EXTRACIION OF TEETH. 7 



as it should be, one hand placed in the interdental space 

 with the dorsal surface against the jaw and the volar grasp- 

 ing the instrument, will serve as an effective fulcrum. 



In other cases an iron or steel fulcrum is not essential, 

 but a stick of hard wood of proper size and form acts quite 

 as efficientlj' and may even keep its position better because 

 the teeth upon which it rests sink into it somewhat. On 

 the whole the fulcrum is not so important as some have 

 considered it, since, after a tooth is loose enough to be 

 drawn with its aid, a very trifling additional loosening will 

 permit it to be easily lifted from its alveolus without it. 



The tooth fang is extracted by forcing the handles of the 

 forceps toward the jaw in which it is located, so that as it 

 is gradually drawn out the forceps tend to pivot on the 

 fulcrum in a way to permit the tooth to emerge from its 

 alveolus in the direction of its long axis. By referring to 

 Plate II it will be seen that the long axes of the different 

 teeth vary, that of the molars being obliquely forwards from 

 fang to crown towards the incisors, while the crowns of the 

 premolars are directed obliquely backwards toward the 

 molars. The slant of the teeth is most marked at the ends. 

 of each arcade while at the middle they acquire an almost 

 perpendicular position. 



In drawing the last molar the back of the forceps will, 

 generally strike against the opposite dental arcade before 

 the tooth has completely emerged from its alveolus and im 

 order to complete its removal it may be necessary to take 

 a deeper hold with the extracting forceps or withdrawing 

 these complete the operation with the aid of exporteur 

 forceps, or still better frequently with the hand. In young 

 horses where the teeth are very long we have found it im- 

 possible to complete the extraction until the tooth had been 

 divided transversely by means of the tooth cutting forceps. 



The dangers in the extraction of teeth are chiefly : 



I. The transverse fracture of the tooth, leaving the fang 

 still fixed in the alveolus, a danger not infrequently un- 



