The 5th cranial nerve (CN5) is the largest mixed cranial nerve responsible for sensory input from the face and motor function for mastication. It has several branches including the meningeal, frontal, lacrimal, and nasociliary nerves, which serve various functions and regions. The lacrimal branch receives parasympathetic fibers from the great petrosal nerve of CN VII.

2. • 5th cranial nerve (CN5)
• Largest cranial nerve
• MIXED CRANIAL NERVE
• Sensory to face – 3 dermatomes
• Motor to muscles of mastication

5. Branches
1. Meningeal branch :- to close related structures
2. Frontal nerve :- enters orbit above the common
tendinous ring then divides into supra-orbital and
supratrochlear nerves
3. Lacrimal branch :- receive parasympathetic
fibers from the great petrosal nerve of CN VII
through the zygomatic branch of CN V2
4. Nasociliary nerve :- then divided to
( 6 ) branches