In vitro analysis of flowable and high viscosity bulk fill composite versus conventional composite in core build up...

This study aimed to test the load to fracture of flowable and high viscosity bulk-fill composites compared to a convetional (packable) composite used to build up pulpless teeth. 45 endodontically treated premolars were restored with fiber posts then divided into three groups (N = 15) according to the core build-up material. SDR group: (Smart Dentine Replacement), (BF): Filtek One Bulk Fill and (CC) Filtek Z350 packable composite. After core build up the teeth received full coverage crowns. Load to fracture (Newton) was recorded for each specimen. One-way ANOVA and Tukey multiple comparisons test were used. The highest load at fracture was shown by (CC) group (1067 N), followed by (BF) group (879 N), and the SDR group (838 N). One way ANOVA and Tukey's multiple comparisons test demonstrated no significant differences between CC, SDR, and BF groups (p > 0.05). The three materials showed comparable load to fracture. Further studies with simulation to occlusal forces and oral temperature are required.