PRECAUTIONS IN EXTRACTING HORSE^ TEETH. 51 
last the tooth should be pushed hack, if possible ; or if this is impracticable, the 
opening of the gag must be diminished, and the jaw pushed sideways in the 
direction of the displaced tooth. 
Sometimes room is wanting between the upper and lower rows of teeth. 
Should the size of the forceps be to blame, they should be changed ; where the 
opposite tooth is too long, it must be cut shorter or removed. In placing the 
forceps in position, care is required not to grasp more than the diseased tooth. 
In extracting pre-molars, one hand is introduced into the mouth to guide the 
instrument. The displacement of the tooth often simplifies the determination 
of its position and the adjustment of the forceps. In using the Frick-Hauptner 
forceps (fig. 26), the correct position is assured by counting the teeth in front 
of the jaws of the instrument. 
( b ) Teeth that are still firm can be loosened by light side movements of the 
instrument. But to avoid breaking the crown of the tooth or fracturing the 
jaw, it is needful to proceed slowly and cautiously. 
(c) Adjustment and selection of the fulcrum. —When using a first-class lever 
forceps, as already stated, the selection of the fulcrum must be made with a 
knowledge of the general direction of the axis of the tooth, to which the 
fulcrum should be brought as near as possible, in order to give greater 
leverage. 
(d) Noio follows the extraction of the tooth— The operator takes up a farm 
position, with his elbows on his sides, and giving the word to hold fast, exei- 
cises a steady but strong pull on the forceps, throwing on them the weight 
of the body. The power required to draw a tooth in the prone subject is 
developed by the muscles of the thigh, the power of the arms not being 
usually sufficient. The arms, or rather the hands, are employed in grasping 
the limbs of the forceps, so as to retain hold of the tooth. 
Should the attempt be successful, the tooth is felt to yield, and a hissing 
noise may sometimes be heard, due to the air rushing into the alveolus. In 
such case the tooth is still firmly held, but the pull is lelaxed foi an instant. 
A deeper fulcrum is slipped under the forceps, and a light pull will now 
generally remove the tooth. As in young animals the teeth aie longei, a fiesh 
and deeper hold is often needful. Short teeth can be removed directly with 
the forceps, but longer ones may require the assistance of the hand 01 expoi- 
teur (fig. 22). The opposite teeth sometimes prevent removal of the loosened 
molar. & In such cases more room must be made, either by opening the gag 
further, or by closing it and pushing the lower jaw to one side, in order that 
the two rows of teeth no longer oppose each other. The tongue, however, 
should not be loosened, for fear of the tooth falling into the mouth and being 
swallowed. , , , 
If, during extraction, the animal makes violent movements with tfae faeaci, 
the operation is stopped, but the movements are followed by the forceps. 
This is especially necessary when operating on horses standing. If the 
forceps are held rigidly, the jaw may easily be fractured by the animal s own 
movements. , 
If the forceps are not firmly held they may slip oft the tooth and require to 
be readjusted. Should this happen repeatedly, and, even after considerable 
efforts, no loosening of the tooth occur, endeavour must be made to discover 
the cause of failure, which most frequently results from an improper hold 
having been taken, the pull being in a wrong direction, or several teeth being 
grasped. A change of forceps or of pivot is often desirable. It may be 
repeated, that the direction of pull should correspond w ith the axis of the 
tooth, otherwise power is lost by the tooth grasped being forced against 
its neighbour. In certain cases, like dental fistula, growths, either in the 
alveolus or on the tooth, render extraction very difficult, oi even impossible. 
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