216例金瓷修复体与VITA成品比色板的颜色分析

目的:比较分析临床上金属烤瓷冠修复体与医生所选比色板色样间的颜色差异。方法:随机选取216例已完成的镍铬金属烤瓷冠,应用Shade-Eye NCC电脑比色仪测定该烤瓷冠及其对应的Vita比色板色样的色彩值与色度值,测量结果用孟塞尔(Munsell AM)颜色三属性(即色相、明度、饱和度)表色系统及CIE1976 L*a*b*表色系统表示。结果:烤瓷冠平均明度比所对应色样偏亮,平均红绿色品比对应色样偏红,平均黄兰色品比对应色样偏黄。烤瓷冠与所选色样间的色差平均为6.177,属于可识别范围。烤瓷冠平均彩度比对应色样偏浓,平均明度比对应色样偏亮,平均色相比对应色样偏红。结论:技工加工完成的烤瓷冠颜色与医生所选比色板色样间存在着显著性差异     

分光光度比色仪对牙齿漂白效果的分析

目的 采用分光光度比色仪分析牙齿漂白后不同部位颜色CIE L*、a*、b*值的变化。方法 选择67个健康完整的上颌中切牙,颜色大于A3（Vita经典比色板）。分光光度比色仪比色,记录颈部、体部、切端牙色。进行诊室漂白治疗（35%H2O2协同冷光漂白仪）后再次记录各部位牙色,计算ΔE、ΔL*、Δa*、Δb*和治疗有效率。对数据进行方差分析、配对t检验和Pearson相关分析。结果 治疗有效率分别为：颈部86.6%,体部86.6%,切端85.1%。ΔE均值：颈部5.09,体部4.44,切端4.40。漂白后L*值升高,a*和b*值降低,均有统计学差异（P<0.01）。颈部和体部基线b*值与ΔE成正相关。结论 35%H2O2协同冷光漂白仪照射有较好的牙齿漂白效果,顺序为颈部>体部>切端。颈部黄色降低幅度最大,切端明度增加最多。基线b*值越高,色差越大。     

椅旁操作次数对恒温漂白活体上中切牙疗效的影响

目的 本实验旨在研究不同椅旁操作次数对活体上中切牙恒温漂白疗效的影响。 方法 受试者接受连续3次（每次间隔1 d）、每次45 min的恒温漂白治疗,以比色仪测量每次漂白前后上中切牙的L*、a*、b*颜色参数值,分析变化,并记录比色板比色结果。所得数据以配对t检验进行统计分析。 结果 统计分析显示,所有受试者接受漂白后牙体的L*、W(Lab)增大,b*降低,即牙齿的亮度和白度值增加,颜色向蓝色转变,且随漂白次数增多幅度变大,差别有统计学差异（P<0.05）。每次漂白操作后牙体颜色变化的色差均大于1.7个NBS单位,说明每次漂白后的颜色变化均能被肉眼辨别。 结论 增加漂白次数能提高漂白疗效。     

两种常用比色板的临床色度学研究

目的从临床角度探讨两种比色板色度学的变化。方法用Shade Eye EX电脑比色仪分别测试Shofu16色比色板和Vita16色比色板的比色片，获得比色片的色调、彩度、明度、色相和瓷粉配方。结果两组比色片的B色调全测为A系列，大多数比色片的色相测为R系列；多数Vita比色片的彩度高于Shofu比色片；两组比色片的明度排列次序不符合Vita 16色比色板的明度排列次序指示，Shofu比色片的明度普遍高于Vita比色片；绝大多数比色片的颜色复制需用偏红色调瓷粉，或需添加偏红色调及红色瓷粉。结论用Shofu 16色比色板或Vita 16色比色板比值和配色，需添加其他系列或特殊颜色的瓷粉。     

数码摄影应用于牙科比色可行性的研究

目的:对数码相机应用于牙科测色进行实验探讨,与专业测色仪器比较分析其合理性与可行性.方法:使用数码相机在D65光源的d/0°观测方式下,拍摄3D-Master比色板,其测色结果与CRAIC QDI2000显微光谱分析仪、ShadeEye-NCC电脑比色仪的色度数据进行比较.结果:在比色板色片的明度、饱和度参数的排序上,3种仪器的测试结果表现基本一致;数码相机测定的比色片色度参数(L*a*b*/C*H°)与电脑比色仪的结果间没有统计学差异,和显微光谱分析仪的结果在明度参数L*上存在统计学差异,根据相关性检验的结果,3种仪器测得明度参数间存在非常显著的正相关(P＜0.0001).结论:在一定实验条件下,数码相机用于牙体色彩测试结果的稳定性与专业测色仪器基本一致,并在操作方面更有优势.     

