Frontal Bone

Corona suture

Glabella- space b/t eyebrows and above the nose

Orbital Roof

Posterial/Anterial Ethmoid Foramina

Supraorbital Notch/Foramen

Groove for superior sagittal sinus

Frontal crest

Groove of Ant. Menigeal a/v

Foramen cecum- Emissary veins

Superior/Inferior temporal lines (fascia and tempralis muscle)

Groove of anterior Meningeal a/v

Temporomastoid Joint (TMJ)

Synovial joint

Articulate b/w condyle of mandible and squamous portion of the temporal bone

2 distinct joints

Articular disc (meniscus)

Capsule of the joint

Ligaments of joint

1. Lateral(temporomandibular) ligament
2. Sphenomandibular ligament
3. Stylomaindibular ligament

Nerve supply: Auriculotemporal n (CN V3)

Movements: Depression, Elevation, Protrusion, Retraction, Lateral movement

TMJ joint capsule

From the neck of condyle around the articular margin

Attached anteriorly to the articular eminence

Attached posteriorly to the squamotypanic fissure posteriorly

Ariticular disc of TMJ

Fibrous - molded to the boy joint surfaces

Its margin merge with the join capsule

Separate avascular anterior and posterior band 

Anteriorly: attached to lateral pterygoid muscle

Posteriorly: disc becomes bilaminar

Superiorly: attached to anterior margin of the squmotympanic fissure

Inferiorly: posterior margin of condyle

Lateral ligament

(Temporalmandibular ligament)

Lower border of zygomatic process of temporal bone

Posterior border of condylar neck and ramus of the mandible

Sphenomandibular ligament

Spine of sphenoid 

Lingua of mandible

Stylomandibular ligament

Styloid process of temporal bone

Angle and posterior border of ramus of the mandible

Depression of TMJ

1. Lateral pterygoid muscle
2. Suprahyoid muscle
3. Infrahyoid muscle 

Elevation of TMJ

1. Temporalis
2. Masseter
3. Medial pterygoid 

Protrusion of TMJ

1. Lateral pterygoid muscle
2. Medial pterygoid muscle
3. Masseter

Retraction of TMJ

1. Temporalis
2. Masseter

Lateral movement of TMJ

1. Temporalis (on the same side)
2. Medial/lateral pterygoid (opposite side)
3. Masseter (same side)

Olfactory N

Special sensory

O: Olfactory cells

E: foramina in the cribrifrom plate of the ethmoid

Smell from nasal mucosal (in roof of each naal cavity, and superior sides of nasal septum and superior concha)

OPTIC NERVE

CN II

Special Sensory

O: Retina (ganglion cells)

E: Optic canal

Vision from retina

OCULOMOTOR NERVE

CN III

Somatic motor

O- midbrain

E- Superior Orbital Fissure

Motor to supply inf./med. Rectus, Inf. Oblique/ Levator palpebrae superioris muscle 

Raises upper eyelid

Turns eyeball sup./Inf/medially

Visceral motor

O- preganglionic (midbrain)

E- superior orbital fissure

Parasympathetic innervation to sphincter pupillae, ciliary muscle

Constrict pupil/ accommodate lens of eyes

Run in lateral wall of the cavernous sinus

Lesion --> ptosis (dropping) of upper eyelid

               No pupilillary reflexes

               Dilation of the pupil caused by

               interruption of the Parasympathetic

               fibers to the iris

               Eyeball abduted with slight inferior

               direction 

               No accommodation of the lens b/c of 

               paralysis of the ciliary muscle

Trochlear nerve

CN IV

Somatic Motor

O: midbrain

E: superior orbital fissure

Motor to the superior oblique that assists in turning of the eye inferoiolaterally

emerges from the dorsal side of the midbrain and pases anteriorly in the lateral wall of the cavernous sinus

Lesion --> diploplia  (double vision)

Trigeminal nerve 

CN V

3 branches

Mixed nerve

Opthalamic Nerve

CN V1

General sensory

O: trigeminal ganglion

E: superior orbital fissure

Sensation from the cornea, skin of forehead, scalp, eyelids, nose and mucosa of nasal cavity and paranasal sinuses

