Access through the crown
Advantages :
-Allow for better isolation with the rubber dam
-Better esthetic anf functioning.
-Good coronal seal between visits
Limitations :
-Procedures more difficult with the crown in place
-Increased chance for an iatrogenic mishap due to restricted visibility
-Difficult to removal of canal obstructions (post)
-Difficult to locate hidden caries , fracture
-Difficult to locate missing canal