Tooth Color Measurement Using Chroma Meter: Techniques, Advantages, and Disadvantages

2003 ◽  
Vol 15 (s1) ◽  
pp. S33-S41 ◽  
Author(s):  
L.I. YIMING
Keyword(s):  
Color Measurement ◽  
Tooth Color ◽  
Advantages And Disadvantages

scholarly journals The reproducibility of electronic color measurements of the marginal gingiva

2020 ◽  
Vol 25 (1) ◽  
pp. 145-150
Author(s):  
Henning Staedt ◽  
Eva Mally ◽  
Herbert Scheller ◽  
Stefan Wentaschek ◽  
Peer Wolfgang Kämmerer ◽  
...  
Keyword(s):  
Color Difference ◽  
Color Measurement ◽  
Tooth Color ◽  
Color Coordinates ◽  
Measurement Systems ◽  
Color Determination ◽  
Determination System ◽  
The Mean ◽  
Measurement Devices

Abstract Introduction This study evaluated the reproducibility of electronic color determination system evaluations of the marginal gingiva, which could be important for adhesive cervical fillings or prosthetic restorations that imitate the gingiva. Material and methods In 50 subjects, the L*, a*, and b* color coordinates were evaluated five times at a point in the marginal area of a central incisor using different electronic color determination systems: (SP) Shadepilot, (ES) Easyshade, (CE) Crystaleye, and (SV) X-Rite. The mean color difference (ΔE) and its standard deviation between the five measurements from each participant were calculated separately for each device. Further ICC for interdevice reliability was determined. Results The L*, a*, and b* color coordinates and ΔE values differed significantly among the systems (p < 0.001). Within each patient and measurement system, ΔE ranged from 1.4 to 3.2 (SD 1.1–2.5), L* from 2.6 to 5.7 (SD 2.6–5.7), a* from 11.9 to 21.3 (SD 3.6–3.9), and b* from 15.1 to 28.9 (SD 1.7–4.3). Interdevice reliability ranged between 0.675 and 0.807. Conclusions Color determination of the marginal gingiva using the electronic tooth color determination systems tested herein showed limited reproducibility. The results obtained with the different measurement systems differed enormously. Clinical relevance These results show that the electronic color measurement devices tested allow no high reproducible determination of color coordinates of the marginal gingiva.

Correlation Among Methods to Measure Tooth Color in Clinical Trials Evaluating Tooth Bleaching

2019 ◽  
Vol 1 (1) ◽  
pp. 46-52 ◽  
Author(s):  
André Luis Faria-e-Silva
Keyword(s):  
Repeated Measures ◽  
Color Change ◽  
Correlation Coefficients ◽  
Wilcoxon Test ◽  
Tooth Bleaching ◽  
Color Measurement ◽  
Tooth Color ◽  
Color Changes ◽  
Assessment Time ◽  
Shade Guide

<P>Objective: This study aimed to assess possible differences in results provided by two shade guides and a spectrophotometer used to measure the color changes during tooth bleaching. </P><P> Methods: Fifty-six patients underwent two sessions of in-office tooth bleaching with a 35% hydrogen peroxide with a week of an interval between them. The color evaluation was performed using shade match with two guide scales (Vita Classical, and Vita Bleach Guide) and a spectrophotometer providing CieLab data. The color was assessed at baseline and 7 days after each session, and 30 days after the last session. Data from scales were arranged in scores according to lightness (lowest to highest) and the color changes were calculated based on baseline data. For CieLab data, &#916;L, &#916;a, &#916;b, and &#916;E were calculated for each assessment time. Differences between the color changes observed in each session were assessed by Wilcoxon test (&#945; = 0.05). Friedman`s test and One-way repeated measures ANOVA were used to analyze color changes among the assessment times. Spearman`s test was used to evaluate the correlation between the shade guide scores and data from Cielab. </P><P> Results: All methods of color measurement demonstrated any additional effect of second bleaching session on color change, and stable color after 30 days (p < 0.001 for all methods). Both shade guide scales presented low correlation coefficients with &#916;L, and moderate coefficients with &#916;b, Δa, and &#916;E. </P><P> Conclusion: Despite the weak/ moderate correlation among the methods used to measure tooth color, all methods showed similar results of tooth bleaching effectiveness.</P>

scholarly journals Evaluating the accuracy of tooth color measurement by combining the Munsell color system and dental colorimeter

2012 ◽  
Vol 28 (9) ◽  
pp. 490-494 ◽  
Author(s):  
Jiun-Yao Chang ◽  
Wen-Cheng Chen ◽  
Ta-Ko Huang ◽  
Jen-Chyan Wang ◽  
Po-Sung Fu ◽  
...  
Keyword(s):  
Color Measurement ◽  
Tooth Color ◽  
Color System

