STRUCTUKE OF DENTINE. 



467 



canals, having walls of a peculiar nature the dentinal sheaths 

 in which lie the dentinal fibres. The dentinal canals com- 

 mence with small circular openings on the inner surface of the 

 pulp cavity, and pass radially outwards through the dentine, 

 making numerous spiral turns in their course (Welcker, 41). 



Fig. 98. 



Fig. 98. Canine tooth of Man, presenting a portion of the transverse 

 section of the root. 1. Cement with large lacunae and parallel striae. 

 2. Interglobular substance. 3. Dentinal tubules. Magnified 300 

 diameters. 



As a general rule each tubule extends from the pulp cavity to 

 the enamel, or cement, giving off in its course numerous 

 delicate transverse branches. By means of these transverse 

 branches both the tubules and their contents the dentinal 

 fibres anastomose with each other. In sections made from 



