The Maxillary Branch of the Trigeminal Nerve
The trigeminal nerve is the fifth of the twelve cranial nerves, which is divided into three main branches: the ophthalmic nerve, the maxillary nerve, and the mandibular nerve. Its second division is the maxillary branch, which consists of afferent sensory fibers, parasympathetic and sympathetic fibers.
The word afferent means toward the centre, as in from a peripheral area of a limb to the central nervous system . The word efferent is the opposite of afferent, meaning away from the centre and toward the periphery; when the stimulus is carried to the peripheral area from the brain.
The second facial area that is innervated by the maxillary nerve consists of:
- The area under the tip of the nose.
- The nostrils.
- The upper lip.
- The zygomaticofacial area.
- Section of the temporal area.
Branches & Pathway
The pathway for afferent sensory fibers of the maxillary nerve from the proprioceptors until the trigeminal nuclei (after the merger into one main cranial nerve) is the following (from the initiation in the periphery to the termination in the brain):
- The maxillary nerve branches that innervate the maxillary area or the second facial area include the major and minor palatine nerves, the recurrent pharyngeal nerve, the posterior superior nasal nerves, the nasopalatine nerve and the superior alveolar nerve which all synapse on the pterygopalatine ganglion.
- Other maxillary nerve branches that don’t synapse upon the pterygopalatine ganglion but directly continue into the main branch of the maxillary nerve include the infraorbital nerve and the zygomatic nerve branches, namely the recurrent zygomaticofacial nerve and the zygomaticotemporal nerve.
- The main branch of the zygomatic nerve is an exception because it doesn’t directly synapse on the pterygopalatine ganglion, but it does carry both sympathetic and parasympathetic fibers from the ganglion to the lacrimal gland. The middle meningeal nerve is a small branch stemming from the maxillary nerve itself.
- The maxillary nerve synapses on the gasser ganglion (ganglion of the trigeminal nerve) and the postganglionic fibers continue to the pontine nucleus and the spinal nucleus and tract.
Things to remember
- The maxillary nerve (CN V2) is one of three divisions of the trigeminal nerve.
- The maxillary nerve carries the sensory information from the upper lip, palate, nasal cavity, nasopharynx and meninges of the anterior and middle cranial fossae. Also, it carries parasympathetic fibers to and from the pterygopalatine ganglion.
- The maxillary nerve enters the skull through the foramen rotundum before synapsing at the trigeminal ganglion.