Design of tooth color measurement system based on silicon double P-N junction color sensor

2009 ◽  
Vol 4 (3) ◽  
pp. 318-322
Author(s):  
Zengliang Shi ◽  
Dali Liu ◽  
Yu Wang ◽  
Xi Chen ◽  
Shiying Bai ◽  
...  
Keyword(s):  
Measurement System ◽  
Color Measurement ◽  
Tooth Color ◽  
Color Sensor

scholarly journals Reliability of Two Color Selection Devices in Matching and Measuring Tooth Color

2011 ◽  
Vol 12 (1) ◽  
pp. 19-23 ◽  
Author(s):  
Carmen Llena ◽  
Esther Lozano ◽  
Jose Amengual ◽  
Leopoldo Forner
Keyword(s):  
Correlation Coefficient ◽  
Clinical Significance ◽  
Color Measurement ◽  
Tooth Color ◽  
B Values ◽  
Color Selection ◽  
Color Changes ◽  
Measurement Devices ◽  
Shade Guide ◽  
Paired T Test

ABSTRACT Objective The objective of this study was to investigate the intra and interdevice reliability of two tooth color measurement devices: EasyShade (ES) and SpectroShade Micro (SSM). Materials and methods Tooth color was measured in six maxillary and mandibular. L*, a* and b* values and shade matches to VITA Classical and Vitapan 3D-Master shade guide systems were determined for all teeth. ÄE was assessed. Paired t-test and correlation coefficient (ICC) were used. Results Intradevices no significant differences (p > 0.05) were found between L*, a*, b*. Interdevice L* and b* were significantly higher for ES (p < 0.05), while a* was significantly higher for SSM (p < 0.05). ÄE showed no significant interdevice difference (p > 0.05). Intradevices ICC values were higher for ES but not significant (p > 0.05). Discussion The null hypotheses that they present no differences in their color measuring within devices or shade systems is accepted, but the results allow to reject the null hypotheses that they present no differences in their color measuring or shade systems between devices. Conclusion Both EasyShade (ES) and SpectroShade Micro (SSM) show excellent repeatability and so they can be used in office to evaluate tooth color or to assess color changes after treatment. Clinical significance Dental color can be diagnosed using dental spectrophotometers, allowing to detect in an objective way therapeutic dental color changes. How to cite this article Llena C, Lozano E, Amengual J Forner L. Reliability of Two Color Selection Devices in Matching and Measuring Tooth Color. J Contemp Dent Pract 2011; 12(1):19-23.

Experimental investigations into visual and electronic tooth color measurement

2011 ◽  
Vol 56 (2) ◽  
pp. 115-122 ◽  
Author(s):  
Anja Ratzmann ◽  
Anja Treichel ◽  
Gabriele Langforth ◽  
Tomasz Gedrange ◽  
Alexander Welk
Keyword(s):  
Color Measurement ◽  
Experimental Investigations ◽  
Tooth Color

scholarly journals Comparative characteristics of conventional visual methods and instrumental digital methods for tooth color determination

2020 ◽  
Vol 24 (5) ◽  
pp. 344-354
Author(s):  
M. M. Hasasna ◽  
Andrey V. Akulovich
Keyword(s):  
Quality Criteria ◽  
Color Measurement ◽  
Target Color ◽  
Visual Methods ◽  
Tooth Color ◽  
Color Determination ◽  
Important Quality ◽  
Shade Matching ◽  
Digital Methods ◽  
Instrumental Methods

Shade matching is a challenging step and the major objective in esthetic and restorative dentistry. On many occasions, the production of the accurate target color will not be achieved due to errors in the registration of the target color, or errors in composing the appropriate color of the restoration in the dental laboratory. Thus, the accurate and correct shade matching of tooth and restoration is one of the most important quality criteria for the patient and the key to successful results for the dentist. Conclusion: Spectrophotometers, colorimeters, intraoral scanners, and imaging systems are useful and relevant tools for tooth color measurement and analysis, and for the quality control of color reproduction. The combination of visual and instrumental methods of tooth color determination will complement each other, leading toward predictable esthetic results.

