Temporal & Infratemporal Region

1. Temporal & Infratemporal Regions -I
Dr. Prabhakar Yadav
Associate Professor
Department of Human Anatomy
B.P. Koirala Institute of Health Sciences

2. Teporal Fossa:
Boundaries:
Anterior: Zygomatic & Frontal bones
Posterior: Inferior temporal line &
supramastoid crest
Superior: Superior temporal line
Inferior: Zygomatic arch
Floor: Parts of frontal, Parietal, Temporal &
greater wing of Sphenoid
Pterion: lies in anterior part of floor where
frontal, parietal, squamous temporal and
greater wing of sphenoid meet at an H-shaped
suture.
Zygomatic arch: formed
Anteriorly by-- Temporal process of zygomatic bone &
Posteriorly by-- Zygomatic process or zygoma of
temporal bone.

3. Contents:
• Temporal fascia
•Temporalis muscle
( attached to floor & inferior
temporal line)
•Middle temporal artery ( branch of
superficial temporal art.)
•Zygomaticotemopral nerve &
artery
•Deep temporal nerve
•Deep temporal artery
•Deep temporal artery
•Deep temporal nerve
Zygomaticotemopral nerve
Middle temporal artery

4. Infratemporal fossa: Lies below the skull, behind the
body of maxilla & lateral to lateral pterygoid plate.
Boundaries:
•Anterior: Posterior surface of body of maxilla &
medial surface of Zygomatic bone.
•Roof: Infra temporal surface of greater wing of
sphenoid.
•Medial: Lateral pterygoid plate & pyramidal process
of palatine bone
•Lateral: Ramus of mandible
• Floor & posterior wall: Open
Temporal fossa communicates with infratemporal
fossa through a gap deep to zygomatic arch.

5. Contents:
1. Lateral pterygoid muscle; Medial pterygoid muscle
2. Mandibular nerve & its branches
3. Maxillary nerve with post. Superior alveolar nerve
4. Chorda tympani nerve
5. 1st & 2nd part of maxillary artery with their branches
6. Posterior superior alveolar artery( br. Of 3rd part of maxillary artery)
7. Accompanying veins.

6. MUSCLES OF MASTICATION:
Masseter, Temporalis, Lateral & Medial pterygoid
develop from first branchial arch,-supplied
by mandibular nerve
Temporalis:
Origin: (a)Temporal fossa
(b) Temporal Fascia
Fibres pass through gap deep to zygomatic arch
Insertion:
(a) Margins and deep surface of coronoid process
(b) Anterior border of ramus of mandible
Nerve supply: Two deep temporal nerve- branches
from anterior division of mandibular nerve
Actions: (a) Elevates mandible (b) Posterior fibres
retract the protruded mandible (c) Helps in side
to side grinding movement

7. Masseter:
Origin:
(a) Superficial ayer- Anterior 2/3 of lower border of
zygomatic arch & adjoining zygomatic process of
maxilla
(b) Middle layer: posterior 1/3rd of lower border of
zygomatic arch
(c) Deep layer: from deep surface of zygomatic arch
Insertion:
(a) superficial layer: lower part of lateral surface of
ramus of mandible
(b) Middle layer: central part of ramus of mandible
(c )Deep layer: upper part of the ramus of mandible &
coronoid process
Nerve supply: Masseteric Nerve
Action:
•Elevates mandible to close mouth
• superficial fibres - protrusion

8. Lateral Pterygoid:
Origin:
upper (small) head: infratemporal surface & crest of
greater wing of sphenoid
Lower (large) head: lateral surface of lateral pterygoid
plate
Insertion:
Pterygoid fovea, Articular disc & capsule of
temporomandibular joint.
Nerve supply: nerve to latral pterygoid- branch of
anterior division of mandibular nerve.
Actions
1. Lateral pterygoids of two sides depress the mandible
2. Lateral and medial pterygoid muscles of two sides acting together protrude the mandible.
3. Lateral and medial pterygoid muscles of the two sides contract alternately to produce side-to-side
movements of the lower jaw as in chewing.

