32 Arteries of Heaa and Neck 







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The internal maxillary, the larger terminal division of the 

 ternal carotid, hurries inwards and forwards from the parotid gland, 

 passing between the ramus of the jaw and the internal lateral ligament, 

 beneath the insertion of the external pterygoid. This constitutes the 

 first part of its course, and from it are given off the tympanic, middle 

 and small meningeal, and the inferior dental branches. 



The tympanic branch mounts behind the condyle of the jaw to the 

 middle ear, which it enters by the Glaserian fissure. It forms an ana- 

 stomotic circle upon the membrane with the stylo-mastoid branch of 

 the posterior auricular. The middle meningreal enters the skull 

 through the foramen spinosum, passing between the heads of the 

 auriculo-temporal nerve (p. 63). It then divides. Its anterior 

 trunk runs in a tunnel or groove in the anterior inferior angle of the 

 parietal bone, and spreads in widely-reaching branches upon the convex 

 surface of the dura mater, and in grooves upon the frontal and 

 parietal bones. The posterior division winds backwards on the 

 squamous and parietal bones, to end, like the other, in the supply of 

 the dura mater and the cranium, and in anastomosis with its fellow 

 of the opposite side and other meningeal arteries. The middle 

 meningeal also gives a petrosal branch through the hiatus Fallopii, 

 which anastomoses in the aqueduct with the stylo-mastoid artery, 

 and sends branches through the great wing of the sphenoid into 

 the orbit and the temporal fossa. 



The small meningeal passes into the skull through the foramen 

 ovale. The inferior dental enters the dental canal,* and divides 

 opposite the first bicuspid into a mental and an incisive branch. The 

 former emerges by the mental foramen, and anastomoses with the 

 inferior labial and submental branches of the facial, whilst the other 

 continues in the lower jaw, supplying the canine and incisor teeth, 

 and meeting its fellow across the middle line. Before entering the 

 maxilla the inferior dental gives off the mylo-hyoid branch, which 

 ramifies on the cutaneous surface of the mylo-hyoid muscle. 



The second part of the artery lies in the triangle formed by the two 

 pterygoids and the ramus of the jaw ; it gives off deep temporal, 

 pterygoid, masseteric, and buccal branches. The anterior and pos- 

 terior deep temporals ascend b.eneath the temporal muscle, and ana- 

 stomose with the superficial and middle temporal arteries, and with 

 branches which enter the fossa from the middle meningeal and 

 ophthalmic arteries. As the masseteric twig runs outwards through 

 the sigmoid notch it supplies the maxillary joint. It anastomoses with 

 the facial and the transverse facial arteries. The buccal branch ana 

 stomoses upon the cheek with the facial. 



The third part of the artery enters the spheno-maxillary fossa 

 But just before doing so it gives off a trunk from which the alveola 

 and infra-orbital arteries arise. The alveolar, ox posterior dental, dis 

 tributes branches upon the tuberosity of the maxilla for the gums 



