The infraorbital nerve is a terminal branch of which division?

• A. CN V1
• B. CN V2
• C. CN V3
• D. CN VII

Answer: (B)

The infraorbital nerve comes from the maxillary division of the trigeminal nerve, which is the second division of cranial nerve V. After V2 runs from the foramen rotundum into the pterygopalatine fossa, it continues as the infraorbital nerve, passing through the infraorbital canal and exiting the infraorbital foramen to supply sensation to the midface (cheek, upper lip, lower eyelid, and side of the nose). This distinguishes it from other divisions: the ophthalmic division (V1) stays in the orbit and provides sensation to the forehead and eye region, while the mandibular division (V3) supplies the lower face and has motor fibers to muscles of mastication. The facial nerve (CN VII) is a different cranial nerve altogether, mainly controlling muscles of facial expression.