Restor Dent Endod.  2012 Aug;37(3):130-135. 10.5395/rde.2012.37.3.130.

Power density of various light curing units through resin inlays with modified layer thickness

• Hong SO
• Oh Y
• Min JB
• Kim JW
• Lee BN
• Hwang YC
• Hwang IN
• Oh WM
• Chang HS

• KMID: 1995651
• DOI: http://doi.org/10.5395/rde.2012.37.3.130

Abstract

OBJECTIVES
The purpose of this study was to enhance curing light penetration through resin inlays by modifying the thicknesses of the dentin, enamel, and translucent layers.
MATERIALS AND METHODS
To investigate the layer dominantly affecting the power density of light curing units, resin wafers of each layer with 0.5 mm thickness were prepared and power density through resin wafers was measured with a dental radiometer (Cure Rite, Kerr). The dentin layer, which had the dominant effect on power density reduction, was decreased in thickness from 0.5 to 0.1 mm while thickness of the enamel layer was kept unchanged at 0.5 mm and thickness of the translucent layer was increased from 0.5 to 0.9 mm and vice versa, in order to maintain the total thickness of 1.5 mm of the resin inlay. Power density of various light curing units through resin inlays was measured.
RESULTS
Power density measured through 0.5 mm resin wafers decreased more significantly with the dentin layer than with the enamel and translucent layers (p < 0.05). Power density through 1.5 mm resin inlays increased when the dentin layer thickness was reduced and the enamel or translucent layer thickness was increased. The highest power density was recorded with dentin layer thickness of 0.1 mm and increased translucent layer thickness in all light curing units.
CONCLUSIONS
To enhance the power density through resin inlays, reducing the dentin layer thickness and increasing the translucent layer thickness would be recommendable when fabricating resin inlays.

Keyword

Dental radiometer; Layer thickness; Power density; Resin inlay

MeSH Terms

Dental Enamel
Dentin
Inlays
Light

Figure

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  Figure 1 Photograph of the custom-made aluminum mold with a movable Teflon plate attached to a bolt.

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  Figure 2 Power densities of light curing units measured through 0.5 mm resin wafers. The power densities through the dentin, enamel, and translucent shades showed statistically significant differences (n = 7, p < 0.001). D2, dentin shade A2; E2, enamel shade E2; T1, translucent shade T1; 360, Optilux 360; FL2, Elipar FreeLight 2; S10, Elipar S10.

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