Slide # 5


300/308

A. The yellow arrows point to the ?

B. The red arrows identify the ?

Slide # 5


301/308

A. Zygomatic processB. Maxillary sinus

Slide # 6


302/308

A. The red arrow points to the ?

B. The orange arrow points to the ?

C. The blue arrows point to theradiolucent line known as the ?

Slide # 6


303/308

A. Inferior concha

B. Nasal septumC. Median palatal suture

Slide # 7


304/308

A. The red arrows point to the ?

Slide # 7


305/308

A. Mental ridge

Slide # 8


306/308

A. The red arrows identify the ?B. What is the name of the radiolucent

area surrounding the canal?

Slide # 8


307/308

A. Mandibular canalB. Submandibular gland fossa

References

-Netter atlas of human anatomy-Netter neuro-anatomy-Netter anatomy of head and neck


308/308

-Greys anatomy-Snells Human anatomy-Robbinss anatomy and pathology

-Contemporary oral and maxillofacial surgeryO l di l i i l d i i

Maxillofacial Head

Documents

Transcript of Maxillofacial Head