TEMPORAL AND INFRATEMPORAL FOSSA

Dr. Motaz NuggedAllaM.Sc (Human Anatomy)

TEMPORAL FOSSA

Temporal Fossa (Boundaries)

The temporal fossa, in which the temporal muscle (L. temporalis) is located, is bounded: Anteriorly by the frontal and zygomatic

bones. Laterally by the zygomatic arch. Inferiorly by the infratemporal crest.

Temporalis Muscle

Origin : Floor of temporal fossa. Insertion : Coronoid procces of

mandible. Innervation : Mandibular division of

trigeminal nerve. Actions : Elevation and retraction of

the mandible.

INFRATEMPORAL FOSSA

The infratemporal fossa is an irregularly shaped space deep and inferior to the zygomatic arch, deep to the ramus of the mandible and posterior to the maxilla.

It communicates with the temporal fossa through the interval between (deep to) the zygomatic arch and (superficial to) the cranial bones.

Boundaries

Laterally: the ramus of the mandible. Medially: the lateral pterygoid plate. Anteriorly: the posterior aspect of the maxilla. Posteriorly: the tympanic plate and the mastoid

and styloid processes of the temporal bone. Superiorly: the inferior (infratemporal) surface

of the greater wing of the sphenoid. Inferiorly: where the medial pterygoid muscle

attaches to the mandible near its angle.

Contents

Inferior part of the temporal muscle. Lateral and medial pterygoid

muscles. Maxillary artery. Pterygoid venous plexus. Mandibular, inferior alveolar, lingual,

buccal, and chorda tympani nerves .

Inferior alveolar nerve

Is a branch from mandibular nerve which enters the mandibular canal to supply the teeth of the lower jaw and emerges through the mental foramen (mental nerve) to supply the skin of the chin.

Inferior Alveolar Nerve Block

The site of the anesthetic injection is around the mandibular foramen.

This canal gives passage to the inferior alveolar nerve, artery, and vein.

When this nerve block is successful, all mandibular teeth are anesthetized to the median plane.

The skin and mucous membrane of the lower lip, the labial alveolar mucosa and gingivae, and the skin of the chin are also anesthetized because they are supplied by the mental nerve, a branch of the inferior alveolar nerve.

The maxillary artery

The maxillary artery is the larger of the two terminal branches of the external carotid artery .

It arises posterior to the neck of the mandible and is divided into three parts based on its relation to the lateral pterygoid muscle .

Each three parts of the maxillary artery give 5 branches .

The Temporomandibular JointTMJ

The TMJ is a modified hinge type of synovial joint .

The articular surfaces involved are the condyle of the mandible, the articular tubercle of the temporal bone, and the mandibular fossa.

The fibrous layer of the capsule attaches to the margins of the articular area on the temporal bone and around the neck of the mandible.

The articular disc divides the TMJ into two separate compartments (two separate synovial cavities and membranes).

Nerve Supply :Auriculotemporal and masseteric branches of the mandibular nerve

THANX