Dr. Ahmed Fathalla Ibrahim

TEMPORAL FOSSATEMPORAL FOSSA

TEMPORAL FOSSATEMPORAL FOSSA

INFRATEMPORAL FOSSAINFRATEMPORAL FOSSA

TEMPORAL FOSSATEMPORAL FOSSA

BOUNDARIES:BOUNDARIES:

• Anterior:Anterior: Zygomatic process of frontal bone + zygomatic bone

• Superior & Posterior:Superior & Posterior: Temporal lines

• Inferior:Inferior: Zygomatic arch

TEMPORAL FOSSATEMPORAL FOSSA

CONTENTS:CONTENTS:

1. Temporalis muscle

2. Deep temporal nerve & vessels

3. Superficial temporal vessels

4. Auriculotemporal nerve

INFRATEMPORAL FOSSAINFRATEMPORAL FOSSA

BOUNDARIES:BOUNDARIES:

• Superficial (lateral):Superficial (lateral): Ramus of mandible

• Deep (medial):Deep (medial): Lateral pterygoid plate

• Superior:Superior: Infratemporal surface of greater wing of sphenoid

• Anterior:Anterior: Tuberosity of maxilla

INFRATEMPORAL FOSSAINFRATEMPORAL FOSSACOMMUNICATIONS:COMMUNICATIONS:

1.1. With temporal fossa: With temporal fossa: through a gap deep to zygomatic arch

2.2. With cranial cavity: With cranial cavity: through foramen foramen ovale, foramen spinosum, foramen ovale, foramen spinosum, foramen lacerumlacerum

3.3. With orbit: With orbit: through inferior orbital fissureinferior orbital fissure

4.4. With pterygopalatine fossa: With pterygopalatine fossa: through pterygomaxillary fissurepterygomaxillary fissure

INFRATEMPORAL FOSSAINFRATEMPORAL FOSSA

CONTENTS:CONTENTS:1. Lateral & medial pterygoid muscles2. Mandibular nerve & its branches3. A part of maxillary nerve & 2 of its

branches4. Otic ganglion5. Chorda tympani6. A part of maxillary artery & 2 of its

branches7. Pterygoid plexus of veins

THE MANDIBLETHE MANDIBLE

TEMPOROMANDIBULAR JOINTTEMPOROMANDIBULAR JOINT

TEMPOROMANDIBULAR JOINTTEMPOROMANDIBULAR JOINT

• TYPE: TYPE: synovial, condylar variety• ARTICULAR SURFACES:ARTICULAR SURFACES:

1.1. Upper: Upper: mandibular fossa + articular tubercle

2.2. Lower: Lower: head of mandible• CAPSULE: CAPSULE: attached to:

1. margins of mandibular fossa & articular tubercle

2. Neck of mandible

TEMPOROMANDIBULAR JOINTTEMPOROMANDIBULAR JOINT

• JOINT CAVITY: JOINT CAVITY: divided into upper & lower parts by an articular disc

• ARTICULAR DISC: ARTICULAR DISC: a plate of fibrocartilage with a concavoconvex upper surface and a concave lower surface

• LIGAMENTSLIGAMENTS1.1. Lateral temporomandibular: Lateral temporomandibular: from tubercle on the

root of zygoma to lateral surface of neck of mandible

2.2. Sphenomandibular: Sphenomandibular: from spine of sphenoid to lingula of mandible

3.3. StylomandibularStylomandibular

TEMPOROMANDIBULAR JOINTTEMPOROMANDIBULAR JOINT• NERVE SUPPLY: NERVE SUPPLY: auriculotemporal• ARTERIAL SUPPLY: ARTERIAL SUPPLY: maxillary• MOVEMENTS: MOVEMENTS: elevation, depression,

protrusion, retraction, chewing (side-to- side) movements

• RELATIONSRELATIONS1.1. Anterior: Anterior: mandibular notch, masseteric nerve &

vessels2.2. Posterior: Posterior: tympanic plate of temporal bone3.3. Lateral: Lateral: Parotid gland4.4. Medial: Medial: auriculotemporal nerve, maxillary artery

