168 



DISEASES OF 



*THE GROWTH AND WEAR OF TEETH. 



Healthy horses' teeth (the second set, not the first), 

 grow practically throughout life, but much slower after 

 fifteen or sixteen years of age 

 than before. This growth is 

 designed by nature to counter- 

 act the enormous wear of the 

 teeth, the horse having to 

 perform for hinself that which 

 the miller performs for man. 

 If the lower molar, illustrated 

 in figure 59, had met its 

 corresponding upper molar, 

 its two inches of extra growth 

 should have been worn off by 

 attrition (mastication) and a 

 like amount from the upper 

 tooth. But the upper tooth 

 was unfortunately lost. The 

 lower tooth therefore, grew till 

 the friction from it on the 

 upper jaw killed the horse. 

 Various kinds of instruments 

 are used to remove this extra 

 growth of teeth. A moderately 

 sharp chisel may be used, but 

 there is danger of its slipping 

 and cutting the soft structures 

 of the mouth or throat, for it 

 has to be struck with considera- 

 ble force. When convenient send for a veterinary den- 



Fig. 59. Back lower molar 



extra growth begins at 



dotted line. 



* Thia page is from " Horse's Teeth," by W. H. Clarke. 



