TER YG OMANDIB ULAR REGION 



379 



by its deep surface, with the temporal fossa, the External 



muscles, the internal maxillary artery and its deep tem- 



ral nerves. Behind the tendon are the masseteric vessels 



vessels and nerve. Its anterior bonier is separated from 



i oral muscles are supplied by branches of the inferior 



: 



Disst 

 coronoid 

 detached t 



the condyle, and iil^i, 

 foramen; remftJfrAhf 



Pterygomandibular Region (Figs. 297, 298). 



Internal pterygoid. 



n examined, saw through the base of the 



irh the Temporal muscle, which should be 



1 )ivide the ramus of the mandible just below 



\\ <>\iciidiii<r across the middle, just above the dental 



'es will be exposed. 



FIG. 297. The Pterygoid muscles, the zygc 



havi 



of the mandible 



The External pterygoid muscle v '* :w) is a short, thick 



muscle, somewhat conical in form, which e i almost horizontally between the 

 zygomatic fossa and the condyle of the o heads, sepa- 



rated by a slight interval ; the upper head ar, 'rior surface of the greater 



wing of the sphenoid and from the pterygoid ..-parates the zygomatic 



from the temporal fossa; the lower head amr. ,< outer surface of the external 



pterygoid plate. Its fibres pass horizontally backward and outward, to be inserted 

 into a depression in front of the neck of the condyle of the mandible and into the 

 front of the articular disk of the temporomandibular articulation. 



Relations. By its superficial surface, with the ramus of the mandible, the internal maxillary 

 artery, which crosses it, 1 the tendon of the Temporal muscle, and the Masseter; by its deep 

 surface it rests against the upper part of the Internal pterygoid muscle, the internal lateral liga- 

 ment, the middle meningeal artery, and inferior maxillary nerve; by its upper border it is in 

 relation with the temporal and masseteric branches of the inferior maxillary nerve; by its lower 

 border it is in relation with the inferior dental and lingual nerves. Through the interval 

 between the two portions of the muscle, the buccal nerve emerges and the internal maxillary 

 artery passes, when the trunk of this vessel lies on the muscle (Fig. 293). 



1 This is the usual relation, but in many cases the artery will be found below the muscle. 