MUSCLES OF MASTICATIONMUSCLES OF MASTICATION1.1. TEMPORALISTEMPORALIS2.2. MASSETERMASSETER3.3. LATERAL PTERYGOIDLATERAL PTERYGOID4.4. MEDIAL PTERYGOIDMEDIAL PTERYGOID• They are They are derived fromderived from mesoderm of 1 mesoderm of 1stst

branchial archbranchial arch• They They originate from originate from temporal or temporal or

infratemporal fossainfratemporal fossa• They are They are inserted intoinserted into ramus of mandible ramus of mandible• They are They are suppliedsupplied, through their deep , through their deep

surfaces by branches of mandibular nervesurfaces by branches of mandibular nerve• They They act onact on temporomandibular joint temporomandibular joint

MUSCLES OF MASTICATIONMUSCLES OF MASTICATION

MUSCLES OF MASTICATIONMUSCLES OF MASTICATION

TEMPORALISTEMPORALIS

• ORIGIN: ORIGIN: floor of temporal fossa & deep surface of temporal fasica

• INSERTION: INSERTION: the tendon passes deep to zygomatic arch to be inserted to all coronoid process (except its lateral surface)

• NERVE SUPPLY: NERVE SUPPLY: 2 deep temporal nerves from anterior divisionanterior division of mandibular nerve

• ACTION: ACTION: 1. Elevation of mandible2. Its posterior fibers retract the mandible

MASSETERMASSETER

• ORIGIN: ORIGIN: lower border & inner surface of zygomatic arch

• INSERTION: INSERTION: lateral surface of ramus of mandible• NERVE SUPPLY: NERVE SUPPLY: from anterior divisionanterior division of

mandibular nerve• ACTION: ACTION: 1. Elevation of mandible2. Protrusion of mandible (when muscles on both

sides act together)3. Side-to-side movement (when muscles on both

sides act alternatively)

LATERAL PTERYGOIDLATERAL PTERYGOID• ORIGIN:ORIGIN:1.1. Upper head: Upper head: infratemporal surface of greater wing of

sphenoid2.2. Lower head: Lower head: lateral surfacelateral surface of lateral pterygoid plate• INSERTION: INSERTION: pterygoid fovea (in front of neck of

mandible) + capsule & articular disc of TMJ• NERVE SUPPLY: NERVE SUPPLY: from anterior divisionanterior division of mandibular

nerve• ACTION:ACTION:1. Pulls the condylar process forward to depress the

mandible 2. Protrusion of mandible (when muscles on both sides

act together)3. Side-to-side movement (when muscles on both sides

act alternatively)

MEDIAL PTERYGOIDMEDIAL PTERYGOID• ORIGIN:ORIGIN:1.1. Superficial head: Superficial head: tuberosity of maxilla2.2. Deep head: Deep head: medial surfacemedial surface of lateral pterygoid plate • INSERTION: INSERTION: medial surface of ramus & angle of

mandible• NERVE SUPPLY: NERVE SUPPLY: from trunktrunk of mandibular nerve• ACTION: ACTION: 1. Elevation of mandible2. Protrusion of mandible (when muscles on both

sides act together)3. Side-to-side movement (when muscles on both

sides act alternatively)

ALL MUSCLES OF ALL MUSCLES OF MASTICATIONMASTICATION

Elevate mandible Elevate mandible EXCEPTEXCEPT• Lateral pterygoidLateral pterygoid

Protrude mandible Protrude mandible EXCEPTEXCEPT• TemporalisTemporalis

Are supplied by anterior division of Are supplied by anterior division of mandibular nerve mandibular nerve EXCEPTEXCEPT

• Medial pterygoidMedial pterygoid

MANDIBULAR NERVEMANDIBULAR NERVE

INFRATEMPORAL FOSSAINFRATEMPORAL FOSSA

MANDIBULAR NERVEMANDIBULAR NERVE• COMPOSITION:COMPOSITION:• Formed of 2 roots2 roots: motor & sensorymotor & sensory

• ORIGIN: ORIGIN: • Sensory root:Sensory root: peripheral processes

of cells of trigeminal ganglion in the middle cranial fossa

• Motor root:Motor root: axons of cells of motor nucleus of trigeminal nerve in pons

MANDIBULAR NERVEMANDIBULAR NERVE• COURSE:COURSE:

• Both roots emerge separatelyseparately through foramen ovaleforamen ovale to infratemporal fossainfratemporal fossa

• The 2 roots unite, belowunite, below foramen ovale

• The nerve soon dividesdivides into a small a small anterior & a large posterior divisionanterior & a large posterior division

