242 VETERINARY LECTURES 



grain. A bit of stone, a piece of iron, or a nail may have got into 

 corn and caused the injury. By removing the loose portion of the 

 tooth the animal generally does well, but, in time, the tooth opposite 

 becomes elongated, owing to its not meeting sufficient wearing 

 surface, and has to be cut off, or dressed down with a tooth-rasp. 



357. It is said by some writers that teeth grow ; to a certain 

 extent this is true, but at six years old all the teeth are fully 

 developed, after which period they gradually wear away. This is 

 well exemplified by the incisors, or nippers, becoming triangular as 

 they wear down, when their crowns take the shape of the fang or 

 root. Teeth, however, become elongated when they are not made 

 use of, owing to the tooth opposite becoming decayed or removed. 

 As a proof that they wear, and do not grow, see Plate XXXI., Nos. 1 

 and 2, which shows the upper molar of a six-year-old horse and one 

 of a horse twenty-six years of age. Damaged teeth are, however, most 

 likely to become carious . I have come across a few of this nature, 

 but, in young animals, as already stated, I think the disease more 

 frequently commences in the alveolar processes (bone-plates) and 

 sinuses, finally implicating the teeth themselves. Disease of the 

 teeth of the horse is not very common, but when a diseased tooth is 

 present the animal generally quids its food — i.e., chews it, and then 

 lets it drop out of the mouth in small pellets ; in such cases the 

 tooth has is be removed. 



358. With the forceps I have had made (Plate XXXI 1 1., No. 3), 

 and which I find to be an improvement upon Professor Pritchard's, 

 by the addition of the screw and longer leverage, I can, in a few 

 minutes, remove any molar, either from the upper or the lower jaw. 

 In extracting a tooth, I have the animal cast, but have a great 

 objection to casting aged horses with ' hobbles.' I prefer side-lines 

 in these latter cases. I do not use chloroform, unless specially 

 requested to do so, as I think it is not necessary. After removing the 

 tooth, I always dress the hole every third day by plugging with tow 

 saturated with three parts water and one part tincture of iron, which 

 answers splendidly, finally filling it with gutta-percha. In one case 

 the diseased bone was so great, extending through into the nostril, that 

 it took 4 ounces to fill the cavity. The horse in question did well 



