Prepared by:

Dr. Michael Solomonov, DDS

•The openings always ended short of the apices

by 0.20-3.80mm. Gutierrez and Ayuayo

1995.

APICAL CONSTRICTION

• Anatomical landmark

• The narrowest apical diameter of the root canal

• Not the same as CDJ

• Debate about ideal working length

Cemento-Dentin Junction

• Histology landmark

• Interface of dentin and cementum

• Near foramen

• Not apical constriction

No exact distance from the radiographic apex can be given, because the distance from the radiographic apex to the apical constriction varies widely from tooth to tooth.

Langeland.

Deviation of the root canal from the long axes of the root is recognizable on the radiograph only when the foramen ends on the mesial or distal aspect of the root.

When the foramen ends on the buccal or lingual aspect it is not possible to recognize it radiographically.

Gutierrez and Aguayo 1995.