APPLIED ANATOMY. 



The facial artery runs upward and inward, from a couple of centimetres in front 

 of the angle of the jaw, along the anterior border of the masseter muscle to the angle 

 of the mouth, and thence to the inner canthus of the eye. The anterior edge of the 

 masseter muscle can usually be distinctly felt beneath the skin. At this point the 

 vessel can be ligated or temporarily compressed by passing a pin beneath it and 

 winding a silk ligature above it, around the ends of the pin. This procedure is 

 desirable in some operations on the cheek, as angiomas frequently affect this region. 

 If the facial artery is ligated, the blood supply comes from the superior and inferior 

 coronary arteries of the opposite side; the nasal branch of the ophthalmic, anasto- 

 mosing with the angular; the transverse facial below the zygoma, from the temporal; 

 the infra-orbital, a branch of the internal maxillary ; and to a slight extent from the 

 inferior labial and others still less important (Fig. 58). 



The internal maxillary artery, one of the terminal branches of the external 

 carotid, arises in the parotid gland opposite the neck of the lower jaw. This is just 

 below and behind the articulation, which can be readily felt through the skin. It 



Muscular branches 



Superficial temporal 

 artery 



Sphenomandibular 

 ligament 

 Middle meningeal 



. External carotid--- 

 Inferior alveolar (dental) 



Infra-orbital 



Superior alveolar 

 (posteriordental) 



External ptery- 

 goid muscle 

 Internal ptery- 

 goid muscle 



Buccal nerve 

 Lingual nerve 



Inferior alveolar 

 nerve 



FIG. 59. The internal maxillary artery. 



passes between the bone and the sphenomandibular (long internal lateral) ligament, 

 then between the two pterygoid muscles or between the two heads of the external 

 pterygoid muscle to the posterior surface of the superior maxillary bone in the 

 sphenomaxillary fossa. The branches of its first part, where it is behind the neck of 

 the jaw, are the deep aiiricular, tympanic, middle and small meningeal, and inferior 

 alveolar (dental}. The branches of its second part, as it passes between the ptery- 

 goid muscles, are all muscular : they are the masseteric, pterygoid, anterior and 

 posterior deep temporal, and the buccal. The branches of the third portion of the 

 artery, in the sphenomaxillary fossa, are the posterior dental, infra-orbital, descending 

 palatine, Vidian, pterygopalatine, and spheno- or nasopalatine . 



The main trunk of the internal maxillary artery is not often involved either by 

 injury or operations. The various branches are, however, of considerable impor- 

 tance, as they supply parts which are often the site of operative measures. The 

 importance of the middle meningeal artery in reference to fractures of the skull has 

 already been pointed out. The inferior alveolar gives rise to troublesome hemorrhage 

 when the lower jaw is operated on. The deep temporal branches bleed freely when 

 the temporal muscle is incised in operating on the Gasserian ganglion. The infra- 

 orbital is involved in operating on the infra-orbital nerve. The posterior or descending 

 palatine branch descends in the posterior palatine canal, in company with a branch 



