THE TEMPORO-MAXILLARY JOINT. 



fill 



Its deep surface is in relation with the superior pharyngeal constrictor 

 below, and the tensor palati above. The origin of this muscle 

 embraces the lower part of that of the external pterygoid. 



Action. It acts with the masseter in raising the mandible. use. 



TEMPORO MAXILLARY ARTICULATION (figs. 220 and 221, p. 612). Joint of 

 This articulation is a compound joint, being formed by the condyle lo 

 of the lower jaw and the fore part of the glenoid cavity of the 

 temporal bone, with an interposed disc of fibro cartilage. The 

 bones are united by the following ligaments : 



The capsule is a thin membranous tube which is attached above Capsule of 

 to the temporal bone around the articular surface, and below to ejou 

 the condyle of the lower jaw, reaching farther down behind than 

 in front. The cavity in the interior is divided into two parts, 



Posterior deep temporal 



nerve. 

 Middle deep temporal 



nerve. 

 Anterior deep temporal 



nerve. 



External pterygoid : 



Communication with 

 facial nerve. 



Auriculo- temporal nerve. 



Chorda tympani. 



Lingual nerve. 



Inferior dental nerve. 



Branch to ex- 

 ternal pterygoid. 



Long buccal nerve. 

 Internal pterygoid. 



FIG. 219. DIAGRAM SHOWING THE RELATIONS OF THK BRANCHES OP THE 

 INFERIOR MAXILLARY NERVE TO THE PTERYGOID MUSCLES. 



upper and lower, by the nbro-cartilage ; and the upper portion of 

 the capsule is wider and looser than the lower. 



The external lateral ligament is a thickened band of the capsule, External 

 composed of fibres passing from the tubercle at the root of the lateral) 

 zygoma and the adjoining part of the outer surface of that process 

 to the outer and posterior part of the neck of the lower jaw. 



The internal lateral ligament (fig. 220, i) is a long, thin, mem- aild internal 

 branous band, which is not in contact with this joint. Superiorly ligament, 

 it is connected to a ridge on the inner side of the glenoid fo- 

 formed by the spinous process of the sphenoid and the vaginal 

 process of the temporal bone ; and inferiorly it is inserted into the 

 inner margin of the dental foramen in the lower jaw. The 

 ligament lies between the jaw and the internal pterygoid : and its 

 origin is concealed by the external pterygoid muscle. The internal 



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