Dental Shade Matching and Value Discernment Abilities of First-Year Dental Students.

PURPOSE: To determine if Farnsworth-Munsell 100 Hue Test, Perceptual Ability Test, gender, age, ethnicity, and time predict dental shade matching and value discernment in first-year dental students. MATERIALS AND METHODS: Farnsworth-Munsell 100 Hue Test was administered to 95 first-year-dental students beneath a Judge II booth (color temperature of 6500°K, and color rendering index of 90). Students also arranged 16 masked shade tabs from a Vita Classic shade guide by value (lightest to darkest) and matched together 16 pairs of masked shade tabs from two Vita Classic shade guides. Ethnicity, age, Perceptual Ability Test scores, gender, and time to complete the tests were recorded. Associations and correlations were investigated using chi-square, Tukey-Kramer HSD, standard least square, and multilinear regression (p < 0.05). RESULTS: Total error scores on the Farnsworth-Munsell 100 Hue Test ranged from 0 to 144. Forty-eight students exhibited superior color acuity, 45 average, and two poor. The mean number of correct answers for matching shade tabs together was 11.6, and 6.1 for arranging the shade tabs by value. Females performed statistically better than males on the Farnsworth-Munsell 100 Hue Test and shade tab matching. Better color discrimination identified by lower total error scores on the Farnsworth-Munsell 100 Hue Test was directly correlated to greater ability to match shade tabs together. Perceptual Ability Test scores had slight significance. As the scores increased there was slightly better performance on the Farnsworth-Munsell 100 Hue Test. Older participants performed better than younger subjects on the value test. No other correlations were significant for any of the tests. CONCLUSIONS: Females and individuals who performed better on the Farnsworth-Munsell 100 Hue Test have improved dental shade-matching ability.

Lighting conditions used during visual shade matching in private dental offices.

STATEMENT OF PROBLEM: To our knowledge, no data are available on the actual lighting that is used for visual shade matching in private dental offices. PURPOSE: The purpose of this study was to determine the shade matching practices and interest in continuing education in dental practices and to determine the quantity and quality of the ambient lighting used during visual shade matching in a sample cohort of dentists in private practices. MATERIAL AND METHODS: Thirty-two private practices were enrolled, and each completed a 1-page survey on the clinic's shade matching practices. A spectrophotometer was used to measure the ambient lighting in each practice, collecting data on color temperature (Kelvin), color rendering index (CRI), and light intensity (foot candles/fc). A 2-sided nonparametric sign test was used to compare the true median color temperature with the standard (5500°K). A 1-sided t test was used to compare the CRI with the standard (CRI >90) (α=.05 for all statistical analyses). RESULTS: All dental practitioners surveyed used mainly visual shade matching in their practices. Of those, 87.5% showed interest in attending continuing education on this topic, with 56.3% preferring a clinical demonstration course. The mean color temperature was 4152.9°K and was significantly different from the standard 5500°K (P<.001). The 1-sided t test indicated that the mean CRI was less than 90 (P=1). The 95% confidence interval for the intensity was 80.7 to 111.6 fc. CONCLUSIONS: The ambient light in the majority of the 32 dental private practices measured was not ideal for visual shade matching.

Influence of light source, polarization, education, and training on shade matching quality.

STATEMENT OF PROBLEM: Many factors influence the quality of shade selection, and isolating how significantly each of these factors influences results is difficult. PURPOSE: The purpose of this in vitro study was to compare results of shade matching using handheld lights with or without a polarizing filter with results obtained using a professional viewing booth and to analyze the influence of education and training on shade selection outcome. MATERIAL AND METHODS: A total of 96 third-year dental students (evaluators) were randomly separated into 4 groups. Each group was assigned 1 of 2 handheld shade-matching devices (lights) with or without a polarizing filter. Each group performed a shade matching exercise using the handheld light or a professional viewing booth. The exercise consisted of matching shade tabs placed in a typodont to a commercial shade guide. Each group repeated this procedure 4 times over a 9-week period. A lecture on shade matching was presented at the fifth week of the study, between "before" and "after" shade matching procedures. RESULTS: Shade matching scores with handheld lights (7.8) were higher than scores of shade matching with the viewing booth (7.2). The mean scores for before (7.2) and after (7.8) shade matching (with education and training in between) were significantly different. The combined effect of light and education and training improved the shade matching score by 1.2, from 6.8 in the before sessions using the viewing booth to 8.0 in the after sessions using handheld lights. A 21% increase in the number of evaluators who selected 1 of 4 best matches was recorded, 10% for handheld lights versus viewing booth after education and training versus before sessions and 11% between after sessions using handheld lights versus before sessions using viewing booth. CONCLUSIONS: Within the limits of the study, the shade matching scores with handheld lights were significantly better than the results obtained using a viewing booth (P<.01). Using a handheld light with or without a polarizing filter did not influence shade matching results. Mean shade matching scores were significantly better after education and training (P<.01). Light combined with education and training resulted in the greatest increase in shade matching quality.

