126 LIGAMENTS OF THE LOWER JAW. 



The external lateral ligament is a short and thick band of fibres, 

 passing obliquely backwards from the tubercle of the zygoma, to the 

 external surface of the neck of the lower jaw. It is in relation, ex- 

 ternally with the integument of the face, and internally with the two 

 synovial membranes of the articulation and the interarticular cartilage. 

 The external lateral ligament acts conjointly with its fellow of the op- 

 posite side of the head in the movements of the jaw. 



The internal lateral ligament has no connection with the articulation 

 of the lower jaw, and is incorrectly named in relation to the joint ; it 

 is a thin aponeurotic expansion extending from the extremity of the 

 spinous process of the sphenoid bone to the margin of the dental fora- 

 men. It is pierced at its insertion, by the mylo-hyoidean nerve. 



A triangular space is left between the internal lateral ligament and 

 the neck of the jaw, in which are situated the internal maxillary 

 artery and auricular nerve, the inferior dental artery and nerve, and 

 a part of the external pterygoid muscle ; internally it is in relation 

 with the internal pterygoid muscle. 



The capsular ligament consists of a few irregular ligamentous fibres, 



Fig. 58.* 



which pass from the edge of the glenoid cavity to the neck of the 

 lower jaw, upon the inner and posterior side of the articulation. These 

 fibres scarcely deserve consideration as a distinct ligament. 



The interarticular fibrotis cartilage is a thin oval plate, thicker at the 

 edges than in the centre, and placed horizontally between the head of 

 the condyle of the lower jaw and the glenoid cavity. It is connected 



* An internal view of the articulation of the lower jaw. l. A section 

 through the petrous portion of the temporal bone and spinous process of the 

 sphenoid. 2. An internal view of the ramus, and part of the body of the lower 

 jaw. 3. The internal portion of the capsular ligament. 4. The internal lateral 

 ligament. 5. A small interval at its insertion through which the mylo-hyoidean 

 nerve passes. 6. The stylo- maxillary ligament, a process of the deep cervical 



