Maxillary Nerve (V2)

The maxillary nerve, or maxillary division of the trigeminal nerve (V2), is the second of the three major divisions of cranial nerve V. It is a purely sensory nerve that carries general somatic sensation from a broad region of the central face and from numerous deeper structures associated with the nasal cavity, palate, maxillary teeth, paranasal sinuses, and cranial dura.

V2 arises from the trigeminal ganglion within the middle cranial fossa. It travels anteriorly in the lateral wall of the cavernous sinus and leaves the cranial cavity through the foramen rotundum. It then enters the pterygopalatine fossa, where it gives rise to several important branches and communicates with the pterygopalatine ganglion.

The nerve continues anteriorly through the inferior orbital fissure as the infraorbital nerve. After passing through the infraorbital groove and canal, it emerges onto the face through the infraorbital foramen and divides into terminal branches supplying the lower eyelid, lateral nose, cheek, and upper lip.

Classification

The maxillary nerve is a general somatic afferent division of the trigeminal nerve.

Unlike the mandibular division, V2 contains no intrinsic branchial motor component.

Some branches of V2 carry autonomic fibers that originate from other nerves and ganglia, but these fibers are distributed along V2 rather than originating from the maxillary nerve itself.

Trigeminal Nerve Relationship

The trigeminal nerve (CN V) is the principal somatic sensory nerve of the face.

Its three major divisions are:

• Ophthalmic nerve (V1)
• Maxillary nerve (V2)
• Mandibular nerve (V3)

V1 and V2 are purely sensory, while V3 contains both sensory and motor fibers.

Trigeminal Ganglion

The sensory fibers of V2 arise from neurons whose cell bodies are located predominantly within the trigeminal ganglion, also called the semilunar or Gasserian ganglion.

The ganglion lies within Meckel's cave, a dural recess near the apex of the petrous temporal bone.

The maxillary division arises from the central portion of the anterior aspect of the ganglion, between V1 and V3.

Intracranial Course

After leaving the trigeminal ganglion, V2 travels anteriorly within the middle cranial fossa.

It enters the lateral wall of the cavernous sinus and continues toward the foramen rotundum.

During this intracranial portion of its course, V2 gives rise to a meningeal branch supplying cranial dura.

Cavernous Sinus

The maxillary nerve travels within the lateral wall of the cavernous sinus.

Within this wall, it lies inferior to the ophthalmic division of the trigeminal nerve.

Lesions involving the cavernous sinus can therefore affect V2 together with other cranial nerves passing through or along the sinus.

Foramen Rotundum

The foramen rotundum is an opening in the greater wing of the sphenoid bone.

It transmits the maxillary nerve from the middle cranial fossa into the pterygopalatine fossa.

The association between V2 and the foramen rotundum is an important anatomical landmark for skull-base imaging and clinical localization.

Pterygopalatine Fossa

The pterygopalatine fossa is a small, deeply located space between the posterior surface of the maxilla and the pterygoid process of the sphenoid.

V2 enters the fossa through the foramen rotundum.

Within the fossa, it gives rise to the zygomatic nerve, ganglionic branches to the pterygopalatine ganglion, and the infraorbital nerve as its continuation.

Major Branches

Important branches and continuations of V2 include:

• Meningeal branch
• Ganglionic branches
• Zygomatic nerve
• Posterior superior alveolar nerve
• Infraorbital nerve
• Middle superior alveolar nerve, when present
• Anterior superior alveolar nerve

Additional sensory branches reach the nasal cavity, palate, nasopharynx, and related regions through the pterygopalatine ganglion.

Meningeal Branch

The meningeal branch of V2 arises within the middle cranial fossa.

It provides sensory innervation to portions of the dura mater.

These fibers contribute to the trigeminal sensory innervation of intracranial meningeal structures.

Ganglionic Branches

Short ganglionic branches connect V2 with the pterygopalatine ganglion.

General sensory fibers from V2 pass through the ganglion without synapsing.

The ganglion also distributes parasympathetic and sympathetic fibers that subsequently travel with branches associated with V2.

Pterygopalatine Ganglion

The pterygopalatine ganglion is a parasympathetic ganglion located within the pterygopalatine fossa and suspended from V2 by ganglionic branches.

Preganglionic parasympathetic fibers originate functionally from the facial nerve and reach the ganglion through the greater petrosal nerve and nerve of the pterygoid canal.

