OSTEOLOGY. 29 



THE INFERIOR MAXILLA is the largest bone in the face. It 

 consists of a body and two rami. 



The body is the horizontal, horseshoe-like portion, contain- 

 ing the lower teeth. 



The external surface presents from before backward : 



Symphysis, a vertical median line indicating the junction of 

 the vaginal halves ; 



Mental process, a triangular prominence constituting the 

 chin; 



Incisive fossa, for the origin of the levator labii inferioris ; 



Mental foramen, for the exit of the mental nerve and artery; 



FIG. 14. 



1, body; 2. ramus; 3, symphysis; 5, mental foramen; 6, external 

 oblique line; 7, facial groove; 8, angle; 9, internal oblique line; 10, 

 coronoid process; 11, condyle; 12, sigmoid notch; 13, inferior dental 

 foramen; mylo-hyoid groove; i, incisors; c, canine; b, bicuspids; 

 m, molars. 



External oblique line, running backward and upward from 

 the mental process, for the attachment of the depressor anguli 

 oris and depressor labii inferioris. 



The internal surface presents from before backward : 



Genial tubercles, four in number, for attachment of the 

 genio-hyoglossi muscles above and the genio-hyoidei below; 



Sublingual fossa, for the sublingual gland; 



Internal oblique line (mylo-hyoidean), fot the attachment 

 of the superior constrictor, the mylo-hyoid muscles, and the 

 ptery go-maxillary ligament ; 



Submaxillary fossa, for the submaxillary gland. 



The superior or alveolar border presents sixteen cavities (ten 

 in childhood) for the teeth. 



The inferior border is grooved posteriorly for the facial 

 artery. 