Recent Advances in Color and Whiteness Evaluations in Dentistry

2019 ◽  
Vol 1 (1) ◽  
pp. 23-29 ◽  
Author(s):  
María M. Pérez ◽  
Oscar E. Pecho ◽  
Razvan Ghinea ◽  
Rosa Pulgar ◽  
Alvaro Della Bona
Keyword(s):  
Clinical Performance ◽  
Dental Materials ◽  
Color Space ◽  
Color Difference ◽  
Color Measurement ◽  
Tooth Color ◽  
Dental Research ◽  
Color Science ◽  
Difference Formula ◽  
Color Differences

Background: The final goal of color measurement or shade specification in dentistry is the reproduction by prosthetic materials of all important appearance characteristics of natural oral structures. The application of color science in dentistry is an objective way to measure and evaluate such structures and dental materials in clinical practice and dental research. Methods: Literature on color science was reviewed to present new metrics to evaluate color differences of dental materials and dental structures. Visual acceptability and perceptibility values of color differences are reviewed and new whiteness indexes to describe whiteness in dentistry are presented. Results: In the last decade, the CIELAB 50:50% perceptibility and acceptability thresholds were set to 1.2 and 2.7, respectively, and the CIEDE2000 50:50% perceptibility and acceptability thresholds were set to 0.8 and 1.8. The CIEDE2000 color-difference formula became increasingly popular in dentistry. Developments in color science have led to the description of tooth whiteness and changes in tooth whiteness based on whiteness indexes, with the most relevant being the WID whiteness index, which is a customized index based in CIELAB color space. Conclusion: The application of color science in dentistry has allowed the precise description of tooth color and whiteness. The revised and new CIEDE2000 color-difference formula is expected to fully replace the outdated CIELAB formula in almost all dental applications. Recent psychophysical studies have reported values of visual thresholds and new whiteness indexes, which can serve as quality control tools to guide the selection of esthetic dental materials, evaluate clinical performance, and interpret visual and instrumental findings in clinical dentistry, dental research, and subsequent standardization.

Cryogenic atomic force microscopy

1991 ◽  
Vol 49 ◽  
pp. 54-55
Author(s):  
K. A. Fisher ◽  
M. G. L. Gustafsson ◽  
M. B. Shattuck ◽  
J. Clarke
Keyword(s):  
Room Temperature ◽  
Rapid Freezing ◽  
Cryogenic Temperatures ◽  
Soft Or ◽  
Electrically Conductive ◽  
Force Microscopy ◽  
Flexible Molecules ◽  
Advantages And Disadvantages ◽  
Atomic Force ◽  
Chemical Perturbation

The atomic force microscope (AFM) is capable of imaging electrically conductive and non-conductive surfaces at atomic resolution. When used to image biological samples, however, lateral resolution is often limited to nanometer levels, due primarily to AFM tip/sample interactions. Several approaches to immobilize and stabilize soft or flexible molecules for AFM have been examined, notably, tethering coating, and freezing. Although each approach has its advantages and disadvantages, rapid freezing techniques have the special advantage of avoiding chemical perturbation, and minimizing physical disruption of the sample. Scanning with an AFM at cryogenic temperatures has the potential to image frozen biomolecules at high resolution. We have constructed a force microscope capable of operating immersed in liquid n-pentane and have tested its performance at room temperature with carbon and metal-coated samples, and at 143° K with uncoated ferritin and purple membrane (PM).

A conduction-cooled stage for high-resolution Cryo-SEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1282-1283
Author(s):  
John G. Sheehan
Keyword(s):  
High Resolution ◽  
Liquid Nitrogen ◽  
Mechanical Stability ◽  
Cooling System ◽  
Cold Trap ◽  
Nitrogen Gas ◽  
Particulate Suspensions ◽  
Advantages And Disadvantages ◽  
Convection Cooling ◽  
Styrene Butadiene

The goal is to examine with high resolution cryo-SEM aqueous particulate suspensions used in coatings for printable paper. A metal-coating chamber for cryo-preparation of such suspensions was described previously. Here, a new conduction-cooling system for the stage and cold-trap in an SEM specimen chamber is described. Its advantages and disadvantages are compared to a convection-cooling system made by Hexland (model CT1000A) and its mechanical stability is demonstrated by examining a sample of styrene-butadiene latex.In recent high resolution cryo-SEM, some stages are cooled by conduction, others by convection. In the latter, heat is convected from the specimen stage by cold nitrogen gas from a liquid-nitrogen cooled evaporative heat exchanger. The advantage is the fast cooling: the Hexland CT1000A cools the stage from ambient temperature to 88 K in about 20 min. However it consumes huge amounts of liquid-nitrogen and nitrogen gas: about 1 ℓ/h of liquid-nitrogen and 400 gm/h of nitrogen gas. Its liquid-nitrogen vessel must be re-filled at least every 40 min.

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