After synapsing, postganglionic parasympathetic fibers are distributed through branches associated with V2 to glands of the nasal cavity, palate, nasopharynx, and lacrimal pathway.

Nerve of the Pterygoid Canal

The nerve of the pterygoid canal carries preganglionic parasympathetic and postganglionic sympathetic fibers toward the pterygopalatine ganglion.

Its parasympathetic fibers arise from the greater petrosal nerve, while sympathetic fibers arrive through the deep petrosal nerve.

Only the parasympathetic fibers synapse within the pterygopalatine ganglion.

Zygomatic Nerve

The zygomatic nerve arises from V2 in the pterygopalatine fossa.

It enters the orbit through the inferior orbital fissure and divides into the zygomaticofacial and zygomaticotemporal nerves.

These branches provide sensory innervation to skin over the prominence of the cheek and temporal region.

Zygomaticofacial Nerve

The zygomaticofacial nerve passes through a foramen in the zygomatic bone to reach the face.

It supplies sensation to a small region of skin over the prominence of the cheek.

Its cutaneous territory forms part of the broader V2 sensory distribution.

Zygomaticotemporal Nerve

The zygomaticotemporal nerve travels through the zygomatic bone and supplies a region of the anterior temporal skin.

It also communicates with the lacrimal nerve, a branch of V1.

This communication provides an important route for secretomotor fibers destined for the lacrimal gland.

Lacrimal Secretomotor Pathway

Postganglionic parasympathetic fibers from the pterygopalatine ganglion can travel with the zygomatic nerve and its zygomaticotemporal branch.

They then pass through a communicating branch to the lacrimal nerve of V1.

The lacrimal nerve carries these fibers to the lacrimal gland, where they promote secretion.

Posterior Superior Alveolar Nerve

The posterior superior alveolar nerve commonly arises from V2 within the pterygopalatine fossa.

Its branches descend along the posterior surface of the maxilla and enter alveolar foramina.

They supply most maxillary molar teeth, adjacent buccal gingiva, and portions of the maxillary sinus.

Infraorbital Nerve

The infraorbital nerve is the direct continuation of V2 after the maxillary nerve gives off branches within the pterygopalatine fossa.

It enters the orbit through the inferior orbital fissure.

The nerve then travels anteriorly along the floor of the orbit within the infraorbital groove and infraorbital canal.

Inferior Orbital Fissure

The inferior orbital fissure connects the orbit with the pterygopalatine and infratemporal fossae.

The infraorbital nerve and zygomatic nerve enter the orbit through this fissure.

This opening is therefore an important transition point in the extracranial course of V2.

Infraorbital Groove and Canal

After entering the orbit, the infraorbital nerve travels along the orbital floor in the infraorbital groove.

It then enters the infraorbital canal within the maxilla.

During this course, superior alveolar branches arise and descend toward the maxillary teeth and maxillary sinus.

Middle Superior Alveolar Nerve

The middle superior alveolar nerve is variable and may be absent.

When present, it usually arises from the infraorbital nerve within the infraorbital groove or canal.

It commonly supplies the maxillary premolars and contributes to innervation of the maxillary sinus and adjacent gingival structures.

Anterior Superior Alveolar Nerve

The anterior superior alveolar nerve arises from the infraorbital nerve within the infraorbital canal.

It descends within the anterior wall of the maxilla.

It supplies the maxillary incisors and canine teeth and contributes sensory fibers to the maxillary sinus and anterior nasal region.

Superior Dental Plexus

The superior alveolar nerves communicate within the maxilla to form the superior dental plexus.

This network distributes sensory fibers to the maxillary teeth and their supporting structures.

The exact contribution of individual superior alveolar branches varies between individuals.

Maxillary Teeth

Dental Region	Typical Sensory Supply
Maxillary molars	Posterior superior alveolar nerve
Maxillary premolars	Middle superior alveolar nerve when present
Maxillary canine	Anterior superior alveolar nerve
Maxillary incisors	Anterior superior alveolar nerve

Because the middle superior alveolar nerve is frequently absent, neighboring alveolar branches may supply its usual territory.

Maxillary Sinus

Sensory innervation of the maxillary sinus is derived largely from superior alveolar branches of V2.

The close anatomical relationship between the maxillary sinus and upper teeth contributes to overlapping pain patterns.

Inflammation within the sinus can sometimes be perceived as dental pain, while dental disease can produce symptoms involving the sinus region.

