Maxillary Nerve: Structure, Function & Diseases

The maxillary nerve is part of the V. Cranial Nerve. It supplies a large area of the face. In particular, it innervates the area below the eyes to the jaw.

What is the maxillary nerve?

The maxillary nerve is classified under the V cranial nerve. This is the trigeminal nerve. The V. cranial nerve is the largest of the total XII. Cranial nerves. It is part of the central nervous system and its branches cover the supply of the entire face. These are divided into the ophthalmic nerve (V1), the maxillary nerve (V2) and the mandibular nerve (V3). Consequently, the maxillary nerve is the second main branch of the trigeminal nerve. Its fibers are purely sensitive. This means that they are particularly sentient and pick up signals of conscious bodily sensations. The maxillary nerve supplies the facial skin and parts of the mucous membranes. The facial area between the lower eyelid of the eye and the upper lip is part of the supply area of the maxillary nerve. In addition, an area of the paranasal sinuses as well as the upper jaw is innervated by it. Its action extends to the roots of the teeth. Because it acts on the jaw, the maxillary nerve is also called the maxillary nerve. During dental treatments, one of the terminal branches of the maxillary nerve is anesthetized.

Anatomy and structure

The maxillary nerve, as the second main branch of the trigeminal nerve, travels along the basolateral wall of the cavernous sinus after leaving the ganglion. After leaving the ramus meningeus, it passes through the base of the skull in the foramen rotundum. The ramus meningeus supplies the dura mater. The maxillary nerve exits again below the base of the skull and appears below it in the pterygopalatine fossa. At this point, the maxillary nerve divides into three other terminal branches. These are the rami ganglionares, the zygomatic nerve, and the infraorbital nerve. The rami ganglionares emerge from the vegetative ganglion pterygopalatinum and extend to the mucosa of the turbinate. They terminate in the hard as well as soft palate. The zygomatic nerve passes from below into the orbit, on to the lacrimal gland, and then they pierce the zygomatic bone. Thus, its fibers innervate the skin over the zygomatic bone and the anterior temporal region. The fibers of the infraorbital nerve, like the zygomatic nerve, emerge from the inferior orbital fissure. From there, they extend into the skin area of the cheek to the jaw.

Function and tasks

In very general terms, the maxillary nerve supplies large parts of the facial skin of the cheek. The skin is completely innervated by it in the entire area between the eyes and the lip. The ramus meningeus as part of the maxillary nerve supplies the dura mater. It is part of the meninges. This delimits the brain from the skull and envelops it. The rami ganglionares innervate the mucosa of the turbinates, the region of the ethmoid cells and that of the hard as well as soft palate. The palate includes the roof of the oral cavity and the floor of the nasal cavity. The zygomatic nerve is responsible for supplying the lacrimal gland and the anterior skin area of the temples lateral to the eye. This is the area above the temporal bone. The temporal bone is called the os temporale. It includes the middle and inner ear and extends to the temporomandibular joint. In addition, the zygomatic nerve supplies the skin region above the zygomatic bone. The zygomatic bone is called the Os zygomaticum and forms the boundary to the eye socket, the so-called orbit. The infraorbital nerve supplies the skin region of the cheeks between the lower eyelid and the upper lip. This is the area of the maxillary sinus called the maxillary sinus. Other sub-branches of the infraorbital nerve extend to the pain-sensitive teeth of the upper jaw. It supplies all the teeth of the maxilla.

Diseases

Due to its branching nature, complete failure of the maxillary nerve is very rare and considered unlikely. In the case of impairments, it is more likely that individual branches are affected. These then lead to insensitivity of the corresponding skin region. This can happen when local anesthesia is applied to the facial area. In dental treatments, for example, this can occur and lead to a loss of sensory sensitivity in the affected skin area. In oral surgery, various injuries as well as irritation of the nerves in the mouth, jaw and facial area are among the risk factors.The fracture of the zygomatic bone can also cause the nerve fibers in this area to be damaged or impaired. Sensory disturbances up to numbness of the skin region may occur. As a result, the corner of the mouth may droop or the eye may not close properly. Injured nerves in the facial region can regenerate. An injury usually heals without surgical intervention if the nerve was only bruised or stretched. If the nerve fibers have been partially or completely severed, a nerve graft may be obtained through surgery. Although there is no guarantee that the damaged nerve will regenerate completely, a chance of recovery within several months is conceivable. More common than failure of individual branches of the maxillary nerve is hypersensitivity in some regions. As a result, even the smallest touch stimuli can trigger pain or even pain attacks. This is particularly common in the area of the teeth. Tooth inflammation can then lead to pain that is almost unbearable.