Influence of Curing Time and Color Shade on Diametral Tensile Strength of Bulk Fill Composite Resins

摘要

This study was conducted to evaluate the influence of curing time and color shade of bulk fill composite resins on their diametral tensile strength (DTS). Two commercially available bulk fill composite resins, Beautifil Bulk Restorative? (Shofu, Japan; shade A and Universal) and Tetric N-Ceram? bulk-fill (Ivoclar-Vivadent, Liechtenstein; shade IVA and IVW) were investigated. The disc-shaped specimens (3 mm of thickness; 6 mm of diameter) were divided into 3 subgroups for each shade according to curing time (10 s, 15 s, and 20 s). All specimens were polymerized using LED curing unit (Bluephase Style, 1200 mW/cm2) and tested using Universal Testing Machine (Shimadzu, Japan) to determine the DTS. Data were statistically analyzed using Two Way ANOVA and Post Hoc Tukey HSD tests. The results showed that bulk fill composite resins with brighter color shades were statistically significant different (P<0,05) than darker shades in DTS. There was an increase in DTS with increased curing time and was statistically different (P<0,05). However, there was no statistically different interaction between curing time, and color shade. It can be concluded that color shade and increased curing time influence the diametral tensile strength of bulk fill composite resins.