MANDIBULAR NERVEMANDIBULAR NERVE

• RELATIONS:RELATIONS:

1.1. Superficial: Superficial: lateral pterygoid

2.2. Deep: Deep: otic ganglion

3.3. Posterior: Posterior: middle meningeal artery

BRANCHES FROM TRUNKBRANCHES FROM TRUNKOF MANDIBULAR NERVEOF MANDIBULAR NERVE

• One motor:One motor: Nerve to medial pterygoid:medial pterygoid: supplies medial pterygoid & gives off 2 branches that pass through otic ganglion (without relay) & supply tensor palatitensor palati & tensor tympani tensor tympani musclesmuscles

• One sensory:One sensory: meningeal branch meningeal branch (nervus spinosus) (nervus spinosus) passing through foramen spinosum to supply meninges of middle cranial fossa

BRANCHES FROM ANTERIOR BRANCHES FROM ANTERIOR DIVISION OF MANDIBULAR NERVEDIVISION OF MANDIBULAR NERVE

Four branchesFour branchesThree motor:Three motor:• Masseteric nerve:Masseteric nerve: emerges through upper

border of lateral pterygoid & turns along mandibular notch to reach masseter

• Deep temporal nerves:Deep temporal nerves: emerge through upper border of lateral pterygoid

• Nerve to lateral pterygoidNerve to lateral pterygoidOne sensory:One sensory:• Buccal nerve: Buccal nerve: emerges between the 2 heads

of lateral pterygoid, supplies skin & mucous membrane overlying buccinator

BRANCHES FROM POSTERIOR BRANCHES FROM POSTERIOR DIVISION OF MANDIBULAR NERVEDIVISION OF MANDIBULAR NERVE

Four branchesFour branchesThree sensory:Three sensory:Auriculotemporal nerve: Auriculotemporal nerve: • Arises by 2 roots encircling middle

meningeal artery• Runs backward, deep to neck of mandible• Gives sensory branchessensory branches to skin of auricle,

temple, TMJ & parotid gland• Carries postganglionic parasympathetic postganglionic parasympathetic

secretomotorsecretomotor fibers from otic ganglion to parotid gland

BRANCHES FROM POSTERIOR BRANCHES FROM POSTERIOR DIVISION OF MANDIBULAR NERVEDIVISION OF MANDIBULAR NERVE

Lingual nerve:Lingual nerve:• Emerges through lower border of lateral

pterygoid then superficial to medial pterygoid• Joins chorda tympani• Runs just below 3rd molar tooth (dangerous dangerous

positionposition because it is only covered by muscous membrane)

• Runs superficial to hyoglossus & is connected to submandibular ganglion by 2 roots

• Carries general sensations from anterior 2/3 of tongue

BRANCHES FROM POSTERIOR BRANCHES FROM POSTERIOR DIVISION OF MANDIBULAR NERVEDIVISION OF MANDIBULAR NERVE

Inferior alveolar nerve:Inferior alveolar nerve:• Emerges through lower border of

lateral pterygoid then superficial to medial pterygoid, behind lingual nerve

• Passes through mandibular foramen & canal to supply lower teeth

• Emerges through mental foramen as mental nervemental nerve supplying skin of lower lip & chin

BRANCHES FROM POSTERIOR BRANCHES FROM POSTERIOR DIVISION OF MANDIBULAR NERVEDIVISION OF MANDIBULAR NERVE

One motor:One motor:

Mylohyoid nerve:Mylohyoid nerve:

• A branch of inferior alveolar nerve just above mandibular foramen

• Passes in mylohyoid groove of mandible

• Supplies mylohyoid & anterior belly of mylohyoid & anterior belly of digastric musclesdigastric muscles

RELATIONS OF LATERAL RELATIONS OF LATERAL PTERYGOIDPTERYGOID

RELATIONS OF LATERAL RELATIONS OF LATERAL PTERYGOIDPTERYGOID

• Superficial: Superficial: temporalis, masseter, ramus of mandible, maxillary artery, buccal nerve

• Deep: Deep: medial pterygoid, mandibular nerve, middle meningeal artery, otic ganglion

• Emerging through its upper border: Emerging through its upper border: deep temporal & masseteric nerves

• Emerging through its lower border: Emerging through its lower border: lingual & inferior alveolar nerves + maxillary artery

• Emerging between its 2 heads: Emerging between its 2 heads: buccal nerve, maxillary artery