Effectiveness of four different light-activated composites cure with different curing modes

Abstract

ABSTRACT
Background: This study investigated the influence of different new curing modes on the effectiveness of cure of
different light- activated composites to examine their efficacy in satisfying composite adequate polymerization.
Materials and methods: This study investigated the hardness of the top/bottom surfaces and hardness ratio of two
mm thick composite specimens after exposure to different curing modes. 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).
Results: Results reveled that, there was statistically very highly significant difference for all the hardness ratios with the
curing modes except the hardness ratio of Heliomolar composite where, there was an insignificant difference
because, the mean hardness ratio of Heliomolar composite with the first six curing modes (control, PDI, PDII, SS, PCI,
PCII) was not calculated because, the poor polymerization of Heliomolar bottom surfaces with these six curing
modes.
Conclusion: This study indicated that, clinical usage of Control, PDI, PDII, SS, PCI and PCII curing-modes is not
advocated to cure Heliomolar and Degufill Mineral composites while the experimental curing modes (PLPL, PMPC
and RHCC) satisfied effectiveness of composite cure for all the composites being tested.
Key words: Resin composite, light curing modes, microhardness, photo-activation and composite cure. J Bagh Coll
Dentistry 2009; 21(2):39-43)