INFERIOR MAXILLARY NERVE. 



95 



Directions. Should the internal maxillary artery obstruct the view of 

 the nerve, it may be cut through. 



The SMALLKK PART, formed mainly by its contribution from the trunk 

 of the nerve, receives nearly all the fibrils of the motor root, and ends in 

 branches for the muscles of the jaw, viz., temporal, masseter, and one ptery- 

 goid ; and for the muscle of the cheek, the buccinator. 



Fig. 21. 



DEEP VTEW OF THE PTKRYGOID KEGION (Illustra- 

 tions of Dissections). 



Muscles : 

 a. Temporal reflected. 

 6. Condyle of the jaw disarticulated with 

 the external pterygoid attached to it. 



c. Internal pterygoid. 



d. Buccinator. 



/. Mass< ter thrown down. 

 Nerves : 



1. Buccal. 



2. Masseteric, cat. 



3. Deep temporal. 



4. Auriculo-temporal. 



6. Chorda tympani. 



7. Inferior dental. 



8. Gustatory. 



10. Internal lateral ligament of the lower 

 jaw. The arteries are not figured, 

 with the exception of the internal 

 maxillary trunk which is marked 

 with 9 : the offsets of the artery ac- 

 company the nerves, being named 

 like them. 



The deep temporal branches ( 3 ) are furnished to the under surface of the 

 temporal muscle. Like the arteries, they are two in number, anterior and 

 posterior, and course upwards beneath the external pterygoid muscle. 



The posterior branch is the smallest, and is often derived from the 

 masseteric nerve ; it is placed near the back of the temporal fossa. 



The anterior branch supplies the greater part of the muscle, and com- 

 municates sometimes with the buccal nerve. 



The masseteric branch ( 2 ) takes a backward course above the external 

 pterygoid muscle, and through the sigmoid notch, to the under surface of 

 the masseter muscle : in the masseter the nerve can be followed to near 

 the anterior border. As this branch passes by the articulation of the jaw 

 it gives one or more twigs to that joint. 



The pterygoid branches come from both parts of the inferior maxillary 

 nerve. 



The branch or branches to the external pterygoid spring from the small 

 part, or from the buccal nerve, and enter the under surface of its muscle. 



The nerve to the internal pterygoid arises from the large part of the 

 maxillary trunk close to the skull, and may be followed beneath the upper 

 border to the deep surface of the muscle; it will be learnt in the dissection 

 of the otic ganglion (SECTION 14). 



The buccal branch C 1 ), longer and larger than the others, perforates the 

 external pterygoid, and is directed inwards, beneath the coronoid process 

 to the surface of the buccinator, where it ends in terminal branches. As 

 it perforates the pterygoid muscle filaments are given to the fleshy sub- 