Maxillary nerve

CN V2

General sensory

O: trigeminal ganglion

E: foramen rotundum

Sensation from face over maxilla, including upper lip, maxillary teeth, mucosa of nose, maxillary sinuses and palate

Mandibular Nerve

CN V3

Mixed

Branchial motor

O: pons

E: foramen ovale

Motor to :

Masseter, temporalis, medial/lateral pterygoid, Mylohyoid, Anterior belly of digastric, tensor veli palatini, and tensor tympani

General sensory (same O/E)

Sensation from the skin over mandible, including lower lip and side of head

Mandibular teeth

TMJ

mucosa of mouth and anteiro 2/3 of tongue

Abducent nerve

CN VI

Facial Nerve 

CN VII

Branchial Motor

O:pons

E: IAM, facial canal, and stylomastoid foramen

Motor to muscles of facial expression and scalp

Supplies stapedius of middle ear

Styloid and posterior belly of digastric

Special sensory

O: Geniculate ganglion

E: IAM, facial canal and stylomastoid foramen

Taste from anterior 2/3 of tongue, (floor of mouth and palate)

General sensory - Sensation from skin of EAM

Visceral motor

O: preganglionic- pons

    postganglionic - pterygopalatne ganglion and                              submandibular ganglion

E: IAM, facial canal and stylomastoid foramen

Parasympathetic innervation to submandibular and sublingual salivary glands, lacrimal gland and glands of nose and palate

Vestibulocochlear Nerve 

CN VIII

Special sensory - Hearing

2 parts

O: Vesibular ganglion - equlibrium

E: IAM

veistublar sensation from semicircular ducts, utricle and saccule related to position and movement of the head

O: Sprial ganglion 

E: IAM

Hearing from spiral organ

Glossopharygneal nerve 

CN IX

Mixed nerve

Branchial Motor

O: medulla

E: Jugular foramen

Motor to stylopharyngeus that assists with swallowing

Viseral motor

O: pre - medulla post: Otic ganglion

E: Jugular foramen

Parasympathetic innervation to parotid gland

Viscery sensory

O: superior ganglion

E: Jugular foramen

Visceral sensation form parotid gland, carotid body and sinus

Special sensory

O:Inferior ganglion

E: jugular foramen

Taste from posterior 1/3 of tongue

General sensory (same as above)- cutaneous sensation from external ear

VAGUS NERVE

CNX

Accessory nerve 

CN XI

Cranial root - Somatic motor

O: Medulla

E: Jugular foramen

motor to striated muscles of soft palate, pharynx and larynx via fibers that join CN X

Spinal root- Branchial motor

O: spinal cord

E: jugular foramen

Motor to SCM and trapezius

Hypoglossal nerve

CN XII

Somatic motor

O- Medulla

E- hypoglossal canal

Motor muscle to tongue 

Pterygoid Fovea

[image]

Upper most medial size of the ramus

Insertion site of the lateral pterygoid muscle

Mandibular notch 

[image]

Surrmounted by two processes : coronoid proces and condyloid process

Passage for :

1. Masseter nerve (V3) --> Masseter muscle
2. Massteric a. (Max a.)- deep to tendon of temporalis ( anatomeses with maxillary a. (Facial) and transverse facial a.
3. Masseteric v. 

Antegonial notch

[image]

Depression along jawline - groove for facial a. 

Nasal septum 

[image]

Perpendicular plate of ethmoid

Vomer

Cartilage of septum

Crest of maxillary bone

Crest of palatine bone

Zygomaticofacial foramen

[image]

On zygomatic bone (Malar surface)

Passage for zygomaticofacial n (V2) --> skin of malar

Cross inferolateral angel of orbit and leave zygomatic bone through zygomaticofacial foramen and pierced through orbicularis oculi

Plexus with zygomatic branch of facial n (CN VII) and inferior palpebral branches of maxillary n. 

Conchae

[image]

Superior/Middle conchae = ethomoid bone

Inferior conchae - individual bone

Rough with holes due to high vasculation

Conchea + Mucosa = Turbinate

Lacrimal groove/ Sulcus

[image]

Nasal surface of maxilla body --> Nasal canal

Open into inferior meatus of nose

Transmit nasolacrimal duct 

Pterygoid canal

[image]

Runs through the medial pterygoid plate of the sphenoid bone to the back wall of the pterygopalatine fossa

Contains :

1. Greater superficial petrosal nerve/a

Greater Superficial Petrosal N. 

