FUNDAMENTAL CONSIDERATIONS 



107 



Infundibulum 



Central enamel 

 Dentine 

 Peripheral 

 enamel 



Cement 



permanent incisors in each jaw is indicative of the age. 

 After this period the cups are relied upon to determine the 

 age up to eleven years. After this second period of develop- 

 ment the angle or slope of the teeth from the jaws and the 

 general appearance of the animal are the only guides. While 



some variations may occur in 

 the displacement of the tem- 

 porary teeth by the perma- 

 nent ones and in the rapidity 

 of the disappearance of the 

 cups, the appearance of the 

 teeth will show, within rea- 

 sonable limits, the age of 

 horses with normal mouths. 

 Temporary or Milk Teeth. 

 The age of young animals 

 may be determined by the 

 characteristic appearance of 

 the milk or temporary teeth, 

 which are twelve in number, 

 each jaw having six incisors. 



Peripheral enamel Cement 



Dentine - 

 Central enamel 

 Cement- 



FIG. 26. Longitudinal section of 

 lower incisor tooth of horse: C, pulp 

 cavity. Cement is shown in the 

 infundibulum, but is not marked.) 

 Courtesy of L. W. Sisson, from Ana- 

 tomy of Domestic Animals.) 



FIG. 27. Cross-section of lower 

 incisor tooth of horse: /, infundi- 

 bulum. (Courtesy of L. W. 

 Sisson, from Anatomy of Domestic 

 Animals.) 



The temporary teeth are slender, narrow, constricted at the 

 neck, and much whiter than the permanent teeth. The 

 permanent incisors are broader, thicker, and of a darker 

 color. The temporary incisors, which are all visible at one 

 year, remain intact until the two central temporary incisors 

 are replaced by the first pair of permanent central incisors. 



