Parotid and Infratemporal Regions Flashcards
Parotid Duct
Transversely passes over Masseter then through Buccinator
Opens into Oral Vestibule opposite 2nd maxillary molar tooth
Parotid Gland Innervation
Secretomotor Innervation Parasympathetic innervation from CN IX Sensory Innervation - Great auricular nerve (cervical plexus) - Auriculotemporal nerve (V3)
Parotid Gland Innervation - Parasympathetic
Preganglionic fibers emerge from foramen ovale from lesser petrosal nerve
Synapse at Otic Ganglion
Postganglionic fiber hitch ride from auriculotemporal nerve to arrive at parotid gland
Strucures within the Parotid Gland
Lymph nodes Facial nerve and branches External Carotid Artery Retromandibular Vein Great Auricular Nerve (C2,3)
Temporal Region
Temporal Fossa
Infratemporal Fossa
Temporal Region - Temporal Fossa Boundaries and Muscles
Posteriorly and Superiorly = Temporal lines
Anteriorly = Frontal and zygomatic bones
Laterally = Zygomatic arch
Inferiorly = Infratemporal crest
Muscles = Temporalis and Masseter
Temporal Region - Infratemporal Fossa Boundaries
Laterally = Ramus of mandible Medially = lateral pterygoid plate of sphenoid Anteriorly = posterior part of maxilla Posteriorly = tympanic plate, mastoid and styloid process of temporal bone Superiorly = inferior surface of the greater wing of the sphenoid bone Inferiorly = medial pterygoid's attachment to the angle of the mandible
Temporal Region - Infratemporal Fossa Contents
- Temporalis-Inferior part
- Lateral and Medial pterygoids
- Maxiallary artery and vein
- Pterygoid venous plexus
- Mandibular division of CN V and branches
- Chorda tympani (CN VII)
- Otic ganglion
Muscles of Mastication and Innervation
Innervated by V3
Temporalis
Masseter
Medial and Lateral Pterygoids
Maxillary Artery
Divided into three parts by the lateral pterygoid muscle
Arises posterior to the neck of mandible
Maxillary Artery - Selected Branches
- Inferior Alveolar
- Middle Meningeal
- Deep Temporal (ant and post)
- Infraorbital
- Sphenopalatine
- Descending Palatine
Maxillary Artery - Inferior Alveolar Branch
Enters the mandibular foramen
Supplies inferior teeth
Emerges out the mental foramen as mental artery
Maxillary Artery - Middle Meningial
Enters the foramen spinosum to supply the dura mater
Before it enters the foramen is surrounded by the auriculotemporal nerve
Maxillary Artery - Deep Temporal
Ascends deep to the tempoalis muscle
Maxillary Artery - Infraorbital
Enters inferior orbital fissure to enter the orbit
Runs in floor of orbit to emerge from infraorbital foramen
Maxillary Artery - Sphenopalatine
Enters the superior aspect of the pterygomaxiallary fissure, will enter the nasal cavity via the sphenopalatine foramen
Maxillary Artery - Descending Palatine
Descends in the palate canal within the pterygomaxillary fissure to the hard palate to branch into greater and lesser palatine arteries
Pterygoid Venous Plexus
Anastamoses with the cavernous sinus and maxillary vein
Trigeminal Nerve - Mandiular Division
Motor to 8 muscles MASTMATT (four muscles of mastication and mylohyoid, ant belly of digastric, tensor tympani, tensor veli palatini)
Emerges from cranial vault through foramen ovale
General Sensory Branches
Trigeminal Nerve - Mandibular Division - General Sensory Branches
Meningeal branch to dura mater Buccal nerve (long buccal) Lingual Nerve Inferior Alveolar Auriculotemporal Nerve
Trigeminal Nerve - Mandibular Division - General Sensory Branches - Buccal
General sensory to cheek
Trigeminal Nerve - Mandibular Division - General Sensory Branches - Lingual
General sensory to anterior 2/3 of tongue
Carried in nerve is Chorda Tympani
Trigeminal Nerve - Mandibular Division - General Sensory Branches - Inferior Alveolar
Enters the mandibular foramen
Gives off nerve to the mylohyoid, motor to mylohyoid and ant belly of digastric
Supplies mandibular teeth and emerges through mental foramen as the mental nerve
Trigeminal Nerve - Mandibular Division - General Sensory Branches - Auriculotemporal
Sensory to auricle, external auditory meatus, tympanic membrane, parotid gland, TMJ, scalp-anterior to the ear
Carries postganglionic parasympathetic fibers from otic ganglion to parotid ganglion
Chorda Tympani
- Leaves facial nerve posterior to middle ear cavity
- Runs deep to tympanic membrane over malleus
- Emerges from skull into infratemporal fossa and joins the lingual nerve
- Conveys taste from anterior 2/3 of tongue
- Conveys preganglionic parasymp to the submandibular and sublingual glands
Otic Ganglion
Postganglionic parasympathetic neurons to parotid gland
Just inferior to foramen ovale
Temporomandibule Joint
- Modified hinge joint
TMJ - Articular Surfaces
Head of Mandible
Articular tubercle and mandibular fossa
TMJ - Articular Disc
Divides joint into an upper cavity (gliding movements; protrusion and retrusion) and a lower cavity (hinge movements; opening and closing)
TMJ - Nerve Suply
Auriculotemporal Nerve
Masseteric Nerve
TMJ - Movements - Elevation
Close Mouth
Temporal
Masseter
Medial Pterygoid
TMJ - Movements - Depression
Open Mouth Lateral Pterygoid Suprahyoid Infrahyoid Gravity is main player though
TMJ - Movements - Protrusion
Lateral Pterygoig
Masseter with assistance from medial pterygoid
TMJ - Movements - Retrusion
Temporalis
Massester
TMJ - Movements - Lateral Movements
Glide and Chew
Temporalis of same side
Pterygoids of opposite side
Masseter
