Lab 16 terms (Test 2)

Nerve of the Pterygoid canal

This nerve, carrying sympathetics from the internal carotid plexus via the deep petrosal nerve and parasympathetics via the greater petrosal nerve (CN VII) lies in the floor of the sphenoid sinus. The nerve exits the pterygoid canal and runs into the pterygopalatine ganglion, where the parasympathetics synapse and send branches to the lacrimal, nasal, and palatine glands.

. Nasopalatine Nerve

A branch of maxillary nerve (V2) coursing through the sphenopalatine foramen from the pterygopalatine ganglion. It supplies inervation to the nasal septum and courses through the incisive canal to communicate with the greater palatine nerve.

Posterior Superior Alveolar Nerve

Branches from the maxillary nerve in the pterygopalatine fossa that then pass through the pterygomaxillary fissure to innervate the molar teeth. They pass through small openings in the infratemporal surface of the maxilla.

Pterygomaxillary fissure

Created by the Maxilla and Sphenoid bones, this fissure opens into the pterygopalatine fossa. The pterygopalatine ganglion and maxillary artery both lie in this fissure. The maxillary nerve (terminating as the infraorbital nerve) pass through on the superior side.

Pterygopalatine Fossa

The area found medial to the Pterygomaxillary fissure, and lateral to the sphenopalatine foramen. The pterygopalatine ganglion (Parasympathetics) lies in this fossa.

Posterior Superior Lateral Nasal Nerves

The posterior superior lateral nasal nerve originates off the pterygopalatine ganglion (a branch of V2), and the posterior inferior lateral nasal nerve originates off the greater palatine nerve. Both serve as innervation to the lateral nasal wall, while the anterior ethmoid and nasopalatine nerve innervate the nasal septum.

Maxillary Artery

The third and terminal part of this artery (pterygopalatine part) passes through the pterygomaxillary fissure, before terminating through the sphenopalatine foramen as the sphenopalatine artery.

Posterior Superior Lateral Nasal and Septal Arteries

These are branches from the sphenopalatine artery as it bifurcates after entering the nasal cavity through the sphenopalatine foramen. They supply blood to the lateral and septal walls of the nasal cavity, and form anastomoses with the anterior and posterior ethmoidal arteries.

Middle Superior and Anterior Superior alveolar nerves (V2)

These nerves are branches from the infraorbital nerve and supply sensory innervation to all the teeth except the molar teeth, which are supplied by the posterior superior alveolar nerve.

Greater and Lesser Palatine nerves

These nerves originate from the maxillary branch of trigeminal off of the pterygopalatine ganglion. They descend together in the palatine canal, and then exit the palatine bone through the greater palatine foramen or lesser palatine to innervate the hard and soft palates.

Sphenopalatine foramen

This Foramen is the medial opening of the pterygopalatine fossa. Through here course: Posterior superior lateral nasal arteries and nerves, Posterior superior septal arteries and nerves, the sphenopalatine artery and the nasopalatine nerve (both of which innervate and supply the septum).

Descending Palatine Artery (Branch of Maxillary A.)

This artery branches off of the maxillary artery and descends through the palatine canal with the greater and lesser palatine nerves. It splits into greater and lesser palatine arteries, where they supply the hard and soft palate. The greater palatine artery forms an anastomosis with the sphenopalatine artery.

Sphenopalatine artery

This artery is one of 4 terminal branches of the maxillary artery. It courses through the sphenopalatine foramen, where it bifurcates into posterior superior lateral nasal and septal branches. The lateral nasal branches form anastomoses with the anterior ethmoidal artery and facial artery. The posterior superior lateral nasal branch of sphenopalatine also passes through the incisive foramen and anastomoses with the greater palatine artery. The posterior septal branches form anastomoses with the posterior and anterior ethmoidal arteries.

Zygomatic branch of maxillary nerve

This branch arises just after the maxillary nerve passes through foramen rotundum. It bifurcates into 2 terminal cutaneous branches: zygomaticofacial and zygomaticotemporal. The zygomaticotemporal branch conveys parasympathetics and sympathetics to the lacrimal gland on the lateral wall of the orbit. The zygomatic branches pass through the inferior orbital fissure, then bifurcate. The zygomaticofacial nerve exits through the zygomaticofacial foramen just lateral to the infraorbital foramen. The zygomaticotemporal nerve exits the skull through the zygomaticotemporal foramen.

Palatine Canal

This canal originates on the posterior surface of the palatine bone and allows passage of the greater and lesser palatine nerves, as well as the descending palatine artery.

Maxillary Division of Trigeminal

This division (V2) passes through foramen rotundum into the pterygopalatine fossa. It supplies sensory through various branches to the face, and carries secretomotor fibers from CN VII to the lacrimal, nasal, and palatine glands.

Infraorbital nerve

This is the largest of the terminal branches of the maxillary (V2) nerve. It passes through the inferior orbital fissure (after passing over the pterygopalatine ganglion), courses on the inferior aspect of the orbit. It enters the infraorbital canal and exits the skull through the infraorbital foramen to innervate the skin over the maxilla. NOTE!!!: The infraorbital nerve gives rise to middle superior and anterior superior alveolar nerves.