Temporal and infratemporal region

TEMPORAL AND INFRATEMPORAL REGIONS

Contents Temporal Fossa Infratemporal Fossa Communications Major Contents Temporal Fascia

1 Contents of Temporal and Infratemporal Regions

Temporal and infratemporal regions include:

  1. Muscles of mastication
  2. Mandibular branch of trigeminal nerve
  3. Temporomandibular joint (TMJ) → allows movements during speech and mastication
  4. Otic ganglion
  5. Maxillary artery

2 Temporal Fossa

  • To understand these regions, the osteology of the temporal fossa and infratemporal fossa should be studied.
  • The temporal fossa lies on the side of the skull.
  • It is bounded by the superior temporal line and the zygomatic arch.

Boundaries

  1. Anterior: Zygomatic and frontal bones
  2. Posterior: Inferior temporal line and supramastoid crest
  3. Superior: Superior temporal line
  4. Inferior: Zygomatic arch (zygoma)
  5. Inferomedial: Communicates with infratemporal fossa
  6. Floor: Parts of:
    • Frontal bone
    • Parietal bone
    • Temporal bone
    • Greater wing of sphenoid
  7. Lateral: Temporal fascia

Contents

  1. Temporalis muscle
  2. Middle temporal artery → branch of superficial temporal artery
  3. Zygomaticotemporal nerve and artery
  4. Deep temporal nerves → supply temporalis muscle
  5. Deep temporal artery → branch of maxillary artery

3 Infratemporal Fossa

It is an irregular space under the base of the skull, below the level of the zygomatic arch.

Boundaries

  1. Anterior: Posterior surface of body of maxilla
  2. Posterior: Styloid process
  3. Roof: Infratemporal surface of greater wing of sphenoid
  4. Medial: Lateral pterygoid plate and pyramidal process of palatine bone, pterygomaxillary fissure with mandibular canal
  5. Lateral: Ramus of mandible

4 Communications of Infratemporal Fossa

The communications of the infratemporal fossa are as follows:

Superiorly

  1. Foramen ovale → communicates with cranial cavity
  2. Foramen spinosum → communicates with cranial cavity
  3. Gap deep to the zygomatic arch → communicates with temporal fossa

Inferiorly

  • Opens and continues with parapharyngeal space

Anteriorly

  • Inferior orbital fissure → communicates with orbit

Medially

  • Pterygomaxillary fissure → communicates with pterygopalatine fossa

5 Major Contents of Infratemporal Fossa

1. Muscles

  • Lateral pterygoid
  • Medial pterygoid
  • Tendon of temporalis

2. Blood Vessels

  • Maxillary artery
  • Maxillary vein
  • Pterygoid venous plexus

3. Nerves

  • Mandibular nerve and its branches
  • Chorda tympani nerve → branch of facial nerve
  • Otic ganglion

4. Ligament

  • Sphenomandibular ligament

6 Temporal Fascia

  • Temporal fascia is a thick aponeurotic sheet.
  • It roofs over the temporal fossa.
  • It covers the temporalis muscle.
  • The fascia is extremely dense.
  • In some species, e.g. tortoise, the temporal fascia is replaced by bone.

Attachments

1. Superiorly

  • The fascia is single layered.
  • It is attached to the superior temporal line.

2. Inferiorly

  • It splits into two layers.
  • These layers are attached to:
    • Inner lip of the upper border of the zygomatic arch
    • Outer lip of the upper border of the zygomatic arch
  • The small gap between the two layers contains:
    • Fat
    • A branch from the superficial temporal artery
    • Zygomaticotemporal nerve

7 Surfaces of Temporal Fascia

1. Superficial Surface

  • Receives an expansion from the epicranial aponeurosis.
  • Gives origin to:
    • Auricularis anterior
    • Auricularis superior
  • It is related to:
    • Superficial temporal vessels
    • Auriculotemporal nerve
    • Temporal branch of facial nerve

2. Deep Surface

  • Gives origin to some fibres of the temporalis muscle.