VE TERINAR Y DENTAL SURGED Y. 



95 



tained a great size. These tubercles have the color, 

 density and structure of cementum. In some in- 

 stances the color 

 varies, assuming a 

 yellow tinge. Such 

 exostoses are usu- 

 ally harder than the 

 lighter colored ones. 

 In the human sub- 

 ject the deposition 

 of osseous material 

 is so extensive as to 

 involve two or more 

 teeth which become 

 thoroughly united. 

 This condition I 

 have never observed 

 in the domestic animals, with but a single excep- 

 tion; that being where the sixth and seventh lower 

 right molars of a hog had become firmly united, 

 resembling a single tooth. 



CAUSE. 



Some attribute it to external injury; others to 

 irritation of the periosteum surrounding the root. 

 The tooth from which the above drawing was made 

 is perfectly sound and does not show any signs of 

 ever having been diseased. I am inclined to think it 

 is due to a constitutional diathesis following the same 



FIG. 24. 



SECOND UPPER MOLAR. 



Showing an exostosis a, b, on both 

 sides, two-thirds natural size. 



