Trigeminal (CN V) and Facial (CN VII) Nerves – Lecture Flashcards

A comprehensive set of practical flashcards covering CN V (trigeminal) divisions, their branches, distributions (teeth and oral structures), and CN VII (facial) pathways including parasympathetic components and key ganglia.

CNV1 is which type of nerve and through which cranial opening does it pass?

CNV1 is a sensory (afferent) division of the trigeminal nerve that passes through the Superior Orbital Fissure.

Name the three divisions of the trigeminal nerve and their general roles.

CNV1 Ophthalmic (sensory), CNV2 Maxillary (sensory), CNV3 Mandibular (sensory and motor).

CNV1 branches commonly taught.

Frontal (supraorbital, supratrochlear), Nasociliary (long ciliary, anterior/posterior ethmoidal, infratrochlear), and Lacrimal nerves.

What areas does CNV1 provide general sensory innervation to?

Face, structures of the orbit, nasal cavity, and oral cavity.

CNV2 passes through which foramen/fissure, and what is its key sensory role?

Passes through the Foramen Rotundum; sensory innervation to the maxillary region including the upper dentition.

Major branches of CNV2.

Zygomatic (zygomaticotemporal, zygomaticofacial), Infraorbital, Posterior Superior Alveolar, Middle Superior Alveolar, Anterior Superior Alveolar, Greater Palatine, Lesser Palatine, Nasopalatine, Pharyngeal.

What is the function and origin of the Anterior Superior Alveolar (ASA) nerve?

Sensory to maxillary incisors, canines, and associated gingiva; originates from dental branches of the anterior teeth and exits via apical foramina.

When is the Middle Superior Alveolar (MSA) nerve absent, and what is its function?

Not present in all individuals; supplies premolars and mesiobuccal root of the first molar; if absent, PSA supplies those teeth.

What does the Posterior Superior Alveolar (PSA) nerve innervate and where does it exit?

Sensory to maxillary molars (except MB root) and their gingiva; exits via foramina on the posterior wall of the maxilla and tuberosity.

CNV3 enters the skull through which foramen, and what are its primary roles?

Enters via the Foramen Ovale; mixed sensory to mandible/floor of mouth and motor to muscles of mastication, mylohyoid, anterior belly of digastric, tensor tympani, and tensor veli palatini.

Main divisions and notable branches of CNV3 (anterior vs posterior division).

Anterior division: Deep temporal, masseteric, lateral pterygoid, and long buccal nerves. Posterior division: Auriculotemporal, Lingual, Inferior Alveolar (IA), Mylohyoid, Medial pterygoid, Meningeal, Tensor veli palatini, Tensor tympani.

What is the Long Buccal Nerve and what does it innervate?

Sensory to the skin of the cheek, buccal mucosa, and buccal gingiva of the mandibular posterior teeth; travels between the heads of the lateral pterygoid; distinct from the buccal nerve (CN VII) which innervates buccinator.

Mental nerve and Incisive nerve: origin and What do they innervate?

Incisive nerve from dental branches of anterior and premolar teeth; Mental nerve from the inferior alveolar nerve as it exits the mental foramen; together they contribute sensory innervation to the chin and lower lip (Mental) and anterior teeth (Incisive).

Lingual nerve: distribution and relation to CNV3.

Sensory to the anterior two-thirds of the tongue, floor of the mouth, and lingual gingiva; travels near the distal molars, then between the medial pterygoid and mandible and joins the posterior trunk of CNV3.

CNVII: basic pathway and primary roles.

Facial nerve emerges from the brain, enters the internal acoustic meatus, exits the stylomastoid foramen; motor to facial muscles; carries parasympathetic fibers via Greater Petrosal and Chorda Tympani; sensory to a small ear area.

Greater Petrosal nerve: function and target.

Carries preganglionic parasympathetic fibers to the pterygopalatine ganglion; postganglionic fibers join CNV2 branches to lacrimal gland and nasal/palatal glands; also carries some taste fibers from the palate.

Chorda Tympani: function and pathway.

Carries preganglionic parasympathetic fibers to the submandibular and sublingual glands; travels with the lingual nerve to the floor of the mouth and provides taste for the anterior two-thirds of the tongue.

Pterygopalatine ganglion: role in CNVII parasympathetics.

Ganglion that receives preganglionic parasympathetic fibers from the Greater Petrosal nerve; postganglionic fibers join branches of CNV2 to innervate lacrimal gland and nasal/palatal glands; also related to palatal taste pathways.

Four parasympathetic ganglia of the head.

Ciliary ganglion, Pterygomandibular (pterygopalatine) ganglion, Otic ganglion, Submandibular ganglion.

Parasympathetics of the head: general summary.

In head/neck, parasympathetics innervate lacrimal and salivary glands, mucous glands of oral and nasal cavities, and sphincter pupillae/ciliary muscles; preganglionic fibers arise from CN III, VII, IX and synapse on the listed ganglia; postganglionic fibers hitchhike with CNV branches.

Which openings/foramina correspond to CNV divisions (V1, V2, V3) exiting the skull?

V1 through the Superior Orbital Fissure; V2 through the Foramen Rotundum; V3 through the Foramen Ovale.

Nasopalatine nerve: function and pathway.

Sensory from the palatal mucosa and gingiva of the anterior hard palate; enters incisive canal through incisive foramen, then travels to pterygopalatine fossa with the posterior superior nasal nerve via the sphenopalatine foramen.

Greater and Lesser Palatine nerves: role and course.

Sensory nerves for the palatal mucosa/gingiva; Greater palatine nerve serves posterior hard palate; Lesser palatine nerves serve soft palate; unite with each other to form the palatine nerve and travel through the pterygopalatine canal.