[image]

Emerges through hiatus of facial canal-->medially along anterior slop of petrous temporal bone--> superior aspect of cartilage (over foramen lacerum) --> joined by deep perosal nerve --> Make right angle--> enter pterygoid canal --> pterygoidpalatine ganglion

Function: 

-gustatory (taste)

-parasympathetic fibres.

Postganglionic parasympathetic fibres from pterygopalatine ganglion supply lacrimal gland and the mucosal glands of the nose, palate, and pharynx. The gustatory fibres do not relay in the ganglion and are distributed to the palate.

Facial Canal

[image]

A Z-shaped canal running through the temporal bone from the internal acoustic meatus to the stylomastoid foramen

It is located within the middle ear region

it is divided into three main segments:

1. the labyrinthine
2. the tympanic
3. the mastoidal segmen

Greater petrosal n (CN VII) at geniculate ganglion --> join deep petrosal n at foramen lacerum --> form nerve of pterygoid canal --> pterygoid canal --> pterygoidpalatine fossa--> post synapses with parasympathetic fiber --> innervates lacrimal glands (via Zygomatic branch of V2 + lacrimal nerve of V1)

Chorda tympani n (superior to stylomastoid foramen)--> cross tymapnic cavity--> petrotympanic fissure--> join lingual nerve  (V3)(in infratemporal fossa) --> parasympathetic of chorda tympanic synapse in submandibular ganglion--> post syn follow arteries --> Glands

Chorda tympani

[image]

Emerges through petrotympanic fissure

Special sense : Join lingua nerve -- taste from anterior 2/3 of tongue

Preganglionic parasympathetics  --> submandibular and sublingual glands (synapses in submandibular ganglion)

Superior orbital fissure

[image]

Structures that passed through it:

• superior and inferior divisions of oculomotor nerve (III)
• trochlear nerve (IV)
• lacrimal, frontal and nasociliary branches of ophthalmic nerve (V₁)
• abducens nerve (VI)
• superior and inferior divisions of ophthalmic vein
• sympathetic fibers from cavernous plexus

Rochon-Duvigneaud's syndrome is a neurological disorder that results if the superior orbital fissure is fractured. Involvement of the cranial nerves that pass through the superior orbital fissure may lead to diplopia, paralysisof extraocular motions, exophthalmos, and ptosis. Blindness or loss of vision indicates involvement of the orbital apex, which is more serious, requiring urgent surgical intervention.

Foramen rotundum

[image]

Circular hole in the sphenoid bone that connects the middle cranial fossa and the pterygopalatine fossa

Maxillary nerve passes through and exits the skull via the pterygopalatine fossa and the foramen rotundum

Foramen ovale

[image]

Anterior part of the sphenoid bone, posteriolateral to the foramen rotundum

Contains: 

• Mandibular nerve (V₃) 
• Accessory meningeal artery (small meningeal or parvidural branch, sometimes derived from the middle meningeal artery)
• Lesser petrosal nerve of (CN IX) (note: the lesser superficial petrosal nerve sometimes passes through a special canal (canaliculus innominatus of Arnold), situated medial to theforamen spinosum)
• Emissary veins (from the cavernous sinus to the pterygoid plexus)

• The otic ganglion is situated directly under the foramen, but is also transmitted through the foramen ovale.

Foramen spinosum

• middle meningeal artery
• a recurrent branch, the nervus spinosus, from the mandibular nerve (V₃)
• the posterior trunk of the middle meningeal vein

Foramen lacerum

Triangular hole in the base of the skull located at the base of the medial pterygoid plate.

Structures associated with the foramen are

1. the internal carotid artery, which enters posteriorly and emerges superiorly
2. the greater petrosal nerve and the deep petrosal nerve (which join to form the nerve of the pterygoid canal)
3. a meningeal branch of the ascending pharyngeal artery (a branch of the external carotid artery)
4. emissary veins, which link the cavernous sinus and pterygoid venous plexus.