Infraorbital Foramen

The infraorbital nerve leaves the infraorbital canal and emerges onto the face through the infraorbital foramen.

The foramen is located on the anterior surface of the maxilla inferior to the orbital margin.

It is an important surface landmark for examination and regional anesthesia.

Terminal Infraorbital Branches

After emerging through the infraorbital foramen, the nerve divides into terminal cutaneous branches.

These include:

• Inferior palpebral branches
• External nasal branches
• Superior labial branches

Together they supply much of the central V2 territory of the face.

Inferior Palpebral Branches

The inferior palpebral branches ascend toward the lower eyelid.

They provide sensory innervation to the skin and conjunctival region of the lower eyelid.

They communicate with neighboring facial sensory branches in this region.

External Nasal Branches

The external nasal branches travel medially toward the lateral surface of the nose.

They provide cutaneous sensation to portions of the side of the nose.

This territory lies between sensory regions supplied by neighboring trigeminal branches.

Superior Labial Branches

The superior labial branches descend toward the upper lip.

They supply sensation to the skin and mucosa of the upper lip and adjacent facial region.

These branches form an important part of the terminal cutaneous distribution of V2.

Pterygopalatine Branches

Sensory fibers from V2 pass through the pterygopalatine ganglion into branches supplying the nasal cavity, palate, and nasopharyngeal region.

These branches include the greater and lesser palatine nerves, nasopalatine nerve, posterior superior lateral nasal branches, and pharyngeal branch.

Although anatomically associated with the ganglion, their general sensory fibers originate from V2 and pass through the ganglion without synapsing.

Greater Palatine Nerve

The greater palatine nerve descends through the greater palatine canal and emerges through the greater palatine foramen.

It travels anteriorly along the hard palate.

It supplies general sensation to much of the hard palate and palatal gingiva and also carries autonomic fibers to palatal glands.

Lesser Palatine Nerves

The lesser palatine nerves descend through the palatine canal and emerge through the lesser palatine foramina.

They primarily supply sensation to the soft palate and tonsillar region.

They also distribute autonomic fibers to glands within the palatal mucosa.

Nasopalatine Nerve

The nasopalatine nerve enters the nasal cavity through the sphenopalatine foramen.

It travels across the roof of the nasal cavity and descends along the nasal septum toward the incisive canal.

It supplies sensation to the nasal septum and anterior portion of the hard palate.

Posterior Superior Lateral Nasal Branches

The posterior superior lateral nasal branches enter the nasal cavity through the sphenopalatine foramen.

They supply sensory fibers to portions of the lateral nasal wall.

They also carry autonomic fibers associated with mucosal glands.

Pharyngeal Branch

A small pharyngeal branch passes posteriorly from the pterygopalatine region through the palatovaginal canal.

It supplies mucosa of the nasopharyngeal region.

Like other branches associated with the pterygopalatine ganglion, it can carry sensory and autonomic fibers.

Sensory Distribution of V2

The maxillary nerve provides sensation to a broad region extending from the lower eyelid to the upper lip.

Important sensory territories include:

• Lower eyelid
• Cheek
• Lateral nose
• Upper lip
• Maxillary teeth and gingiva
• Maxillary sinus
• Nasal cavity
• Hard and soft palate
• Portions of the nasopharynx
• Parts of the cranial dura

Cutaneous Distribution

The cutaneous distribution of V2 occupies the middle region of the face.

It lies between the ophthalmic territory superiorly and mandibular territory inferiorly.

Clinically, sensation is often tested over the cheek when evaluating the maxillary division.

Nasal Cavity Innervation

V2 provides substantial sensory innervation to the nasal cavity through branches associated with the pterygopalatine ganglion.

These fibers supply portions of both the nasal septum and lateral nasal wall.

They carry general sensory information such as touch, pain, and temperature.

Palatal Innervation

The palate receives extensive sensory innervation from branches of V2.

The greater palatine nerve supplies much of the hard palate, the lesser palatine nerves supply much of the soft palate, and the nasopalatine nerve supplies the anterior hard palate near the incisive region.

These nerves are important targets for dental and oral surgical anesthesia.

Autonomic Fibers Distributed with V2

V2 provides important anatomical routes for autonomic fibers despite being fundamentally a somatic sensory nerve.

Postganglionic parasympathetic fibers from the pterygopalatine ganglion travel with branches of V2 toward glands of the nose and palate and indirectly toward the lacrimal gland.

