Infraorbital nerve

Infraorbital nerve is the distal continuation of the maxillary (V2) division of trigeminal nerve. The maxillary nerve–which is running inside the pterygopalatine fossa–passes through the inferior orbital fissure to enter the orbital cavity. Here it travels through the infraorbital groove and canal in the floor of the orbital cavity as the infraorbital nerve. The nerve then exits through the infraorbital foramen to emerge out onto the face.

The infraorbital nerve gives off several branches, some within the infraorbital groove and canal, while others are given off after it has emerged out of the infraorbital foramen.

The branches given off within the infraorbital groove and canal include the middle and anterior superior alveolar nerves. These run in the lateral and anterior walls of maxillary sinus, respectively. They end up supplying the premolar, canine and incisor teeth and also contribute to the superior dental plexus.

Once the infraorbital nerve exits the infraorbital foramen, it gives off terminal branches, including the inferior palpebral, (internal and external) nasal and superior labial branches. The inferior palpebral innervate skin and conjunctiva of lower eyelid. The superior labial branches innervate skin over the cheek and upper lip and related oral mucosa (in the buccal vestibule). The nasal branches are external and internal. The external nasal branches supply the area between the root and the ala of the nose, whereas, the internal nasal branches extend medially by passing superficial to the depressor septi muscle along the ala and ends up providing sensory innervation to the philtrum, nasal septum and vestibule of nose.