THE MAXILLARY BONES. 



25 



verse septa, the sockets of the teeth being formed by the 

 interspaces between these septa. The internal alveolar plate 

 is the stronger, the external the thinner and weaker, a fact 

 of which we take advantage when we extract a tooth by 

 bending it slightly outwards. On the outer surface of the 

 alveolar process are eminences corresponding to the roots 

 of the teeth, and depressions in their interspaces, apt to be 



FIG. 12 ('). 



especially marked over the canine teeth ; while between 

 the teeth the alveolar processes attain to a lower level, so 

 that the margins of the bone are festooned. Looking 

 down into an empty socket, the bone is seen to be every- 

 where very porous, and to bo perforated by foramina of 

 considerable size, while at the bottom there is the larger 

 foramen admitting the vessels and nerves of the tooth. 



The alveolus of each individual tooth consists of a shell of 

 comparatively dense bone of small thickness, which is im- 

 bedded in a mass of loose spongy bone; this dense shell 

 comes into relation with the dense cortical bone of the jaw 



(*) Superior maxillary bone of right side. 1. Body. 2. Tuberosity. 

 7. Malar process. 8. Nasal process. 12. Alveolar process. 



