PULP CHAMBER ANATOMY
Understanding normal internal tooth anatomy and its variations is essential for a clinician. As the external morphology of the tooth changes, so does the internal morphology.
Pulp cavity/space is a central cavity within the tooth; it is entirely enclosed by dentin except at the apical foramen. The coronal portion of this space is called pulp chamber, the radicular portion - root canal.
Pulp chamber of all teeth types has roof or walls. The pulp chamber roof contains one or more pulp horn which is an extension of pulp located directly under the cusp (in molars, premolars, canines) or developmental lobe (in incisors). In anterior teeth and premolars with one root canal the walls of pulp chamber gradually merge into the root canal and the division becomes indistinct. In multiple-rooted teeth (molars, twoand three-rooted premolars) the pulp chamber walls, floor and root canal orifices are well-defined.
The pulp chamber floor is formed by dentin of bifurcation (in two-rooted teeth) and trifurcation (in three-rooted teeth) of roots. Canal orifices are openings in the floor of the pulp chamber leading to the root canals, they are not a separate structure but are continuous with the pulp chamber and root canals. On the pulp chamber floor we can see dark developmental lines/grooves which connect root canal orifices. These lines sometimes are called pulpal floor map or dentin map because they can help to find root canal orifices. In most cases the orifices are located at the end of lines (fig. 26.1).
COMPLEX ANATOMY OF ROOT CANAL SYSTEM
A thorough knowledge of the root canal anatomy and its variations is required to achieve success in root canal therapy, along with diagnosis, treatment planning and clinical expertise. Root canal is considered to be round in cross-section with smooth walls. Such a canal can be seen in different drawings and pictures of preparation and obturation techniques. But the clinician should