Comparison of bulk-filling materials: depth of cure and fracture toughness
Objectives: ,New bulk filling materials has been launched lately, however materials have quite large variations in means of materials properties eg. Sonic fill includes vibration assisted polymerization composite whereas Xenius Base is short fiber reinforced composite.
The aim of our study was to characterize fracture toughness and depth of cure 7 new common bulk fill resin composites (BFC).
Methods: Fracture toughness specimens were prepared by using a metal mould, with dimensioned of 2mm x 5mm x 25mm. Composite was applied into to the mould layer by layer. A razor blade was carefully set on at half way of specimen. The specimen was light cured 3 x 40s from one side, then turned around and the curing was repeated. Fracture toughness was measured using 3-point bending test using span of 20 mm.
The depth of cure were performed using 10mm high cylinder with 4 mm diameter (ISO 4049). Cylinder were filled with composite and light polymerized for 20s (3M Espe Elipar™ S10). Cured bulk composite was removed from cylinder and then uncured composite was removed by plastic spatula. The remaining part, the cured part was measured with the digital sliding gauge.
Results were evaluated using one-way ANOVA followed with Tukey's post hoc test (α = 0.05).
Results:
Groups | Kic | Depth of Cure (mm) |
Voco Xtra base (Voco) | 2,0 (0,3) | 4,9 (0,3) |
Venus Bulk Fill (Heraus Kulzer) | 2,2 (0,3) | 4,2 (0,1) |
Tetric Bulk Fill (Ivoklaer) | 2,2 (0,3) | 3,2 (0,1) |
Alert (Pentron) | 2,9 (0,5) | 2,5 (0,1) |
SDR (Dentsply) | 2,9 (0,5) | 4,4 (0,2) |
Sonic Fill (Kerr) | 3,0 (0,3) | 3,2 (0,1) |
Xenius Base (StickTech) | 4,6 (0,7) | 4,6 (0,5) |
ANOVA revealed significant differences between materials both in fracture toughness and depth of cure (p<0.05).
Conclusions: Bulk filling composite has large differences in fracture toughness values. Xenius Base has clearly highest fracture toughness properties among tested materials.