Postganglionic sympathetic fibers also travel with these branches to vascular and glandular targets.

V2 and the Lacrimal Gland

The maxillary nerve participates indirectly in the secretomotor pathway to the lacrimal gland.

Postganglionic parasympathetic fibers leave the pterygopalatine ganglion and travel with the zygomatic nerve of V2.

They pass through a communicating branch to the lacrimal nerve of V1 and ultimately reach the lacrimal gland.

Course Summary

The principal course of V2 can be summarized as:

1. Arises from the trigeminal ganglion
2. Travels in the lateral wall of the cavernous sinus
3. Leaves the middle cranial fossa through the foramen rotundum
4. Enters the pterygopalatine fossa
5. Gives branches to the pterygopalatine ganglion, zygomatic region, and posterior maxillary structures
6. Continues as the infraorbital nerve
7. Enters the orbit through the inferior orbital fissure
8. Travels through the infraorbital groove and canal
9. Gives superior alveolar branches to the maxillary teeth
10. Emerges through the infraorbital foramen
11. Divides into terminal facial branches

Clinical Significance

Maxillary Nerve Lesion

A lesion involving V2 can cause sensory loss or altered sensation within the middle region of the face.

Depending on the level of injury, deficits can involve the cheek, lower eyelid, upper lip, maxillary teeth, palate, nasal cavity, or other V2 territories.

Because V2 is sensory, an isolated lesion does not directly produce weakness of the muscles of mastication.

Trigeminal Neuralgia

Trigeminal neuralgia can involve the maxillary division and produce recurrent episodes of severe facial pain.

Pain in a V2 distribution may involve the cheek, upper lip, lateral nose, or maxillary dental region.

Episodes can be triggered by relatively mild sensory stimulation within the affected territory.

Infraorbital Nerve Injury

The infraorbital nerve can be injured by midfacial trauma, orbital floor fractures, maxillary fractures, or surgical procedures.

Injury can produce numbness or paresthesia of the lower eyelid, cheek, lateral nose, and upper lip.

The pattern of sensory loss helps localize the lesion to the distal V2 pathway.

Orbital Floor Fracture

The infraorbital nerve travels along the floor of the orbit and is vulnerable in orbital floor fractures.

Patients may develop reduced sensation over the cheek and upper lip.

This sensory finding can accompany ocular movement abnormalities caused by other structures affected by the fracture.

Infraorbital Nerve Block

An infraorbital nerve block can anesthetize portions of the midface supplied by terminal infraorbital branches.

The nerve can be approached near the infraorbital foramen.

Depending on anesthetic placement and anatomical variation, the block can also affect anterior superior alveolar branches.

Posterior Superior Alveolar Nerve Block

A posterior superior alveolar nerve block is used to anesthetize sensory innervation associated with maxillary molar teeth.

The nerve is approached near the posterior surface of the maxilla.

Knowledge of the nearby maxillary artery and pterygoid venous plexus is important because of the possibility of vascular puncture and hematoma.

Greater Palatine Nerve Block

The greater palatine nerve can be anesthetized near the greater palatine foramen.

This produces anesthesia of a substantial portion of the posterior hard palate on the treated side.

The technique is commonly relevant to dental and oral surgical procedures involving palatal tissues.

Nasopalatine Nerve Block

The nasopalatine nerve can be anesthetized near the incisive region.

This provides anesthesia to the anterior hard palate.

The nerve's course through the incisive canal is an important landmark in anterior maxillary procedures.

Maxillary Sinus Pain

Inflammation of the maxillary sinus can stimulate sensory fibers derived from V2.

Because superior alveolar nerves also supply maxillary teeth, pain from the sinus can sometimes resemble dental pain.

The anatomical relationship between the sinus floor and roots of upper teeth contributes to this overlap.

Dental Pain

Pain arising from maxillary teeth is transmitted through superior alveolar branches of V2.

The convergence and overlap within the superior dental plexus can make precise localization of dental pain difficult in some circumstances.

Dental and sinus sources of pain may also overlap because they share branches of the same trigeminal division.

Pterygopalatine Fossa Lesions

Lesions within the pterygopalatine fossa can affect several branches of V2 simultaneously.

Depending on the structures involved, sensory abnormalities can affect the palate, nose, maxillary teeth, cheek, and other regions.

The fossa also provides pathways through which disease can spread between the orbit, nasal cavity, oral cavity, infratemporal fossa, and middle cranial fossa.

