58 SURGICAL ANATOMY OF 



the raraus) carefully lifted up, with the attached tem- 

 poral muscle; some fibres of this muscle must be di- 

 vided in order to do this, and as the buccal nerve and 

 artery usually lie immediately beneath them, some cau- 

 tion is necessary in order to avoid their division. 



Contents. Immediately beneath the bone thus raised, 

 are seen a portion of the internal maxillary artery, the 

 external pterygoid muscle, and emerging from its lower 

 border the gustatory branch of the third division of the 

 fifth, the mylo-hyoidean branch of the inferior dental 

 nerve, part of the internal pterygoid muscle, the trunk of 

 the inferior dental and deep temporal nerves, the inter- 

 nal lateral ligament of the temporo-maxillary articula- 

 tion, and in front of the internal pterygoid the posterior 

 portion of the buccinator. 



The vessels of this region are, in the superficial dissec- 

 tion, the transverse facial or external maxillary, which 

 arises from the external carotid in the parotid gland, 

 just above the angle of the jaw, and in relation with the 

 portio dura and Steno's duct, crosses the masseter a lit- 

 tle below the zygoma. 



In the deep dissection the internal maxillary artery 

 commences at the outer border of the neck of the jaw- 

 bone, lying in the first part of its course behind it, and 

 in front of the internal lateral ligament; it then curves 

 forwards to the lower border of the external pterygoid 

 muscle, lying on it, and, generally disappearing between 

 its two heads, passes into the pterygo-maxillary fossa. 

 The trunk of this vessel or its descending branch, the 

 inferior dental, are usually divided in resection of the 

 bone. Its tortuous course and variable position render 

 it the more liable to be wounded. 



The nerves are derived from the inferior maxillary di- 



