24 A MANUAL OF DENTAL ANATOMY. 



While full description of these bones ( ! ) will be found in any 

 general anatomical work, there are so many points in their 

 anatomy which directly concern the dental student that a 

 brief enumeration of some of their relations can hardly be 

 dispensed with. 



Superior maxillary bone. To facilitate description of 

 its parts, anatomists divide it into a "body" and "pro- 

 cesses," of which latter there are four, the nasal, malar, 

 alveolar, and palatine. As the body of the bone is hollowed 

 out by an air cavity, the antrum, its shape is similar to that 

 of that cavity, namely, roughly pyramidal, the base of the 

 pyramid being inwards towards the nasal chamber. 



The nasal process springs directly upwards from the body 

 in a vertical line with the canine tooth : it is a strong plate 

 of bone, roughly triangular when viewed from the side. 



The malar process forms the apical portion of the pyramid 

 already alluded to ; it starts out nearly horizontally from 

 the body just behind and below the nasal process, and is 

 characterized by its great strength and stoutness. Never- 

 theless it has been known to be fractured by a blow, and 

 separated from the body of the bone. The antrum may be 

 prolonged into it. 



The palatine process forms a horizontal table projecting 

 inwards from the body; as the floor of the nose is nearly flat, 

 and the palate is arched from before backwards, the front of 

 the palatine process is necessarily much thicker than the 

 back, where it is quite a thin plate. 



The alveolar process is a strong wide ridge of bone, curved 

 so as to form with that of the other maxillary bone the 

 elliptical figure characteristic of the dental arch in the higher 

 races. It may be described as consisting of two plates, an 

 outer and an inner, which are connected by numerous trans- 



(!) Much that is of great interest, and that is not to be found in text 

 books, is embodied in a series of papers on " The Facial Region," by Dr. 

 Harrison Allen (American Dental Cosmos, 1873-74). 



