344 



OPEKATIOXS ON THE DIGESTIVE APPAEATUS. 



Fig. 347.— Garangeot's Keys. 



less puslied out of its place by a succeeding growtli, is seized be- 

 tween the jaws of the forceps, or of the Garangeot's keys, and is 

 easily wrenched from its position by a strong pull or with a sUght 

 twisting motion sufficient to lacerate its last adhesions. 



The extraction of the permanent molars of a horse is a diffi- 

 cult and, under some circumstances, a serious operation. Their 

 mode of implantation and insertion in the alveolar cavities ; the 

 great length of then- roots as compared to the small dimensions 

 of their free portion; the narrow connections which exist be- 

 tween them, and withal, the solidity of the dental arch — all these 

 conditions are sufficient to explain the serious character of the 

 prognosis of this ox^eration, and the difficulties which are often 

 encountered when the organ to be removed is the molar tooth of 

 a horse. These difficulties, however, vary considerably under -pe- 

 culiar conditions, such, according to Peuch & Toussaint, as " the 

 age of the subject, the position of the tooth on one or the other 

 jaw, and the degree of alteration of the tooth to extract." 



For examjole, the operation is more difficult in young animals 

 than in adult, or older subjects, the latter requmng less effort, 

 the root of the tooth being shorter and the adhesion to the alveola 

 less solid. The upper are less firmly attached than the lower 