9. Medial Pterygoid:
Origin:
Superficial (small) head: Maxillary tuberosity & lateral
surface of pyramidal process of palatine bone
Deep (large) head: Medial surface of lateral pterygoid
plate & pyramidal process of palatine bone.
Insertion: Roughened area on posteroinferior part of
medial surface & angle of ramus of mandible.
Nerve supply: nerve to medial pterygoid
Actions
1.Medial pterygoids of two sides elevates mandible
2.Acting with lateral pterygoids protrude mandible
3. Lateral and medial pterygoids of two sides contract
alternately to produce side-to-side movements

10. Temporal fascia:
Thick aponeurotic sheet- covers temporalis muscle.
Superiorly: single layered - attached to superior
temporal line.
Inferiorly: Two layers- attached to inner and outer
lips of upper border of the zygomatic arch .
Gap contains fat, Middle temporal artery- branch
from superficial temporal artery & zygomatico-
temporal nerve.
• superficial surface receives an expansion from
epicranial aponeurosis.
•Superficial surface gives origin to auricularis
anterior and superior.
•Deep surface gives origin to some fibres of
temporalis muscle.

11. Relations of lateral pterygoid:
key muscle of infratemporal region
Superficial relation :
1. Masseter.
2. Ramus of the mandible.
3. Tendon of temporalis.
4. Superficial head of medial pterygoid.
5. Maxillary artery and its temporal &
masseteric branches.

12. Deep:
1. Mandibular nerve.
2. Middle meningeal artery.
3. Sphenomandibular ligament.
4. Deep head of medial pterygoid muscle.
Pterygoid plexus of veins surrounds the
lateral pterygoid.

13. Structures emerging at upper border:
1. Deep temporal nerves (two in number).
2. Masseteric nerve
Structures emerging at lower border:
1. Inferior alveolar nerve and artery.
2. Lingual nerve.
3. Middle meningeal artery (it passes up deep to the
lower border).
Structures passing through gap between two heads:
1. Maxillary artery- enter to reach pterygopalatine
fossa through pterygomaxillary fissure.
2. Buccal branch of mandibular nerve- leave to
provide sensory innervation to skin & mucus
membrane of the cheek.

14. Relations of Medial pterygoid:
Superficial :
1. Lingual nerve.
2. Inferior alveolar nerve.
3. Inferior alveolar vessels.
4. Lateral pterygoid plate
Deep:
1. Tensor veli palatini & Levator veli palatini
2. Superior constrictor of pharynx.
3. Styloglossus and stylopharyngeus
muscles.

15. MAXILLARY ARTERY:
arises behind neck of mandible.
Supplies: (a) Dura mater (b) External & Middle ears &
auditory tube; (c) upper and lower jaws; (d)Muscles
Of temporal and infratemporal regions; (e) Nose &
paranasal air sinuses; (f) Palate & (g) Root of pharynx
Course and Relations:
•Divided into three parts by lateral pterygoid.
First (mandibular) part: runs horizontally, first between
neck of mandible & sphenoniandibular ligament, and
then along lower border of lateral pterygoid.
second (pterygoid) part: runs upwards & forwards
superficial to lower head of lateral pterygoid
Third (pterygopalatine) part: passes between two
heads of lateral pterygoid & through pterygomaxillary
fissure, to enter pterygopalatine fossa.

17. Branches from the First Part:
1. Deep auricular artery- supplies:
(a) skin of external acoustic meatus, and
(b) outer surfaces of tympanic membrane.
(c) TMJ
2. Anterior tympanic artery- supplies
inner surface of the tympanic membrane & middle
ear
3. Middle meningeal artery-
Supplies meninges as well as the skull bone
-Artery ascends upwards deep to lateral pterygoid
- Enter cranial cavity through foramen spinosum.
-on the greater wing of sphenoid, it divides into frontal
and parietal branches.
-Middle meningeal artery and its branches lie outside
dura and deep to inner surface of skull. Both are
supplied by artery.