色彩学知识与牙科比色Ⅲ.比色方法及颜色信息传递

本次系列讲座的前两讲已经分别介绍了色彩学的基本知识以及影响比色的因素,本次讲座将重点介绍视觉比色的方法,并探讨仪器测色及颜色信息传递等问题. 一、视觉比色的基本方法 人眼对明度差异的敏感度明显高于同等程度的色相差异或饱和度差异,因此修复体与天然牙明度的一致性是修复体制作过程中最重要的问题.进一步而言,比色过程中要重点考虑明度确定的准确性,因此,比色时应首先在柔和的光线下,对天然牙进行明度的判断,然后再在较高的照度下进行饱和度与色相的选择.合理的比色顺序有利于降低比色的难度.     

两种VITA比色板的色度学比较

目的：对两种VITA比色板的色度范围进行比较分析，并与中国人牙色度范围相比较，以便为临床选色和瓷粉的使用提供指导。方法：选用CIEl976—L^*a^*b^*色度系统，用Minolta CM—2600d分光测色计对两种VITA比色板的色度佰进行测定，对二者的色度范围做了比较分析。结果：与Vita C1assical比色板相比，Vita 3D Master比色片明度值在较低的区域也有分布，a^*增大，使颜色向黄红色调方向移动；b^*也增大，使颜色的饱和度增大。Vita 3D—Master比色板几乎全部涵盖了Vita Classical比色板的明度和饱和度范围。二者与中国人牙色度范围相比较，部缺乏明度较高的色片，Vita 3D Master比色板较Vita C1assical比色板能够更好的覆盖中国人牙色范围，二者的色度范围相加则更有代表性。结论：Vita 3D—Master比色板较Vita Classical比色板颜色分布的范围更符合中国人牙色度范围、排列更合理，为临床准确地选色、配色提供了可靠的依据。     

浸泡着色氧化锆陶瓷及其比色板的色度学研究

目的:测定浸泡着色的Vita In-Ceram YZ氧化锆陶瓷试样和染色液比色板的色度值。方法:制备5组陶瓷试样,分别用LL1至LL5染色液浸泡着色2min,1530℃烧结2h,磨床单面磨至1.5mm厚度,黑色背景下用分光光度计对陶瓷试样和染色液比色板进行颜色测定。计算试样和比色板之间的色差以及计量心理量的明度差、色相角差、彩度差。结果:染色后试样的色度值范围为L:59.81-78.93;a:0.36-9.36;b:19.62-26.91。试样与染色液比色板的色空间相近,色差值4.02-6.96个NBS单位。两者之间差异最大的是色相角差,均值7.38;其次是彩度差,均值2.31;最小为明度差,均值2.29。结论:染色液比色板与浸泡着色氧化锆陶瓷之间具有良好的颜色适合性。对氧化锆基底瓷的颜色调控应同时包括明度、彩度和色相角。     

3种不同金瓷修复体颜色差异的研究

目的比较3种不同金瓷修复体之间及与Vitapan classical比色板的色彩差异。方法应用CIE1976L*a*b*颜色系统,采用高像素数码摄影及计算机处理技术,在标准光源及相同条件下,采集了24件3种金瓷修复体与A2比色片的样本图片,测量、分析其色度值。结果从颈部到切端,3种金瓷修复体与A2比色片明度值均呈递增趋势,彩度值呈递减趋势;金瓷修复体明度值均高于A2比色片的明度值;色相为黄红色;彩度值不同,修复体较A2比色片偏黄红色;金沉积金瓷修复体明度及彩度高于其他两种。结论3种不同金瓷修复体颈部、体部与VITA比色板存在颜色差异,金沉积烤瓷冠、金合金烤瓷冠在色泽上优于镍铬合金烤瓷冠。     

目测法比色准确性的评估

目的:研究目测法比色的准确性.方法:采用Vitapan比色板对100颗上颌天然切牙进行比色,选定比色片标号.在CIE1976L*a*b*色度系统下,运用松风ShadeEye NCC电脑比色仪对天然牙和比色片进行颜色的测量和分析.结果:目测法比色所选色片与天然牙的色差为0.26～6.70,平均色差为1.78.比色片的明度值与天然牙的明度值有显著性的差异.结论:门诊医师所选比色片与天然牙间的颜色存在一定的差异.     

