Depth of cure, flexural properties and volumetric shrinkage of low and high viscosity bulk-fill giomers and resin composites

Abstract

The purpose of this study was to investigate the depth of cure, flexural properties and volumetric shrinkage of low and high viscosity bulk-fill giomers and resin composites. Depth of cure and flexural properties were determined according to ISO 4049, and volumetric shrinkage was measured using a dilatometer. The depths of cure of giomers were significantly lower than those of resin composites, regardless of photo polymerization times. No difference in flexural strength and modulus was found among either high or low viscosity bulk fill materials. Volumetric shrinkage of low and high viscosity bulk-fill resin composites was significantly less than low and high viscosity giomers. Depth of cure of both low and high viscosity bulk-fill materials is time dependent. Flexural strength and modulus of high viscosity or low viscosity bulk-fill giomer or resin composite materials are not different for their respective category. Resin composites exhibited less polymerization shrinkage than giomers.

Linear polymerization shrinkage of Bulk Fill resins

“…Thus, as mentioned above, by increasing the filler content and, therefore, decreasing the flowability, the modulus of elasticity increases in the same proportion and the amount of organic matrix present in the composite is decreased 17 . This fact assists in a reduction in the polymerization contraction 18 . An increase in the modulus of elasticity of a material can be obtained through a greater incorporation of filler particles, which reduces the amount of organic matrix in the composite and favours a reduction in the polymerization shrinkage [18][19][20] .…”

“…This fact assists in a reduction in the polymerization contraction 18 . An increase in the modulus of elasticity of a material can be obtained through a greater incorporation of filler particles, which reduces the amount of organic matrix in the composite and favours a reduction in the polymerization shrinkage [18][19][20] . Considering the differences in the composition of the organic matrices of Bulk Fill resins, it is also possible that the contraction gap is related to the presence of the TEGDMA monomer in some formulations, as well as the interactions with other diluent monomers.…”

Effect of tooth brushing on gloss retention and surface roughness of five bulk‐fill resin composites

“…Bulk‐fill RBC contains different types of filler and have different filler loading (Table ). While physical properties, such as the polymerization shrinkage and the depth of cure of bulk‐fill RBCs, have been extensively studied, the effect of tooth brushing these bulk‐fill RBCs has yet to be studied. Whitening dentifrices have become popular with both manufacturers and patients alike.…”

“…22,24,25,27,28 Bulk-fill RBC contains different types of filler and have different filler loading (Table 1). While physical properties, such as the polymerization shrinkage and the depth of cure of bulk-fill RBCs, have been extensively studied, [29][30][31][32][33] the effect of tooth brushing these bulk-fill…”

Características mecânicas e ópticas de resinas bulk-fill: revisão de literatura

“…As resinas bulk-fill utilizadas no estudo de Tsujimoto et al 16 (2017) continham um modulador de polimerização de alto peso molecular para reduzir a contração volumétrica 15 . Essa única estrutura molecular contribui para o atraso do ponto gel, o que representa um aumento da viscosidade por meio da formação de cadeia, podendo permitir mais tempo para compensar o encolhimento e, então, reduzir a contração volumétrica 5 .…”