18. 4. Accessory middle meningeal artery: supplies
meninges & structures in infratemporal fossa.
5. Inferior alveolar/dental artery- supplies
Molar & premolar teeth and adjoining gum.
Before entering the mandibular foramen, inferior
alveolar artery gives off two branches
(a) Lingual branch: accompanies lingual nerve -
supply mucous membrane of the cheek.
(b) Mylohyoid branch: supplies mylohyoid muscle.
It also gives off mental and incisive branches.
Incisive branch: supplies canine and incisor
Mental branch: supply skin of chin

19. Branches from Second Part
Deep temporal arteries (usually two in number):
supply- temporalis muscle
Pterygoid branches
Supply- medial & lateral pterygoid muscles.
Masseteric artery—supplies the masseter muscle.
Buccal artery —supplies buccinator muscle

20. Branches from Third Part
Posterior superior alveolar artery:
Supply- Molar & premolar teeth & mucus membrane
of maxillary air sinus.
Infraorbital artery: gives the following branches:
In the orbit:
(a) Some branches to orbital contents.
(b) Middle superior alveolar artery to premolar teeth.
(c) Anterior superior alveolar artery - supplies-
maxillary air sinus ,canine & incisor of upper jaw.
In the face:
Branches to supply lacrimal sac, medial angle of eye,
side of nose & upper lip.
Greater palatine artery:
•supplies roof of the mouth & adjoining gum,
•In greater palatine canal artery gives off lesser palatine arteries that emerge through lesser palatine
foramina and supply soft palate & tonsil

21.  Pharyngeal artery:
Supplies- mucus membrane of nasopharynx, auditory
tube, sphenoidal air sinus.
 Artery of pterygoid canal:
supplies - pharynx, auditory tube & tympanic cavity.
Sphenopalatine artery: continuation of maxillary art.
Enters nasal cavity in posterior part of superior meatus
through sphenopalatine foramen.
Here it divides into:
(a) posterior lateral nasal branch
Supply- lateral wall of nose;
Sphenoidal & ethmoidal air sinuses
(b) posterior septal/medial branches
Supply- nasal septum
Sphenopalatine artery- artery of epistaxis

22. Pterygoid Plexus of Veins:
Lies around and within lateral pterygoid muscle
Tributaries of plexus correspond to branches of
maxillary artery
Plexus is drained by maxillary vein(formed at
lower border of lateral pterygoid muscle) which
unites with superficial temporal vein to form
retromandibular vein.
Maxillary vein accompanies only first part of maxillary
artery.
 pterygoid venous plexus communicates with:
(a) Inferior ophthalmic vein via inferior orbital fissure,
(b)cavernous sinus by emissary veins via foramen
Ovale.
(c) Facial vein through deep facial vein

25. PTERYGOPALATINE FOSSA:
Pyramidal Space between body of maxilla & root of
pterygoid process, lateral to perpendicular plate of
palatine bone.
BOUNDARIES:
Anterior: superomedial part of posterior surface of
maxilla .
Posterior: Root of Pterygoid process and adjoining
part of anterior surface of the greater wing of
sphenoid.
Medial: Upper part of perpendicular plate of
palatine. orbital and sphenoidal process of palatine.
Lateral: Fossa opens into infratemporal fossa
through pterygomaxillary fissure.
Superior: Under surface of body of sphenoid
Inferior: Pyramidal process of the palatine bone (in
the angle between maxilla and pterygoid process)

26. COMMUNICATIONS:
Anteriorly:
With orbit through medial end of inferior orbital
fissure.
Posteriorly:
1. With middle cranial fossa via foramen rotundum.
2. With foramen lacerum via pterygoid canal.
3. With pharynx via palatovaginal(pharyngeal)
canal.
Medially:With nose through sphenopalatine
foramen.
Laterally: With infratemporal fossa via
Pterygomaxillary fissure.
Inferiorly: With oral cavity via greater palatine
canals

27. CONTENTS:
1. Maxillary nerve.
2. Pterygopalatine ganglion.
3. Third part of the maxillary artery.

28. THANK YOU