The third aortic arch constitutes the commencement of the internal carotid artery, and is therefore named the carotid arch. Note that the external carotid buds from the horns of the aortic sac left behind by the regression of the first two arches. The common stem of the infraorbital and mandibular branches passes between the two roots of the auriculotemporal nerve and becomes the middle meningeal artery the original supraorbital branch of the stapedial is represented by the orbital twigs of the middle meningeal. On the obliteration of the stapedial artery, this anastomosis enlarges and forms the internal maxillary artery branches formerly of the stapedial artery are subsequently considered branches of the internal maxillary artery. The infraorbital and mandibular branches arise from a common stem, the terminal part of which anastomoses with the external carotid artery. A remnant of the second arch also forms the hyoid artery. The stapedial artery passes through the ring of the stapes and divides into supraorbital, infraorbital, and mandibula branches which follow the three divisions of the trigeminal nerve. The ventral end of the second develops into the ascending pharyngeal artery, and its dorsal end gives origin to the stapedial artery, a vessel which typically atrophies in humans but persists in some mammals.
A remnant of the 1st arch forms part of the maxillary artery, a branch of the external carotid artery. The first and second arches disappear early. The aortic arches are formed sequentially within the pharyngeal arches and initially appear symmetrical on both sides of the embryo, but then undergo a significant remodelling to form the final asymmetrical structure of the great arteries. They are ventral to the dorsal aorta and arise from the aortic sac.
#Aortic arch series#
The aortic arches or pharyngeal arch arteries (previously referred to as branchial arches in human embryos) are a series of six paired embryological vascular structures which give rise to the great arteries of the neck and head.
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