Anatomy, Head and Neck: Alveolar Nerve

One of the first features of the human body to be noticed by another person is the face. The face is made up of many different muscles, nerves, bones, and organs and has an intriguing network of motor and sensory innervation. The motor innervation to the muscles located in the face is derived mainly from the facial nerve (CN VII) and trigeminal nerve (CN V). The facial nerve provides innervation to the muscles that are involved in creating facial expressions, whereas the trigeminal nerve innervates the muscles used in mastication. The sensory innervation of the face comes from the trigeminal nerve. The trigeminal nerve subdivides into three main branches that split the face into three territories. The first branch from the trigeminal nerve is the ophthalmic nerve (CN V1). The ophthalmic nerve provides innervation to the forehead, eyes, and nose. The second branch of the trigeminal nerve is the maxillary nerve (CN V2). The maxillary nerve's sensory innervation follows the maxilla bone. The sensory territory of the maxillary nerve will be the cheeks and the upper lip mainly. The last branch from the trigeminal nerve is the mandibular nerve (CN V3). The mandibular nerve is responsible for providing sensory innervation to the regions that correspond to the mandible. These regions are the jawline, chin, and lower lip. The branches of the trigeminal nerve will further divide into smaller nerve branches to optimally provide sensory innervation to their respective territories. For example, the maxillary nerve will branch into the superior alveolar nerves. Another example is the mandibular nerve branching into the inferior alveolar nerve. The inferior alveolar nerve will be responsible for sensory innervation to the cheek, lips, chin, teeth, and gingivae.