Effect of remaining coronal structure on the resistance to fracture of crowned endodontically treated maxillary first premolars.

Objective: Endodontically treated maxillary first premolars present a restorative challenge. The objective of the present study was to assess the resistance to fracture of crowned endodontically treated maxillary first premolars under simulated occlusal load, while preserving various degrees of remaining coronal structure.

Methods And Materials: The study consisted of 50 intact maxillary first premolars with bifurcated roots and similar root diameter and length, randomly divided into 5 equal experimental groups.