The Temporal , Parotid , Infratemporal and Submandibular regions

Parotid region

Introduction

Part of the face infront of the ear and below the zygomatic arch . Principal structures in this area are:

  • Massetter
  • Parotid
Masseter Muscle

A muscle of mastication.

Origin: Lower margin of the zygomatic arch

Insertion: Lateral surface of the mandibular ramus.

Blood supply: Branches of facial , maxillary and superficial temporal arteries

Innervation: Masseteric branch of mandibular nerve

Action: Elevates and draws forwards the angle of the mandible when the jaws are approximated.

Parotid gland

 

Position:

  • Side of the face
  • Anterior to the ear
  • Extents from the zygomatic arch to the upper part of the neck
  • Below the external auditory meatus on to the mastoid process
  • Overlies masseter muscle

 
Surfaces & Relations  

 

 

Lateral (superficial) surface:
Postero superior
Medial:
Posteromedial surface:
Anteromedial surface:
 
covered by skin and superficial fascia.
  • External auditory meatus
  • Styloid apparatus
  • Carotid sheath and it contents
  • Facial nerve trunk

  • Mastoid process,
  • Sternocleidomastoid muscle
  • Posterior belly of digastric muscle.
  • Posterior border of mandibular ramus
  • Masseter muscle
  • Medial pterygoid muscle
 
Parotid bed  


The deep lamina of the gland lies on it.

It comprises of:

  • mastoid process and the sternocleidomastoid muscle
  • the ramus of the mandible and the masseter muscle
  • the styloid apparatus
  • the EAM grooves the upper border
Structures traversing the gland  
  1. external carotid artery
  2. facial nerve
  3. retromandibular vein
  4. parotid (pre ocular) lymph nodes

 
The Parotid Duct (of stensen)  

Course

  • Across masseter
  • Pierces buccinator
  • Lies on the middle third of a line between the intertragic notch of the auricle and the midpoint of the philtrum

Termination

  • Mucous membrane opposite the second upper molar tooth.

 
Blood supply  
  • Branches of superficial temporal artery
  • Some twigs from maxillary
  • Veins drain to the retromandibular vein
Lymphatic drainage : nodes
  • Pre auricular
  • Post auricular
  • Sub mandibular
  • Upper deep cervical
Nerve supply  

Parasympathetic

  • Preganglionic fibres arise from cell bodies in the inferior salivary nucleus in the medulla,
  • Fibres travel by way of the glossopharyngeal nerve, its tympanic branch, the tymphanic plexus and the lesser petrosal nerve
  • Synapse in otic ganglion.
  • Post ganglionic fibres travel through auriculo temporal nerve

General sensory

  • Auriculo-temporal nerve
  • Greater Auricular nerve

Symphathetic

  • Superior cervical ganglion by way of the plexus on the external carotid and middle meningeal arteries.