the head

Temporal & Infratemporal FossaByDr. Adel Sahib Al-Mayaly

Lateral view of skull

It is a fan-shape space that covers the lateral surface of the skull.
Boundaries
Content
Temporal fossa

Boundaries:-

Superior Margin: Pair of temporal lines (Superior and inferior temporal lines).
Lateral Margin: Temporal fascia, a fan-shaped Aponeurosis overlying the temporalis muscle
Anterior Margin: Posterior surface of the zygomatic bone.
Inferior Margin: Zygomatic arch laterally; Infratemporal crest of the greater wing of the sphenoid medially


Overview

■Temporalis muscle

■Deep temporal arteries
■Deep temporal nerves
■Superficial temporal artery (from external carotid)
Contents

Temporal Fossa

Contents of temporal fossa

It is the space located deep to the ramus of the mandible.

Boundaries:-
Anteriorly :- the posterior surface of the maxilla.
Posteriorly:-by the styloid apparatus, carotid sheath and deep part of the parotid gland.
Medially:- the lateral pterygoid plate and the superior constrictor muscle of the pharynx.
.


Infratemporal Fossa

Laterally:- the ramus of the mandible.

The roof:- the infratemporal surface of the greater wing of the sphenoid.
The infratemporal fossa has no anatomical floor, being continuous with tissue spaces in the neck
Infratemporal Fossa

• The lateral and medial pterygoid muscles

• The mandibular division of the trigeminal nerve
• The chorda tympani branch of the facial nerve
• The otic parasympathetic ganglion
CONTENTS OF THE INFRATEMPORAL FOSSA






is the lateral pterygoid muscle.
This lies in the roof of the fossa, running anteroposteriorly in a horizontal plane from the region of the pterygoid plates to the
mandibular condyle.

The key to understanding the relationships of structures within the infratemporal fossa.

1-Deep to the muscle arise the branches of the mandibular nerve and the main origin of the medial Pterygoid muscle.
2- The maxillary artery generally passes superficial to the lower head of the lateral pterygoid.
3- The buccal branch of the mandibular nerve passes between the two heads of lateral pterygoid m.
4- Emerging below the inferior border of the muscle are the medial pterygoid muscle and the lingual and inferior alveolar nerves.
5- At the upper border emerge the deep temporal nerves and vessels
6- Concentrated around and within the lateral pterygoid muscle lies a venous network, the pterygoid venous plexus.
Relation of structures

This is the largest division of the trigeminal nerve and is the only one to contain motor as well as sensory fibres.
Developmentally, it is the nerve of the first branchial arch and is thus responsible for supplying structures derived from it.
Its sensory fibres supply the mandibular teeth and their supporting structures, the mucosa of the anterior two-thirds of the tongue

THE MANDIBULAR NERVE

Its motor fibres; supply

1- the four ‘muscles of mastication’
2- the mylohyoid, anterior belly of digastric, tensor veli palatini and tensor tympani muscles.

Course & branches

The mandibular nerve; is formed in the infratemporal fossa by
union of sensory & motor roots.
It leaves the skull at F. ovale
it lies on the tensor veli palatini muscle and is covered laterally by the upper head of the lateral pterygoid muscle (slightly anterior to the neck of the mandible).
After a short course, the nerve divides into a smaller anterior division and a larger posterior division

Course & branches

the main trunk gives off two branches;
1-the meningeal branch and
2- the nerve to medial pterygoid
Then anterior division is mainly motor while the posterior division is mainly sensory.
Course & branches


Branches of anterior division:-
1- Masseteric nerve
2- Deep temporal nerves
3- Nerve to lateral pterygoid
4- Buccal nerve.
Course & branches

Posterior division:-

1- Auriculotemporal nerve
2- Lingual nerve
3- Inferior alveolar nerve
Course & branches

This parasympathetic ganglion lies immediately below the foramen ovale.

It lies on the medial surface of the main trunk of the
mandibular nerve.
It is concerned primarily with supplying the parotid gland.
THE OTIC GANGLION






The preganglionic parasympathetic fibres originate from the inferior salivatory nucleus in the brain stem.
The fibres pass out in the glossopharyngeal nerve (preganglionic).
Postganglionic fibres pass to the gland via the auriculotemporal nerve.
Otic Ganglion

is a terminal branch of the external carotid artery.

It arises within the parotid gland at the level of the neck of the condyle of the mandible.
It enters the infratemporal fossa between the deep surface of the condyle and the sphenomandibular ligament.
At this point, it lies below the auriculotemporal nerve and above the maxillary vein.
It is closely related to the lateral pterygoid muscle.

Maxillary Artery

The course is before, superficial to & after the lateral pterygoid m.
The first part of the maxillary artery has five branches and all enter bone.
1- the deep auricular artery.
2- the anterior tympanic artery
3- The middle meningeal artery
4- Accessory meningeal artery
5- The inferior alveolar artery
Maxillary A.

The second part also has five branches but not enter the bones.

Muscular branches
1- Deep temporal arteries.
2- pterygoid arteries
3- masseteric arteries.
4- A buccal artery
Second Part

in the pterygopalatine fossa,

gives five branches which accompany branches of the maxillary nerve & pterygopalatine ganglion.
1- infraorbital artery:- The artery passes into the orbit via inferior orbital fissure as the small infraorbital artery that passes in the infra orbital canal.
2- Sphenopalatine A.
3- Posterior superior alveolar A.
4- The greater palatine artery
5- The very small pharyngeal artery.


The third part of the maxillary artery

This is situated around, and within, the lateral pterygoid muscle.

and it surrounds the maxillary artery
Its tributaries correspond to the various branches of the maxillary artery
The plexus communicates with the cavernous sinus, the facial vein, the inferior ophthalmic vein and the pharyngeal plexus.
The plexus receives blood from the pterygoid muscles, the deep temporal veins, the middle meningeal veins and from parotid veins).

THE PTERYGOID VENOUS PLEXUS