Evaluation Of Accuracy Of Computer Colorimeter In Shade Maching

ObjectiveCompare the exactive of ShadeEye-NCC and visual sensation in shade selection,to evaluate the reliability and reasonability of tooth color matching by using ShadeEye-NCC。Methods27 patient of haif upper central incisor dental defect,need ceramic reparation,match the tooth color of the healthy central incisor by using ShadeEye-NCC and visual sensation。By the same technician in accordance with the color results separately roast Production of PFM,patients were wearing PFM into two groups(non cement),record their central incisor by a Canon EOS D60 digital camera in studio environment。Photographs were taken under a set exposure parameters,the color values were obtained from the digital images using Camera RAW for Adobe Photoshop 8.0 and quantified according to an internationally recognized scale as CIELAB color values。Calculate the aberration of the natral tooth and PFM making in different methods,compare△E~*,△L~*,△a~*,and△b~*in pair T-test using SPSS13.0 software package,analysis the difference of the two methods from hue,chroma and luminosity.Firing satisfaction of color forms randomly,statistics the satisfaction of the color of PFM,compare satisfaction of color in pair T-test using SPSS13.0 software in pair T-test using SAS 13.0 software。 Result1.Compared to the△E~* of the visual colorimetry,the△E~* of the natural teeth and the average instrumental chromatic aberration of porcelain crown made of two kinds of colorimetry are a little smaller,but the differences between them have no statistics significance(P＞0.05)。2.Among the three colorimetry parameters,the values of△L~* and△a~* have statistics significance(P＜0.05),while△b~* has no statistics significance (P＞0.05)。3.The lightness difference△L~* of these two colorimetries have statistics significance(P＜0.05),while the chroma difference△C~*and△H~* does not have。4.The color satisfaction between the porcelain crown of these two groups has no statistics significance(P＞0.05)。Conclusion1.ShadeEye NCC is better than the visual colorimetry in the selection of luminosity。2.ShadeEye NCC is better than the visual colorimetry in the selection of red-green。3.satisfaction will get if ShadeEye NCC can be applied in clinical and it is a good methord in the study of color。4.Because the high sensitivity in the instrument operation,deviation may come out,so we should repeat the operation。Therefore,this instrument awaits improvements in the operating stability,to be a really advanced tool in shade maching。...