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.
Subject(s)
Dental Materials , Dental PorcelainABSTRACT
Of the four basic medical diagnoses in Chinese medicine, tongue examinations rank in importance with pulse examinations. The conventional method of clinically recording the color of the tongue by taking photographs with film cameras generally presents various problems, such as the difficulty of establishing objective procedures and the long-term storage of records.<br>The authors accordingly attempted to enhance the objectivity of tongue examinations by devising a new image correction procedure combining the use of color-and-size-matching stickers (image correction color charts) and computers utilizing a digital camera. As a result, the images that are output after correction not only reproduce the tongue in its actual size but also make it possible to approximate color system values measured from the actual tongue, thereby suggesting the possibility of a useful procedure for making objective evaluations in tongue examinations.
ABSTRACT
Objective: To measure and compare the color of a new and a conventional Vita shade guide(VITAPAN 3D-Master and LUMIN RVACUUM-Farbskala) in order to provide the references for clinical application.Methods: Color in the two shade guides was measured with Minolta colorimeter CR-321 under the light of D 65 and reported in CIE1976L*a*b* color system. Each tab was detected 3 times in the same dimensions at the middle facial surface. Mean values were calculated as the shade of the tab.Results: The range of color value in VITAPAN 3D-Master was larger than that in LUMIN R VACUUM-Farbaskala because the lower value tab was added. The distrbution of a* deviated to the red color , while the green color was relatively deficient. The yellow color could cover the color space of Chinese teeth, and the blue was not enough, although the distribution of b* was enlarged. The tabs of the two shade guides did not match with each other. Only a few tabs could not tell in shade by naked eyes. Conclusion: VITAPAN 3D -Master shade guide can not cover the color of Chinese teeth although it has 10 tabs added and color space enlarged.
ABSTRACT
Objective; To study the chromatic distribution of the chromatic value of Vitapan 3D- Master shade guide in color space. Methods: The color space of.Vitapan 3D-Master shade guide was measured and analyzed with CIE-1976-L* a* b. system and MINOLTA chromatic instrument (CR-321 ) under D65 standard source. Results: 26 shades of Vitapan 3D-Master could be divided into 5 groups according to the 3-dimensional layers. Inside the 2nd, 3th and 4th group, 6 shades distributed as equidistant ring circling M2 shade because their hue and chroma were different. The hue of L1. 5 and L2. 5 deflected to yellow, R1.5 and R2. 5 to red,that of M1-3 was intervenient. Conclusion: Vitapan 3D-Master shade guide is equidistant in color space and can be used more effeciently than Vitapan classical. Its chromatic value distribution perfectly and evenly covered color region of nature tooth.