English for medical students (the third course) (учебно - методическое пособие)
Recent investigations have shown various biologic activities within tooth structure. The enamel, dentin and pulp are connected hydro dynamically. The tooth (enamel and dentin) might be compared with a pipe that extends into the pulp at one end and into the oral cavity at the other end. The fluid may move in either direction depending on the forces applied to it. The direction that this fluid moves has important implications for the health of the tooth.
This is not a difficult process to visualize when one considers the tubular structure of dentin. However, it is interesting to note that a similar fluid transport system can also be seen in the enamel. Enamel contains minute pores within its crystalline structure. These pores permit fluid exchange between the dentin and the oral cavity.