Which cranial nerve innervates the muscles of mastication?

The cranial nerve responsible for innervating the muscles of mastication is the mandibular branch of the trigeminal nerve, known as CN V3. This nerve is the largest of the three branches of the trigeminal nerve (trigeminal nerve being CN V) and is primarily responsible for sensory innervation to the lower face, as well as the motor innervation of the muscles involved in chewing.

The muscles of mastication include the masseter, temporalis, and pterygoid muscles, which work together to enable the complex movements of the jaw necessary for breaking down food. The mandibular branch transmits motor signals from the central nervous system to these muscles, facilitating their contraction and thus allowing for effective mastication.

In contrast, the facial nerve (CN VII) primarily controls the muscles of facial expression and does not innervate the muscles responsible for chewing. The glossopharyngeal nerve (CN IX) is mainly involved in functions related to the throat, such as swallowing and salivation, while the hypoglossal nerve (CN XII) primarily controls the muscles of the tongue, playing no direct role in mastication. Therefore, the involvement of the mandibular branch of the trigeminal nerve in providing