J Korean Acad Conserv Dent.  2011 Mar;36(2):108-113. 10.5395/JKACD.2011.36.2.108.

Effect of the difference in spectral outputs of the single and dual-peak LEDs on the microhardness and the color stability of resin composites

• Park HJ
• Son SA
• Hur B
• Kim HC
• Kwon YH
• Park JK

• KMID: 2251814
• DOI: http://doi.org/10.5395/JKACD.2011.36.2.108

Abstract

OBJECTIVES
To determine the effect of the spectral output of single and dual-peak light emitting diode (LED) curing lights on the microhardness and color stability of commercial resin composites formulated with camphorquinone and alternative photoinitiators in combination.
MATERIALS AND METHODS
Three light-polymerized resin composites (Z100 (3M ESPE), Tetric Ceram (Ivoclar Vivadent) and Aelite LS Posterior (Bisco)) with different photoinitiator systems were used. The resin composites were packed into a Teflon mold (8 mm diameter and 2 mm thickness) on a cover glass. After packing the composites, they were light cured with single-peak and dual-peak LEDs. The Knoop microhardness (KHN) and color difference (DeltaE) for 30 days were measured. The data was analyzed statistically using a student's t-test (p < 0.05).
RESULTS
All resin composites showed improved microhardness when a third-generation dual-peak LED light was used. The color stability was also higher for all resin composites with dual-peak LEDs. However, there was a significant difference only for Aelite LS Posterior.
CONCLUSIONS
The dual-peak LEDs have a beneficial effect on the microhardness and color stability of resin composites formulated with a combination of camphorquinone and alternative photoinitiators.

Keyword

Alternative photoinitiators; Camphorquinone; Color stability; Dual-peak light emitting diode (LED); Microhardness; Spectral outputs

MeSH Terms

Camphor
Composite Resins
Enzyme Multiplied Immunoassay Technique
Fungi
Glass
Light
Polytetrafluoroethylene
Camphor
Composite Resins
Polytetrafluoroethylene

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