CHAPTER IX 



THE SUPERIOR MAXILLARY DIVISION OF THE 



FIFTH NERVE. THE BLOOD AND LYMPH 



VESSELS 



THE SUPERIOR MAXILLARY DIVISION OF THE 

 FIFTH CRANIAL NERVE 



This is one of the sensory divisions of the fifth nerve. It leaves the 

 gasserian ganglion and passes out of the cranial cavity by the foramen 

 rotundum, which in the mascerated skull is easily recognised as the 

 most posterior of the foramina forming the orbital hiatus. The 

 foramen rotundum is in close proximity to the inferior opening of the 

 subsphenoidal canal, and since the internal maxillary division of the 

 external carotid artery passes through the latter, it will be seen how this 

 artery comes to run in close proximity to this branch of the fifth nerve. 

 The nerve crosses the lower and posterior part of the orbit, and gains 

 the maxillary hiatus. Having given off a number of branches, the main 

 portion of the nerve now passes into the superior dental canal and gives 

 off a large branch, which appears on the face through the infra-orbital 

 foramen and under cover of the levator labii superioris proprius muscle. 

 It then divides into superior, middle, and inferior branches, which form 

 intricate plexuses with branches of the seventh nerve (which is motor), 

 and are distributed to the true and false nostrils, upper lip, and to the 

 muscles and skin of the face. 



