Which cranial nerve innervates the temporomandibular joint (TMJ)?

• A. Facial nerve
• B. Glossopharyngeal nerve
• C. Trigeminal nerve
• D. Vagus nerve

Answer: (C)

The correct choice, the trigeminal nerve, is crucial in the mechanics of the temporomandibular joint (TMJ) due to its sensory and motor functions. The trigeminal nerve, primarily through its mandibular branch (V3), innervates the muscles responsible for mastication, such as the masseter, temporalis, and pterygoid muscles. This innervation allows for the movement of the jaw, which is essential for various functions like chewing and speaking.

In addition to its motor functions, the trigeminal nerve also provides sensory innervation to the area around the TMJ, which includes sensation to the skin of the face and the mucosa of the mouth. This dual role makes the trigeminal nerve integral to the proper functioning of the joint, as it facilitates both movement and sensory feedback.

The other options do not provide the appropriate innervation for the TMJ. The facial nerve primarily innervates muscles of facial expression and does not have a role in jaw movement. The glossopharyngeal nerve is involved in taste and some aspects of swallowing, without direct influence on the TMJ. The vagus nerve is involved in autonomic functions and does not innervate the areas related to the