Abstract
The purpose of this study was the objective chromatical measuring of the primary teeth color of the Japanese children and the investigation of the effectiveness of the Color Difference Meter used in this study.
The normal primary anterior tooth colors of 30 Japanese children ranging from 2 years 4 months to 6 years 5 months of age (avarage: 4 years 3 months)were chromatically measured using the Light Guided Color Difference Meter CD-270 (Murakami Color Research Labo). The data was compared with that of the chromatical measuring of 18 Japanese children aged from 3 years 3 months to 6 years 6 months (avarage: 5 years) using the Color and Color Difference Meter 1001 DP (Nippon Denshoku Co. ) which were reported on previously.
The following results were obtained.
1) Precise chromatical measuring of the primary tooth colors in the oral cavity is available using the Light Guided Color Difference Meter CD-270 which has the filters for intercepting the influence of the light from the outside of the light guide head, and is also able to measure the chromaticity in instantaneously.
2) The mean chromatical values of XYZ, and L measured with the CD-270were higher than those measured with the 1001 DP.
3) The mean chromatical values of a b of all kinds of primary anterior teeth measured with the CD-270 were plus values and showed a reddish-yellowish color, while the values measured with 1001 DP were almost zero and showed an extremely white color and there was little difference among the kinds of primary anterior teeth.
4) Since the diameter of the light guide head is 7 mm, it is too big for chromatical measuring of primary anterior teeth, the data of L a b was in danger of being influenced by the gingival color in the cases of the CD-270. In the cases of the 1001 DP, the data of L a b was in danger of showing only enamel surface color or only the value of L. There remains the question of not being able to detect the particular primary tooth color.
5) The diameter of the light guid head of CD-270 should be made into a smaller size.