冷光美白治疗氟斑牙的初步探讨

目的：观察Beyond牙齿冷光美白治疗氟斑牙的效果。方法：选取10名受试者,用Beyond牙齿冷光美白进行漂白治疗。术前和术后分别采用数码照像计算机色度分析系统对上颌中切牙进行比色,术后1年复查受试者牙齿的色度变化。结果：术前受试者上颌中切牙的平均L＊,a＊,b＊值为73.89±2.80,7.77±1.05和21.50±1.21,经过Beyond牙齿冷光美白三次治疗后上颌中切牙的平均L＊,a＊,b＊值为82.95±2.42,3.39±0.91和12.97±1.36,平均色差ΔE＊ab为13.18±1.53。术后1年复查受试者上颌中切牙的平均L＊,a＊,b＊值为81.50±2.10,3.69±0.76和13.66±1.32,平均色差ΔE＊ab为11.45±1.64。结论：Beyond牙齿冷光美白对氟斑牙具有较好的漂白效果,并能较长时间维持漂白效果。     

Influence of illuminants on the color distribution of shade guides

STATEMENT OF PROBLEM: Although a shade tab in a shade guide is matched to a natural tooth in the order of value, hue, and chroma, there are limited data on the color distribution of currently available shade guides sorted by these 3 parameters. Furthermore, spectrophotometric color measurements of shade tabs differ depending on the standard illuminant employed. PURPOSE: The purpose of this study was to determine the color distributions of 2 shade guides in value (CIE L( *)), chroma (C( *)(ab)) and hue angle (h(o)) scale relative to the standard illuminants D(65), A, and F2. MATERIAL AND METHODS: Color of shade tabs (n=36) from 2 shade guides (Vita Lumin and Chromascop) were measured, and the distributions for CIE L( *), C( *)(ab) and h(o) values were compared. Color differences of shade tabs depending on the illuminant were calculated. The distributions of the ratios of CIE L( *) and C( *)(ab) values of each shade tab compared with the lowest value tab or the lowest chroma tab were determined. The data for the value, chroma, and hue angle within each shade guide were analyzed with a 2-way ANOVA with the factors of shade designation and type of illuminant (alpha=.05). Color difference caused by change of illuminant was analyzed with a 2-way ANOVA with the factors of shade designation and pair of illuminants compared (alpha=.05). The Scheffe multiple comparison test was performed as a post hoc test. RESULTS: CIE L( *), C( *)(ab) and h(o) values were influenced by shade designation and type of illuminant in both shade guides. Color difference caused by change of the illuminant was influenced by the shade designation and pair of illuminants compared. The order of mean color differences of 16 Vita Lumin shade tabs by pairs of illuminants compared was as follows: DeltaE( *)(ab) (D(65)/F2) = 1.63 3.7). Color distribution of 2 shade guides by the value and chroma was not logical.     

测色仪分析Solidex树脂与比色板颜色的匹配性

目的：分析Solidex体层树脂与Vita比色板色标颜色的匹配性。方法：选用Solidex体层树脂A1、A3、C2色调,每一色调制备5个试样（2.0mm厚,10mm直径）,及Z100树脂A1、A3、C2色调树脂试样（4.0mm厚,10mm直径）作为背景试样。ShadeEyeNCC测色仪测量Solidex树脂试样及对应Vita比色板色标的L＊a＊b＊值。测量后,减小Solidex树脂试样的厚度分别至1.8mm、1.6mm、1.4mm、1.2mm、1.0mm,测量试样颜色并计算试样与比色板色标的色差值。结果：Solidex树脂试样与色标间的色差值范围6.18～14.29;并且随着试样厚度减小,色差值增大。结论：在本研究中Solidex树脂试样与比色板色标的色差值较大,并且为大多数观察者所不可接受。     

