232 



THE ARTICULATIONS. 



parallel with one another, and directed obliquely downward and backward. Ex- 

 ternally, it is covered by the parotid gland and by the integument. Internally, 



FIG. 157. Temporo-mandibular articulation. External view. 



it is in relation with the capsular ligament, of which it is an accessory band, and 



not separable from it. 



The Internal Lateral Ligament (Spheno-mandibular) (Fig. 158) is a flat, thin 



band which is attached above to the spinous process of the sphenoid bone, and, 



becoming broader as it descends, is 

 inserted into the lingula and margin 

 of the dental foramen. Its outer 

 surface is in relation, above, with 

 the External pterygoid muscle ; 

 lower down it is separated from 

 the neck of the condyle by the in- 

 ternal maxillary artery ; and still 

 more inferiorly, the inferior dental 

 vessels and nerve separate it from 

 the ramus of the jaw. The inner 

 surface is in relation with the In- 

 ternal pterygoid. It is really 

 the fibrous covering of a part of 

 Meckel's cartilage. 



The Stylo -mandibular Ligament 

 is a specialized band of the cervi- 

 cal fascia, which extends from near 

 the apex of the styloid process of 

 the temporal bone to the angle and 

 posterior border of the ramus of 



FIG. 158. Temporo-mandibular articulation. Internal view, the lower jaw, between the MaSS6- 



ter and Internal pterygoid muscles. 



This ligament separates the parotid from the submaxillary gland, and has attached 

 to its inner side part of the fibres of origin of the Stylo-glossus muscle. Although 



