318 VETEKINARY MEDICINE AND SURGERY. 



length. — Again, as age increases, the teeth, notwithstanding they 



Fig. 157. 

 Triangular shape of teeth at sixteen years. 



really wear down, become apparently longer. This effect is due to the 

 fleshy parts of the gums receding faster than the teeth wear down. In 



Fig. 158. 

 Triangular shape of teeth at twenty years. 



extreme age, however, when the gums have receded as far as they can. 



Fig. 159. 

 Triangular shape of teeth at twenty-four years. 



the effect of wear causes the teeth to become visibly as well as really 

 shorter. 



Fig. 160. 

 Shape of tooth crowns in old age. 



