172 ANIMAL DENTISTRY. 



with a chisel. When the fang is exposed throughout its 

 entire length the chisel is driven under the tooth and it is 

 pried out. 



The incisors of the solipeds and ruminants are seldom 

 decayed to the point requiring extraction. Longitudinal 

 fractures from falls or blows may loosen a part of an incisor 

 and provoke decay of the remaining portion, and occasion- 

 ally a persistent temporary with a long fang may demand 

 attention to improve the appearance of the mouth, but aside 

 from these instances extraction is seldom required. The 

 temporary incisors are frequently extracted to give the horse 

 the appearance of being one year older, or when the shed- 

 ding is delayed beyond the usual period. 



EXTRACTION OF THE CANINES OF HORSES. 



The deep, curved alveolar cavity of the horse's canines, 

 like the incisors, prevents forcep-extraction, in the young 

 animal. They are removed only in the recumbent posture, 

 by the removal of the external alveolar plate and prying 

 with the chisel as in the case of the incisor. 



The canines are seldom decayed except from pulpitis and 

 periostitis following injuries to the tooth or jaw. 



CARIES. 



Synonyms: — Caries dentium, decayed teeth, ulceration 

 of teeth. (It must not be confounded with alveolar perios- 

 titis of herbivora). 



Definition: — Caries signifies rotteness. As a diseased 

 process it might be appropriately defined as a biochemic de- 

 composition of the dentinal substance originating at one or 

 more points of a tooth. It might also be defined as a pro- 

 gressive disintegration of a tooth's substance, penetrating 

 from the surface toward the center. 



Etiology: — The exciting cause of caries is erosion or frac- 



