Lateral perspective of the left mandibular region. The sternocleidomastoid muscle has been retracted posteriorly and reveals the spinal accessory nerve deeply crossing the proximal portion of the internal jugular vein. The masseter muscle covers the ramus and angle of the mandible. The facial vein crosses the submandibular gland around the level of the carotid artery bifurcation and drains into the internal jugular vein. The facial artery courses deep to the posterior digastric and the submandibular gland before emerging to cross the inferior border of the mandible onto the face near the anterior border of the masseter. The artery is tortuous and lies anterior to the facial vein. The superficial temporal artery is located anterior to the external auditory canal and divides over the temporalis fascia into frontal and parietal branches. The posterior belly of the digastric muscle runs anteroinferiorly from the digastric notch of the temporal bone to the hyoid bone, and the anterior belly runs from the hyoid bone to the mandible near the midline. The facial nerve is visible after exiting the stylomastoid foramen and enters the parotid gland (removed). It divides within the gland into its terminal branches, which here in this dissection course anteriorly superficial to the mandible and over the masseter muscle. (Image courtesy of AL Rhoton, Jr.)