IAM

[image]

Does not transmit sound waves.

It instead transmits

1. the facial (travels through the facial canal, eventually exiting the skull at the stylomastoid foramen) CN VII
2. the vestibulocochlear nerves CN VIII
3. labyrinthine artery(an internal auditory branch of the basilar artery) 

Stylomastoid foramen

Petrotympanic fissure

[image]

fissure in the temporal bone that runs from the temporomandibular joint to the tympanic cavity

passage to the 

1. anterior tympanic a. branch of the internal maxillary artery.

2. communications of cranial nerves chorda tympani VII and lingual nerve of CN IX to the infratemporal fossa

Attachment to the lateral pterygoid muscle

Its medial surface forms part of the pterygoid fossa, and gives attachment to the medial pterygoid muscle.

Medial pterygoid plate

Articular tubercle

[image]

Anterior limit of TMJ

articulate withe the mandible

anterior root of the posterior end of the outer surface of the Squama temporalis, continuous with the lower border, is short but broad and strong

 anchor point for several muscles associated with the tongue and larynx.

• Its proximal part (tympanohyal) is ensheathed by the vaginal process of the tympanic portion.
• Its distal part (stylohyal) gives attachment to the following:
  • stylohyoid ligament
  • stylomandibular ligament
  • styloglossus muscle (innervated by the hypoglossal nerve)
  • stylohyoid muscle (innervated by the facial nerve)
  • stylopharyngeus muscle (innervated by the glossopharyngeal nerve)

attachment of the 

1. Digastric
2. Sternocleidomastoid
3. Splenius capitis
4. Longissimus capitis muscles

Intraorbital n (V2) [sensation to lower eyelid, upper lip and vestibule]  

artery

vein

Mental n (V3) /a/v 

- divides beneath the Depressor anguli oris muscle into three branches:

• one descends to the skin of the chin.
• two ascend to the skin and mucous membrane of the lower lip.

Contains:

1. zygomatic branch of V2 Maxillary nerve
2. Sphenopalatine ganglion

It is formed by the sphenoid bone and maxilla.

formed by the zygomatic process of temporal bone and the temporal process of the zygomatic bone ( the two being united by an oblique suture)

Tendon of the Temporalis passes medial to the arch to gain insertion into the coronoid process of the mandible

The upper border of the arch gives attachment to the temporal fascia; the lower border and medial surface give origin to the Masseter.

It is bounded by the following structures:

• anteriorly, by the infratemporal surface of the maxilla and the ridge which descends from itszygomatic process

• posteriorly, by the articular tubercle of the temporal and the spinal angularis of the sphenoid

• superiorly, by the greater wing of the sphenoid below the infratemporal crest, and by the under surface of the temporal squama

• inferiorly, by the alveolar border of the maxilla

• medially, by the lateral pterygoid plate

• laterally, by the ramus of mandible

it has NO FLOOR

Muscles

• the lower part of the Temporalis muscle
• lateral and medial pterygoid muscles

[edit]Vessels

The internal maxillary vessels, consisting of the maxillary artery originating from the external carotid artery and its branches.

Internal maxillary branches found within the infratemporal fossa including the

• middle meningeal artery
• inferior alveolar artery
• deep temporal artery
• buccal artery

[edit]Veins

• pterygoid venous plexus

[edit]Nerves

Mandibular nerve, inferior alveolar nerve, lingual nerve, buccal nerve, chorda tympani nerve, and otic ganglion.^[1]

[edit]Mandibular nerve

• Mandibular nerve which is the third branch of the trigeminal nerve (CN V₃), also known as the "inferior maxillary nerve" or nervus mandibularis, enters infratemporal fossa from middle cranial fossa through foramen ovale.

Motor branches:

• masseteric nerve
• deep temporal nerve
• lateral pterygoid nerve and medial pterygoid nerve

vertical, and descends at right angles from the medial end of the inferior orbital fissure; it is a triangular interval, formed by the divergence of the maxilla from the pterygoid process of the sphenoid.

It connects the infratemporal with the pterygopalatine fossa, and transmits the terminal part of the maxillary artery. Alveolar branches of the maxillary nerve go from the pterygopalatine fossa to the infratemporal region via this fissure.