J Korean Acad Conserv Dent.  2007 Jan;32(1):19-27. 10.5395/JKACD.2007.32.1.019.

Proposal of new dental color-space for aesthetic dental materials

• Oh YJ
• Park SJ
• Kim DJ
• Cho HG
• Hwang YC
• Oh WM
• Hwang IN

• KMID: 1986927
• DOI: http://doi.org/10.5395/JKACD.2007.32.1.019

Abstract

The purpose of this study is to develope new dental color-space system. Twelve kinds of dental composites and one kind of dental porcelain were used in this study. Disk samples (15 mm in diameter, 4 mm in thickness) of used materials were made and sample's CIE L*a*b* value was measured by Spectrocolorimeter (MiniScan XE plus, Model 4000S, diffuse/8degrees viewing mode, 14.3 mm Port diameters, Hunter Lab. USA). The range of measured color distribution was analyzed. All the data were applied in the form of T### which is expression unit in CNU Cons Dental Color Chart. The value of L* lies between 80.40 and 52.70. The value of a* are between 10.60 and 3.60 and b* are between 28.40 and 2.21. The average value of L* is 67.40, and median value is 67.30. The value of a* are 2.89 and 2.91 respectively. And for the b*, 14.30 and 13.90 were obtained. The data were converted to T### that is the unit count system in CNU-Cons Dental Color Chart. The value of L* is converted in the first digit of the numbering system. Each unit is 2.0 measured values. The second digit is the value of a* and is converted new number by 1.0 measured value. For the third digit b* is replaced and it is 2.0 measured unit apart. T555 was set to the value of L* ranging from 66.0 to 68.0, value of a* ranging from 3 to 4 and b* value ranging from 14 to 16.

Keyword

Tooth color; Color system; Dental color space; CIE L*a*b*; Esthetic material; Dental color chart

MeSH Terms

Dental Materials*
Dental Porcelain
Dental Materials
Dental Porcelain

Figure

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  Figure 1 Schematic diagram of the CIE L*a*b* color system.

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  Figure 2 Diagram of the CNU-Cons Dental Color system.

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  Figure 3 L* and C* value of the tested materials.

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  Figure 4 a* and b* value of the tested materials.

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  Figure 5 Histogram of the L* value.

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  Figure 6 Histogram of the a* value.

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  Figure 7 Histogram of the b* value.

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