54 PRACTICAL ANATOMY. 



plate, articulates with the inferior turbinated crest of the 

 superior maxillary, with the lachrymal and ethmoid. 

 Posterior to the vertical plate, it articulates with the 

 inferior turbinated crest of the palate. The inferior 

 turbinated develops by a single centre, which appears 

 about the fourth month. 



THE INFERIOR MAXILLARY. 



The inferior maxillary is an irregular bone which 

 forms the lower jaw. It is the strongest and largest 

 bone of the face, and consists of a body and two rami. 

 The body, placed horizontally, is bent like a horseshoe ; it 



FIG. 25. INFERIOR MAXILLARY BONE. 



is a thick plate of bone, curved on the flat, and presents 

 for examination an external and internal surface, a 

 superior and inferior border. The external surface is 

 strongly convex from side to side, and, in front, concave 

 from above downward. It is somewhat rough and 

 irregular, and presents in the median line a ridge, which 

 indicates the line of union (symphysis) between the two 

 halves of the bone. This ridge expands near the inferior 

 border in a triangular, slightly-elevated mass of bone, 

 the mental process. On each side of the ridge, beneath 

 the incisor teeth, is a shallow depression, the incisive 

 fossa, which gives origin to the levator menti muscle. 