Defining a natural tooth color space based on a 3-dimensional shade system

STATEMENT OF PROBLEM: The natural tooth color space reported by a manufacturer may not represent the comprehensive spectrum of natural teeth for all population groups. PURPOSE: The purpose of this study was to define a natural tooth color space within the Greater Buffalo, New York population and to compare that to the color space determined by a manufacturer. MATERIAL AND METHODS: Nine hundred and thirty-three maxillary central incisors (501 patients) were measured with a shade-taking device (Vita Easyshade). For each tooth, L*, a*, b* values, chroma, hue, and the closest shade (Vita 3D-Master) were recorded. A linear regression analysis was performed to determine how well the manufacturer's values predict actual values for L*, a*, and b*. Color differences (DeltaE*) between the Buffalo population and the closest shade were also calculated. A 1-sample t test was used to determine whether the color differences seen in the sample were statistically different from the perceptibility threshold, DeltaE*=3.7 (alpha=.05). RESULTS: All 3 attributes of the Buffalo population displayed a broader range than those from the shade guide. However, the regression analysis revealed a significantly positive relationship between the L*, a*, and b* values of the 2 methods (P<.001). The 1-sample t test revealed a significant DeltaE* (mean DeltaE*=6.15) difference from the perceptibility threshold of DeltaE*=3.7 (P<.001). CONCLUSIONS: Color differences between the Buffalo population and the shade guide were frequently above published perceptibility thresholds, but within the range of acceptability. The Buffalo population tooth color space encompassed the manufacturer's color space.     

The repeatability of an intraoral dental colorimeter

STATEMENT OF PROBLEM: Characterizing and reproducing color remain one of the most challenging aspects of dentistry. A relatively new intraoral colorimeter measures the color of natural teeth and metal-ceramic restorations and prints out a color recipe for the Vintage Halo Porcelain System. The reliability of the colorimeter is unknown. PURPOSE: The purpose of this study was to evaluate the reliability of a contact dental colorimeter and to correlate the shade registered by the colorimeter with the shade selected by experienced clinicians. MATERIALS AND METHODS: In part I of the study, 2 examiners (A and B) took 2 colorimeter measurements from the maxillary right central incisors of 11 subjects. The examiners were blinded to their own data and those of other investigators. The readings were repeated 3 weeks later with the same protocol. The Cronbach alpha reliability coefficient was used to analyze the collected data. In part II of the study, 2 experienced clinicians (examiners D and E) selected a shade from the classic Vita Lumin Vacuum shade guide for the maxillary right central incisors of the same 11 subjects. The clinicians were blinded to each other's selections and the colorimeter readings. It should be noted that the manufacturer of the colorimeter uses the terms shade, value, and hue to represent chroma, value, and hue, respectively, as defined in the Glossary of Prosthodontic Terms (J Prosthet Dent 1999;81:39-110). RESULTS: The reliability analysis results for each of the combined trials for shade, value, and hue were all >.94. The interexaminer reliability alpha values were >.9 for shade and value and.64 to.74 for hue. The interexaminer alpha represented the value range of each of 4 measurements. The intraexaminer reliability alpha values for shade, value, and hue were.99,.95, and.96 for examiner A and.99,.93, and.97 for examiner B, respectively. In part II of the study, the colorimeter agreed with itself 82% of the time, whereas clinicians agreed with each other on the selected shade 73% of the time. Selections made by the colorimeter and the clinicians matched 55% to 64% of the time. CONCLUSIONS: Within the limitations of this study, the colorimeter reliably measured the color of natural teeth.     

饮料与染色瓷粉比色板色度的匹配性研究

目的通过孟塞尔表色系研究饮料与染色瓷粉比色板色度的匹配性,为技工制作陶瓷修复体时选择染色瓷粉模拟天然牙的着色提供参考依据。方法采用分光光谱仪测量Vita Akzent、Vita Interno、Shofu Vintage &Unibond和Noritake Super Porcelain EX- 3染色瓷粉比色板各比色片和15种饮料的孟塞尔色参数,比较其邻近色相、邻近明度和邻近彩度的差异,用双向无序行列表的Fisher确切概率法进行统计。结果15种饮料与4种染色瓷粉比色板邻近色相的频次差异有统计学意义（P<0.05）,而邻近明度和邻近彩度的频次差异没有统计学意义（P>0.05）。结论4种染色瓷粉模拟15种饮料的着色除色相外没有区别,通过适当的色相、明度和彩度调配,4种染色瓷粉能够与15种饮料的色度大致相匹配。     

Spectrophotometric and visual evaluation of vital tooth bleaching employing different carbamide peroxide concentrations.

