The effect of bulk-fill composites: Activa and Smart Dentin Replacement on cuspal deflection in endodontically treated teeth with different access cavity designs.

Aim: The aim was to evaluate the effect of bulk-fill composites - Activa and Smart Dentin Replacement (SDR) on cuspal deflection in endodontically treated teeth with different access cavity designs.

Materials And Methods: Forty-two maxillary first premolar teeth were randomly divided into three experimental groups based on different access designs as Group I - conservative endodontic cavities (CECs), Group II - traditional endodontic cavities, and Group III - CECs with diverging walls and two subgroups, based on the different access cavity restorations subgroup A-Activa and subgroup B-SDR with = 7 per group. Root canal treatment was completed under the dental operating microscope.