Heads of lateral pterygoid muscle and infratemporal fossa. The zygomatic arch, coronoid process, condylar process of the mandible, and the temporalis muscle have been removed to expose the infratemporal fossa and lateral pterygoid muscle. The latter consists of two heads: the superior head inserts into the articular capsule and disc of the temporomandibular joint and has been reflected inferiorly. The inferior head attaches to the fovea on the neck of the mandible. The maxillary artery passes deep to the lateral pterygoid muscle in this dissection (usually passes superficial to it) but emerges distally where it is seen giving rise to the anterior deep temporal and posterior superior alveolar arteries before giving rise to the sphenopalatine artery, which enters the pterygopalatine fossa through the pterygomaxillary fissure. The buccinator muscle fills the lower left side of the image. The buccal nerve, a sensory branch of the mandibular nerve, is seen emerging between the two heads of the lateral pterygoid muscle.  A portion of skull bone has been removed to reveal the dura mater covering the brain, which contains the middle meningeal artery. In the retromandibular area one can see a portion of the external and internal carotid arteries, the vagus and hypoglossal nerves, and the vertebral artery. The latter is crossed superficially by the ventral ramus of C2 spinal nerve. Near the origin of the occipital artery from the external carotid, the hypoglossal gives rise from its epineurial sheath to C1 spinal nerve fibers that compose the superior root of the ansa cervicalis that are involved with motor supply to the infrahyoid muscles. (Image courtesy of PA Rubino)