OBJECTIVE: The aim of the present study was to assess the hypothesis that the efficiency of vital tooth bleaching depends on the concentration of carbamide peroxide agents. METHODS: The front teeth of 30 subjects were bleached at home with 10%, 17% or 0% (control) carbamide peroxide for 1 week in a double-blind study design. Tooth shades were determined in the LCH color space employing a visual shade matching system and a spectrophotometer. Differences in lightness (Deltal), chroma (Deltac) and hue (Deltah) were measured to assess the treatment process. After 2 weeks of no treatment, tooth shades were evaluated again to assess stability of the resultant shade. RESULTS: First-time changes of shade values could be observed after 3 days in the 17% group and after 7 days in the 10% group. After 1 week, in both the 17% group (Deltal: 2.80, Deltac: -3.33, Deltah: 0.60) and the 10% group (Deltal: 2.61, Deltac: -2.54, Deltah: 0.09), values for lightness and chroma were significantly different from the control (Deltal: 0.13, Deltac: 0.14, Deltah: 0.21, p<0.05) with no difference between the test groups (p>0.05). Two weeks after treatment, a rebound of shade values could be observed in the test groups (p<0.05). SIGNIFICANCE: The study indicates that higher concentration bleaching agents might whiten teeth faster with major changes in lightness and chroma. However, by bleaching daily for 1 week, similar effects can be achieved with both a high and a low concentration agent. After treatment, a regression of the resultant shade has to be expected.     

三种牙齿漂白方案的短期效果比较研究

目的:体外评价三种漂白方案对人牙齿漂白的短期效果.方法:36颗刚拔除的人牙,沿唇(颊)舌方向中央剖开去髓后,随机分成三组,联合漂白组(A):38%HP45min/d×1+15%CP 8h/d×4;诊室漂白组(O):38%HP45min/2×2,家庭漂白组(H):15%CP 8h/d×14.分别于漂白前,漂白后即刻(0天),4天、7天、14天、21天用Crystaleye分光光度计电脑比色仪拍摄牙齿唇(颊)面照片,分析测量牙齿体部靠近中线区的漂白前后△E值.结果:疗程结束时,3组漂白效果无统计学差异(P>0.05);3组在漂白结束后4天时与漂白结束△E有统计学差异,但H组在7天后△E无统计学差异,而A、O组2周、3周时仍有统计学差异.结论:三种漂白方案短期内都有颜色回复,但回复量和持续时间不同.     

Vitapan 3D—Master比色片的色空间位置测定

目的：获得Vitapan 3D-Master比色板各色片的色度值分布规律。方法 ：用美能达色差计CR321（D65光源）以CIE－1976－L^*ab^*色度值对市售Vitapan 3D-Master比色板进行色空间的测定和统计，分析其临床使用的可能性。结果：Vitapan 3D-Master比色板的26个色片在三维色空间中的明度轴上呈5个层面分布，在2、3、4层面内，6个色片因色调和彩度的不同围绕中间色片呈等距形环分布；L1．5和L2．5色片在组内色空间的色调值偏几黄色，R1．5和R2．5色片的色调值偏向红色，MR1－3侧介于两者之间，结论：Vitapan 3D-Master比色板较完善和等距离和覆盖了牙齿颜色空间，确保了颜色、交流和复制的准确性。     

特殊色牙与Vita比色板色彩的比较研究

目的 比较特殊色牙与Vitapan classical比色板(简称Vita比色板)色彩的差异以指导临床应用。方法 应用ShadeEye—NCC电脑比色仪测定129例特殊色牙患者前牙及Vita比色板的色彩。结果 Vita比色板中缺乏红色系的色片；特殊色牙的色彩为较暗的高饱和度偏红色。结论 特殊色牙的色彩与Vita比色板不匹配；在没有电脑比色仪的情况下，可以选Vita比色板中D色调适当加红制作烤瓷的底色。