Nervous System: Cranial Nerves and Nerves to Oral Cavity

Flashcards covering key vocabulary related to the nervous system, cranial nerves, and specific nerves to the oral cavity, including their divisions, branches, functions, and associated pathologies, for dental professionals.

Nervous System

An extensive, intricate network of neural structures that activates, coordinates, and controls all functions of the body. has 2 divisions

• central

• peripheral

Innervation

A supply of nerves to a body part, enabling tissues and organs to function.

Neuron

The cellular component of the nervous system.

Afferent Nerve (Sensory Nerve)

A nerve that carries information from the periphery of the body to the brain.

Efferent Nerve (Motor Nerve)

A nerve that carries information away from the brain to the periphery of the body.

Central Nervous System (CNS)

Comprises the brain and spinal cord.

Peripheral Nervous System (PNS)

Comprises sensory and motor nerves outside the central nervous system.

Cranial Nerves

A set of 12 paired nerves that originate directly from the brain and brainstem, passing through the skull, and transmitting sensory and motor information between the brain and various parts of the head, neck, and body.

Olfactory Nerve (CN I)

A sensory cranial nerve responsible for the sense of smell.

Optic Nerve (CN II)

A sensory cranial nerve responsible for vision.

Oculomotor Nerve (CN III)

A motor cranial nerve responsible for eye movement.

Trochlear Nerve (CN IV)

A motor cranial nerve responsible for eye movement.

Trigeminal Nerve (CN V)

A mixed sensory and motor cranial nerve responsible for sensation of the face and teeth, and for mastication.

Abducens Nerve (CN VI)

A motor cranial nerve responsible for eye movement.

Facial Nerve (CN VII)

A mixed sensory (taste anterior 2/3 of tongue) and motor (muscles of facial expression, salivation, lacrimation) cranial nerve.

Vestibulocochlear Nerve (CN VIII)

A sensory cranial nerve responsible for balance and hearing.

Glossopharyngeal Nerve (CN IX)

A mixed sensory (taste and general sensation from base of tongue) and motor (pharyngeal muscles, parotid gland) cranial nerve.

Vagus Nerve (CN X)

A mixed sensory (sensation of the ear) and motor (muscles of soft palate, pharynx, larynx) cranial nerve.

Accessory Nerve (CN XI)

A motor cranial nerve responsible for shrugging shoulders, head turning, and controlling muscles of the soft palate and pharynx.

Hypoglossal Nerve (CN XII)

A motor cranial nerve responsible for the movement of muscles under the tongue.

Trigeminal Nerve Ganglion (Gasserian/Semilunar Ganglion)

A sensory relay station located in the middle cranial fossa at the base of the skull, crucial for transmitting sensory information from the face, head, and oral cavity to the central nervous system.

sensory root of trigeminal nerve divides into 3 parts

• ophthalmic division V1

• maxillary division V2

• mandibular division V3

Ophthalmic Nerve (V1)

The first division of the trigeminal nerve, a sensory nerve that enters the skull via the superior orbital fissure and provides sensation to the upper face and scalp.

Maxillary Nerve (V2)

The second division of the trigeminal nerve, a sensory nerve that enters the skull via the foramen rotundum and provides sensation to the middle face.

Mandibular Nerve (V3)

The third and largest division of the trigeminal nerve, a mixed nerve with both afferent and efferent components, entering the skull via the foramen ovale, and providing sensation to the lower face and innervating muscles of mastication.

the ophthalmic nerve division provides sensation

to the upper face and scalp

the maxillary and mandibular nerve division supplies sensation

to the middle and lower face

ophthalmic nerve in detail

smallest division and serves as afferent nerve for

• conjunctiva

• cornea

• eyeball

• orbit

• forehead

• ethmoidal & frontal sinuses

• part of dura mater

• parts of nasal cavity and nose

Frontal Nerve

A major branch of the ophthalmic nerve (V1) that supplies the scalp, forehead, and upper eyelid.

Lacrimal Nerve

A major branch of the ophthalmic nerve (V1) that supplies the lacrimal gland and upper eyelid.

Nasociliary Nerve

A major branch of the ophthalmic nerve (V1) that supplies the cornea of the eye, nasal cavity, ethmoid sinus, and tip of the nose.

the maxillary nerve serves as an afferent nerve for

• maxillae and overlying skin

• oral mucosa

• maxillary sinuses

• nasal cavity

• palate

• nasopharynx

• part of dura mater

Infraorbital Nerve (IO)

The largest branch of the maxillary nerve (V2), supplying the lower eyelid, nose, and upper lip.

Zygomatic Nerve

A branch of the maxillary nerve (V2) that supplies the skin of the cheek and temporal region.

Anterior Superior Alveolar (ASA) Nerve

An afferent nerve branch of the maxillary nerve (V2) that innervates the maxillary central incisors, lateral incisors, canines, and associated labial periodontium and gingiva to the midline.

Middle Superior Alveolar (MSA) Nerve

An afferent nerve branch of the maxillary nerve (V2) that innervates the maxillary premolar teeth, the mesiobuccal root of the maxillary first molar, and associated buccal periodontium and gingiva, when present.

Posterior Superior Alveolar (PSA) Nerve

An afferent nerve branch of the maxillary nerve (V2) that innervates the mucous membranes of the maxillary sinus, the maxillary molars (except sometimes the mesiobuccal root of the first molar), and associated buccal periodontium and gingiva.

Dental Plexus

A network of nerves found within both the maxillary and mandibular dental arches.

