Corpus: Mental nerve

The mental nerve is a sensory terminal branch of the inferior alveolar nerve from the mandibular nerve (V3). It supplies the skin of the chin and the lower lip.

The mental nerve branches off from the inferior alveolar nerve and exits the alveolar canal of the mandible through the mental foramen. Beneath the depressor anguli oris muscle, it splits into three small sensory branches. One branch runs to the chin, while the other two supply the skin and mucosa of the lower lip and the gingiva below the mandibular anterior teeth. These branches communicate partially with the terminal branches of the facial nerve and with nerve branches on the opposite side.

The mental nerve is assessed during the examination of the three exit points of the terminal branches of the trigeminal nerve on the face. If the trigeminal pressure points are painful on palpation, this may indicate pathological changes along the course of the trigeminal nerve.

Damage to the inferior alveolar nerve can lead to sensory disturbances in the area supplied by the mental nerve, such as hypoesthesia, paresthesia, or anesthesia. This symptom is also known as Vincent's symptom or numb chin syndrome (NCS).

The mental nerve can be anesthetized by injecting a local anesthetic near the mental foramen, for example, to treat lacerations of the lower lip. Anesthesia also allows for procedures on the incisive nerve, facilitating dental treatments on the anterior premolars, canines, and anterior teeth of the lower jaw. However, residual sensitivity from the contralateral nerve must be expected.