Foramen Rotundum Lesions

A lesion involving V2 at the foramen rotundum can affect the nerve before its major extracranial branches separate.

This may produce widespread sensory abnormalities throughout the maxillary distribution.

Recognition of this pattern can help localize disease to the skull base.

Cavernous Sinus Lesions

V2 travels in the lateral wall of the cavernous sinus and may be affected by lesions in this region.

Because several cranial nerves are closely associated with the cavernous sinus, V2 sensory loss may occur together with ocular motor abnormalities or sensory changes in the V1 territory.

The combination of deficits can help identify the anatomical level of a lesion.

Perineural Tumor Spread

V2 and its branches can provide pathways for perineural spread of tumors from facial, nasal, palatal, or other head and neck regions.

Disease can extend along the nerve toward the pterygopalatine fossa, foramen rotundum, and intracranial trigeminal pathways.

Knowledge of the complete anatomical course of V2 is therefore important when evaluating skull-base and head and neck imaging.

Clinical Examination

The sensory function of V2 can be examined by testing corresponding areas of the middle face on both sides.

Light touch is commonly assessed over the cheek, with additional sensory modalities tested when clinically appropriate.

V1 and V3 territories should also be examined to determine whether sensory dysfunction is limited to V2 or involves a larger portion of the trigeminal system.

Testing V2 Sensation

The examiner compares sensation over the right and left cheeks or other representative regions within the maxillary distribution.

Reduced or abnormal sensation can result from lesions affecting a peripheral branch, the main V2 trunk, trigeminal ganglion, trigeminal root, or central sensory pathways.

The geographical extent of sensory loss is therefore important for anatomical localization.

V1, V2 and V3 Comparison

Division	Type	Skull Opening	Major Distribution
V1, Ophthalmic	Sensory	Superior orbital fissure	Upper face, forehead, cornea and dorsum of nose
V2, Maxillary	Sensory	Foramen rotundum	Midface, maxillary teeth, nasal cavity and palate
V3, Mandibular	Sensory and motor	Foramen ovale	Lower face, mandibular teeth, anterior tongue general sensation and muscles of mastication

Major V2 Branches and Distribution

Branch	Major Distribution
Meningeal branch	Cranial dura
Zygomatic nerve	Cheek and temporal skin, autonomic route toward lacrimal gland
Posterior superior alveolar nerve	Maxillary molars, gingiva and maxillary sinus
Middle superior alveolar nerve	Usually premolars and related structures when present
Anterior superior alveolar nerve	Canine, incisors, maxillary sinus and nasal region
Infraorbital nerve	Lower eyelid, lateral nose, cheek and upper lip
Greater palatine nerve	Hard palate and palatal gingiva
Lesser palatine nerves	Soft palate
Nasopalatine nerve	Nasal septum and anterior hard palate

Key Anatomical Features

Feature	Key Point
Nerve	Maxillary division of trigeminal nerve, V2
Type	Purely sensory
Sensory ganglion	Trigeminal ganglion
Cavernous sinus	Travels in lateral wall
Skull exit	Foramen rotundum
Major extracranial space	Pterygopalatine fossa
Major continuation	Infraorbital nerve
Orbital entry	Inferior orbital fissure
Facial exit	Infraorbital foramen
Major facial territory	Lower eyelid, cheek, lateral nose and upper lip
Dental territory	Maxillary teeth
Palatal territory	Hard and soft palate through associated branches
Nasal territory	Portions of nasal septum and lateral nasal wall
Associated autonomic ganglion	Pterygopalatine ganglion

Anatomical Importance

The maxillary nerve forms the major sensory pathway for the middle region of the face and many deeper structures of the midface. Its course from the trigeminal ganglion through the cavernous sinus, foramen rotundum, pterygopalatine fossa, orbit, and infraorbital canal provides a continuous anatomical pathway from the cranial cavity to the face.

Its branches supply the maxillary teeth, maxillary sinus, nasal cavity, palate, cheek, upper lip, lower eyelid, and lateral nose. The close relationship of these branches explains several clinically important patterns of referred pain and provides anatomical targets for regional anesthesia.

V2 also acts as an important distribution network for autonomic fibers associated with the pterygopalatine ganglion. Through these relationships, the maxillary nerve contributes to facial sensation, dental sensation, nasal and palatal sensation, sinus sensation, meningeal sensation, and the distribution of secretomotor fibers to glands of the midface.