Greater Palatine Nerve (GP or Anterior Palatine Nerve)

An afferent nerve branch of the maxillary nerve (V2) located on the posterior hard palate, supplying sensation to the posterior hard palate and associated palatal periodontium and gingiva of the ipsilateral maxillary posterior teeth.

Lesser Palatine Nerve (LP or Posterior Palatine Nerve)

An afferent nerve branch of the maxillary nerve (V2) that supplies sensation to the soft palate and palatine tonsils.

palatine nerves are joined by

lateral nasal branches

Nasopalatine Nerve (NP Nerve)

An afferent nerve branch of the maxillary nerve (V2) that supplies sensation to the anterior hard palate, associated palatal periodontium and gingiva of the maxillary anterior teeth bilaterally, and the nasal septal tissue, entering the incisive canal via the incisive foramen.

Meningeal Branches (Mandibular Nerve)

Afferent nerves arising from the undivided mandibular nerve (V3) trunk that supply parts of the dura mater.

Medial Pterygoid Nerve

An efferent nerve arising from the undivided mandibular nerve (V3) trunk, innervating the medial pterygoid, tensor veli palatini, and tensor tympani muscles.

Deep Temporal Nerve

An efferent muscular branch of the anterior trunk of the mandibular nerve (V3) that innervates the Temporalis muscle.

Masseteric Nerve

An efferent muscular branch of the anterior trunk of the mandibular nerve (V3) that innervates the Masseter muscle.

Lateral Pterygoid Nerve

An efferent muscular branch of the anterior trunk of the mandibular nerve (V3) that innervates the Lateral Pterygoid muscle.

Buccal Nerve (Long Buccal Nerve)

An afferent nerve branch of the anterior trunk of the mandibular nerve (V3) that supplies sensation to the skin of the cheek, buccal mucosa, and associated buccal periodontium and gingiva of the mandibular molars.

Auriculotemporal Nerve

An afferent nerve branch of the posterior trunk of the mandibular nerve (V3) that supplies sensation to the external ear and scalp.

Lingual Nerve

An afferent nerve branch of the posterior trunk of the mandibular nerve (V3) that provides general sensation for the body of the tongue, the floor of the mouth, and the associated lingual periodontium and gingiva of the mandibular teeth to the midline.

Inferior Alveolar (IA) Nerve

An afferent nerve formed from the merger of the mental and incisive nerves, part of the inferior dental plexus, carrying innervation for the mandibular teeth and associated facial periodontium and gingiva of the mandibular anterior teeth and premolars, as well as labial mucosa.

Inferior Dental Plexus

A network of nerves within the mandibular dental arch, part of the overall dental plexus.

Mental Nerve

An afferent nerve branch of the inferior alveolar nerve that supplies sensation to the chin, lower lip, labial mucosa, and associated facial periodontium and gingiva of the mandibular anterior teeth and premolars to the midline, entering the mental foramen.

Incisive Nerve

An afferent nerve composed of dental and interdental branches from the mandibular anterior teeth and premolars, forming part of the inferior dental plexus.

Mylohyoid Nerve

A small efferent branch of the inferior alveolar nerve that supplies the mylohyoid muscle and the anterior belly of the digastric muscle.

Trigeminal Neuralgia (Tic Douloureux)

A pathology believed to involve pressure on the sensory root of the trigeminal ganglion, causing excruciating short-term pain on one side of the face, typically involving the maxillary or mandibular nerve branches.

Greater Petrosal Nerve

A branch of the facial nerve before it exits the skull, carrying efferent nerve fibers to the pterygopalatine ganglion (for lacrimal, nasal, and minor palatal salivary glands) and afferent fibers for taste sensation in the palate.

Chorda Tympani Nerve

A small branch of the facial nerve that serves as an efferent nerve for the submandibular and sublingual salivary glands and as an afferent nerve for taste sensation for the anterior two-thirds of the body of the tongue; it travels with the lingual nerve.

Submandibular Ganglion

A ganglion communicating with the chorda tympani nerve and lingual nerve, located superior to the deep lobe of the submandibular salivary gland, which it supplies with efferent innervation.

Posterior Auricular Nerve

An efferent branch of the facial nerve after it exits the stylomastoid foramen.

Stylohyoid Nerve

An efferent branch of the facial nerve after it exits the stylomastoid foramen, supplying the stylohyoid muscle.

Posterior Digastric Nerve

An efferent branch of the facial nerve after it exits the stylomastoid foramen, supplying the posterior belly of the digastric muscle.

Temporal Branches (Facial Nerve)

Efferent branches of the facial nerve supplying muscles anterior to the ear, frontal belly of the epicranial muscle, superior orbicularis oculi muscle, and corrugator supercilii muscle.

Zygomatic Branches (Facial Nerve)

Efferent branches of the facial nerve supplying the inferior orbicularis oculi muscle and zygomatic major and minor muscles.

Buccal Branches (Facial Nerve)

Efferent branches of the facial nerve supplying the muscles of the upper lip and nose, buccinator, risorius, and orbicularis oris muscles.

Mandibular Branch (Facial Nerve)

An efferent branch of the facial nerve, distinct from the mandibular nerve (V3), that supplies the muscles of the lower lip and mentalis muscle.

Cervical Branch (Facial Nerve)

An efferent branch of the facial nerve that runs inferior to the mandible to supply the platysma muscle.

Facial Paralysis

The loss of muscular action of the muscles of facial expression, which can be unilateral or bilateral, and transient or permanent.

Bell Palsy

Unilateral facial paralysis with no known cause, characterized by a loss of excitability of the involved facial nerve, with an abrupt onset of symptoms.