10 VETERINARY DENTAL SURGERT. 



as the maxillary hiatus, and which contains three 

 foramina; the first leads to the palatine groove giv- 

 ing exit to the palatine artery, the second enters the 

 maxillary sinus passing along the roots of the molar 

 teeth and dividing into two branches; one short and 

 wide which opens on the external surface of the 

 bone on a level with the third molar tooth, the other 

 continues along the canal of the bone to the roots of 

 the incisor teeth. The third, the palatine canal, enters 

 the nasal chambers and gives passage to blood vessels 

 and nerves. The anterior extremity of this bone 

 with the posterior extremity of the pre-maxilla 

 forms a cavity in which the canine tooth is lodged. 

 The pre-maxilla bone (Fig. i- 1) occupies the anter- 

 ior extremity of the face, and consists of a thick por- 

 tion and two processes. The thick portion presents 

 three surfaces, the external or labial, which is smooth 

 and convex ; an internal, which is roughened to artic- 

 ulate with its fellow on the opposite side, and is 

 traversed by a fissure, which forms with the bone of 

 the opposite side, the foramen incisivum, for the pas- 

 sage of the palato-labial artery ; and an inferior, 

 which is smooth and slightly concave and shows the 

 continuation of the palatine fissure which opens into 

 the foramen incisivum. Between the external and 

 inferior surface is a thick border which is divided into 

 two parts, an anterior and posterior ; the anterior 

 contains three alveoli, which receive the incisor teeth. 



