Depth of cure evaluation of four different light-activated composites using different curing modes

الملخص EN

Background : as light passes through the bulk of the composite material, the light intensity is greatly reduced due to light absorption and scattering by resin composites, thus, decreasing the effectiveness of cure through the depth of the composite layer.

This study investigated the influence of different new curing modes (conventional and experimental) and composite formulations on depth of cure using the ISO scraping test.

Materials and methods : this study investigated the depth of cure (ISO scraping method) of four conventional composites after exposure to different curing modes.

A two-piece aluminum mold with a diameter of 4mm and a height of 8mm was used as a mold for the composite specimens.

VIP light curing unit was used to deliver all the curing modes for photo-curing of all the composite specimens in this study.

Parameters included six curing modes : Control (C), Pulse Delay I (PDI), Pulse Delay II (PDII), Soft-start (SS), Pulse Cure I (PCI), and Pulse Cure II (PCII) plus three experimental curing modes of higher energy density : Prolonged low-intensity pulse cure mode (PLPC), Prolonged moderate-intensity pulse cure mode (PMPC) and Rapid high-intensity continues cure mode (RHCC) for each of the four different light-activated composite materials (Tetric Ceram, Heliomolar, Herculite XRV and Degufill Mineral).

The height of the cylinder of cured material was measured with a micrometer to an accuracy of 0.01 mm.

This value was divided by two (in compliance with ISO CD4049: 2000), and recorded as the depth of cure in mm for that specific specimen.

Results : statistical analysis of the data by using the one-way analysis of variance revealed that, there is statistically very highly significant difference for all the depth of cures between the curing modes and composite types.

Conclusion : this study indicated that, although, both curing mode and composite type significantly affect depth of cure but the effect of composite composition on the depth of cure is more predominant than that of curing mode.