POSITION OF VESSELS AND NERVES. 



89 



of the jaw. In removing the fatty tissue, the student must be careful not 

 to take away the thin lateral ligament, which lies on the internal pterygoid 

 muscle beneath the ramus. 



Position of vessels. Crossing inwards over the external pterygoid 

 muscle, is the internal maxillary artery, which distributes offsets upwards 



SUPERFICIAL VIEW OF THE PTERYGOID REGION (Quain's "Arteries"). 



1. Temporal muscle. 6. Common carotid dividing into external and 



2. External pterygoid. internal trunks. 



3. Internal pterygoid. 8. Internal maxillary artery (beneath the 



4. Buccinator. pterygoid instead of over it) and its 



5. Digastric and stylo-hyoid muscles cut and branches. 



thrown back. The nerves are omitted in this woodcut. 



and downwards: sometimes the artery will be placed beneath the muscle. 

 The veins with the artery are large and plexiform: and may be taken 

 away. 



Position of nerves. Most of the branches of the inferior maxillary 

 nerve appear in this dissection. Thus, issuing from beneath the lower 

 border of the external pterygoid are the large dental and gustatory nerves, 

 the latter being the more internal of the two; and coming out behind the 

 joint of the jaw is the auriculo-temporal nerve. Appearing between the 

 upper border of the muscle and the cranium, are the small masseteric and 

 deep temporal nerves. The buccal branch of the nerve perforates the fibres 

 of the same muscle near the inner attachment. Branches of the above- 

 mentioned artery accompany the nerves. Coursing along the posterior 

 part of the upper jaw, is the small posterior dental nerve with an artery. 



Between the jaws is the whitish narrow band of the pterygo-maxillary 

 ligament, to which the buccinator and superior constrictor muscles are 

 connected. 



The EXTERNAL PTERYGOID MUSCLE (fig. 18, 2 ) extends almost horizon- 

 tally from the zygomatic fossa to the neck of the lower jaw. Its origin is 



