BEANCHES OF THE EXTEENAL CAEOTID AETEEY. 899 



arteries. The anterior and posterior branches of the middle meningeal arteries and their 

 ramifications are separated from the bone by corresponding veins. 



(d) An accessory meningeal branch may arise either directly from the first part of 

 the internal maxillary or from its middle meningeal branch. It passes upwards, on the 

 medial side of the external pterygoid muscle, enters the middle fossa of the skull through 

 the foramen ovale, supplies the semilunar ganglion and the dura mater, and terminates 

 by anastomosing with branches of the middle meningeal and internal carotid arteries. 



(e) The inferior alveolar is a branch of moderate size which passes downwards, between 

 ', the spheno-mandibular ligament and the mandible, to the mandibular foramen. It is 



accompanied by the inferior alveolar nerve, which lies in front of it. After entering the 

 foramen it descends in the mandibular canal, and terminates at the mental foramen by 

 dividing into mental and incisive branches. 



Branches. Before it enters the mandibular foramen it gives off two branches. 



(i.) The lingual, a small twig, to the buccal mucous membrane, which accompanies the lingual 

 nerve, (ii.) The mylo-hyoid, a small branch which is given off immediately above the mandibular 

 foramen. It pierces the spheno-mandibular ligament, and descends in the mylo-hyoid groove, in 

 company with the mylo-hyoid nerve, to the floor of the mouth, where it anastomoses, on the 

 superficial surface of the mylo-hyoid muscle, with the submental branch of the external maxillary 

 artery. 



In the mandibular canal the following branches are given off : 



(i.) Molar branches to the molar teeth, (ii.) Premolar branches to the premolar teeth, (iii.) The 

 incisive terminal branch, which supplies the incisor and canine teeth and anastomoses with its 

 fellow of the opposite side, (iv.) The mental terminal branch, which passes through the 

 mental foramen, emerges beneath the quadratus labii inferioris, and anastomoses with its fellow 

 of the opposite side, with the inferior labial, and with the submental arteries. 



From the second part. (a) The masseteric, a small branch which passes laterally, 

 through the mandibular notch, to the deep surface of the masseter muscle. It 

 anastomoses in the substance of the muscle with branches of the transverse facial and 

 with the masseteric branches of the external maxillary artery. 



(6) Deep Temporal. Two in number, anterior and posterior. They ascend, in the 

 , temporal fossa, between the temporal muscle and the squamous portion of the temporal 

 bone, supplying the muscle and anastomosing with the temporal and lacrimal arteries, 

 and, through the substance of the temporal bone, with the middle meningeal artery. 



(c) Small pterygoid branches supply the internal and external pterygoid muscles. 



(d) The buccinator branch, a long, slender branch which passes obliquely forwards and 

 downwards with the buccinator nerve. It supplies the buccinator muscle, the skin and 

 mucous membrane of the cheek, and anastomoses with the buccal branches of the 



1 external maxillary artery. 



From the third part. (a) A posterior superior alveolar branch descends in the 

 1 infratemporal fossa, on the posterior surface of the maxilla, and ends in branches which 



supply the molar and premolar teeth and the mucous membrane of the maxillary sinus ; 



they also give twigs to the gums and to the buccinator muscle. 



(b) An infra-orbital branch commences in the pterygo-palatine fossa. It enters the 

 orbit through the inferior orbital fissure, and runs forwards in the infra-orbital groove 

 and canal to the infra-orbital foramen, through which it emerges on the face, deep to the 

 quadratus labii superioris. Whilst in the infra-orbital groove it gives branches to the 

 inferior rectus and the inferior oblique muscles and the lacrimal gland. In the infra-orbital 

 canal it gives small twigs to the incisor and canine teeth (aa. alveolares superiores 

 anteriores) and to the maxillary sinus. In the face it sends branches upwards to the 

 lower eyelid, to the lacrimal sac, and to the frontal process of the maxilla ; these anasto- 

 mose with branches of the ophthalmic and external maxillary arteries ; other branches 

 run downwards to the upper lip, where they anastomose with the superior labial artery ; 

 lastly, some branches run laterally into the cheek to unite with the transverse facial and 



\ the buccinator arteries. 



(c) The descending palatine runs downwards, through the pterygo-palatine fossa, enters 

 the pterygo-palatine canal, and becomes the great palatine artery, which supplies the 



> mucous membrane of the roof of the mouth. As it descends it gives off the artery of the 

 pterygeid canal, and several small twigs which pass through the accessory palatine canals 

 to supply the soft palate, and to anastomose with the ascending palatine and tonsillar 

 branches of the external maxillary and with the ascending pharyngeal artery. The great 

 palatine artery, which is the continuation of the descending palatine, runs forwards in the 

 roof of the mouth, medial to the alveolar process, to terminate in a small branch, which 

 ascends through the incisive foramen and anastomoses with the posterior artery of the 



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