442 INFERIOR MAXILLARY NERVE. 



the spheno-maxillary fissure, and divides into two branches, temporal 

 and malar ; the temporal branch ascends along the outer wall of the 

 orbit, and, after receiving a branch from the lachrymal nerve, passes 

 through a canal in the malar bone and enters the temporal fossa ; it 

 then pierces the temporal muscle and fascia and is distributed to the 

 integument of the temple and side of the forehead, communicating with 

 the facial and anterior auricular nerve. In the temporal fossa it com- 

 municates with the deep temporal nerves. The malar, or inferior 

 branch, takes its course along the lower angle of the outer wall of the 

 orbit, and emerges upon the cheek through an opening in the malar 

 bone, passing between the fibres of the orbicularis palpebrarum muscle. 

 It communicates with branches of the infra-orbital and facial nerves. 



The Two branches from Meckel's ganglion ascend from that body to 

 join the nerve, as it crosses the spheno-maxillary fossa. 



The Posterior dental branches pass through small foramina, in the 

 posterior surface of the superior maxillary bone, and running forwards 

 in the base of the alveolus, supply the posterior teeth and gums. 



The Middle and anterior dental branches descend to the correspond- 

 ing teeth and gums ; the former beneath the lining membrane of the 

 antrum, the latter through distinct canals in the walls of the bone. 

 Previously to their distribution, the dental nerves form a plexus (supe- 

 rior maxillary plexus) in the outer wall of the superior maxillary bone 

 immediately above the alveolus. From this plexus the filaments are 

 given off which supply the pulps of the teeth, the gums, the mucous 

 membrane of the floor of the nares, and the palate. Some gangliform 

 masses have been described in connection with this plexus, one being 

 placed over the canine, and another over the second molar tooth. 



The Muscular and cutaneous branches are the terminating filaments 

 of the nerve ; they supply the muscles, integument, and mucous mem- 

 brane of the cheek, nose, and lip, and form an intricate plexus with 

 branches of the facial nerve. 



The INFERIOR MAXILLARY NERVE proceeds from the inferior angle 

 of the Casserian ganglion ; it is the largest of the three divisions of 

 the fifth nerve, and is augmented in size by the anterior or motor 

 root, which passes behind the ganglion, and unites with the inferior 

 maxillary as it escapes through the foramen ovale. Emerging at the 

 foramen ovale the nerve divides into two trunks, external and in- 

 ternal, which are separated from each other by the external pterygoid 

 muscle. 



The External trunk* into which may be traced nearly the whole of 

 the motor root, immediately divides into five branches which are dis- 

 tributed to the muscles of the temporo-maxillary region ; they are 



The Masseteric, Avhich crosses the sigmoid notch with the masseteric 

 artery to the masse ter muscle. It sends a small branch to the tem- 

 poral muscle, and a filament to the temporo-maxillary articulation. 



Temporal; two branches passing between the upper border of the 

 external pterygoid muscle and the temporal bone to the temporal 



