Coronal Disassembly
-If the existing restoration functionally designed well fitting and esthetically pleasing ,
-The access the pulp chamber during retreatment is better approach through the existing restoration
Indicated :
-No complicate radicular restoration
-Easily to locate the canal orifices
-Easily line access to the apex
- if the existing restoration good do drilling via crown
- if the radicular restoration is easy removed and there is no post, no ledge or fracture instrument ---> straight forward to remove restoration