A clinical study relating CIELCH coordinates to the color dimensions of the 3D-Master System in a Spanish population.

STATEMENT OF PROBLEM: The 3D-Master System comprises 26 physical shade tabs and intermediate shades. Determining the relationship among all the groups of lightness, chroma, and hue of the 3D-Master System (Vita Zahnfabrik) and the L*, C*, and h* coordinates is important, because according to the manufacturer, 2 Toothguide 3D-Master shades need to be mixed in a 50:50 ratio to create an intermediate shade. PURPOSE: The purpose of the study was to relate the lightness, chroma, and hue groups of the 3D-Master System with the polar coordinates of the CIELAB chromatic space, L*, C*, and h*, and to quantify the shades tabs and intermediate shades of the 3D-Master System according to color coordinates. MATERIAL AND METHODS: The middle third of the facial surface of a natural maxillary central incisor was measured with an Easyshade Compact spectrophotometer (Vita Zahnfabrik) in 1361 Spanish participants aged between 16 and 89 years. Natural tooth color was recorded in the 3D-Master nomenclature and in the CIE L*, C*, and h* coordinates system. The program used for the present descriptive statistical analysis of the results was SAS 9.1.3. RESULTS: In the L* variable, the minimum was found at 47.0 and the maximum at 91.3. In the C* variable, the minimum was found at 5.9 and the maximum at 49.8, while for h*, the minimum was 67.5 degrees and the maximum 112.0 degrees. CONCLUSIONS: Despite the limitations of this study, the 3D-Master System was found to be arranged according to L*, C*, and h* coordinates in groups of lightness, chroma, and hue. The corresponding groups of lightness, chroma, and hue can be estimated on the basis of L*, C*, and h* coordinates.

Shade determination using camouflaged visual shade guides and an electronic spectrophotometer.

The aim of the present study was to compare a camouflaged visual shade guide to a spectrophotometer designed for restorative dentistry. Two operators performed analyses of 66 subjects. One central upper incisor was measured four times by each operator; twice with a camouflaged visual shade guide and twice with a spectrophotometer Both methods had acceptable repeatability rates, but the electronic shade determination showed higher repeatability. In general, the electronically determined shades were darker than the visually determined shades. The use of a camouflaged visual shade guide seems to be an adequate method to reduce operator bias.

Perceptibility and acceptability thresholds for color differences of light and dark maxillofacial skin replications.

The aim of this study was to assess the perceptibility and acceptability thresholds of maxillofacial silicones for light and dark skin colors and to evaluate the effect of gender and professional experience on these thresholds. Two different sets of specimens (as light and dark) each, consisting of 14 (25 × 25 × 6-mm3) silicone skin replications, were produced. Four specimens of each set were produced from the same silicon mixture of the relevant set and polymerized simultaneously to provide standardized fabrication conditions. These 4 light/dark specimens were assigned as "baseline color specimens (BCs)" in each set, while the other 10 specimens were produced with a color difference level that increased gradually from BC. These stepped levels were obtained by controlled increasing of the pigment concentration in the relevant baseline silicon mixture. Color difference levels of specimens were calculated by using the CIELAB and CIEDE2000 formulas. Observers comprised of 3 different professional experiences as first-year dental students, interns, and dentists (n = 30/group, gender-balanced) were included. Combinations consisting of 5 specimens with 4 BCs and 1 different color were shown to the observers to assess whether the color difference was perceptible or acceptable. Perceptibility and acceptability percentages were regressed with color difference levels to estimate the best fit curve and confidence intervals were calculated (α = 0.05). The highest estimation of the coefficient of determination (R2) was found in the cubic curve for all parameters. A significant difference was found between the light and dark colors. The perceptibility thresholds (ΔE*ab/ΔE00) were 0.8/0.59 and 2.63/1.75 for light and dark colors, respectively. The acceptability thresholds (ΔE*ab/ΔE00) were 3.35/2.25, 10.07/7.04 for light and dark colors, respectively. No significant differences were found between gender and among experience groups concerning visual thresholds. Regardless of gender and experience, observers could perceive color differences more easily in light skin colors.

Spectrophotometric assessment of peri-implant mucosa after restoration with zirconia abutments veneered with fluorescent ceramic: a controlled, retrospective clinical study.

OBJECTIVES: The purpose of this study was to investigate the optical appearance of the soft tissue labial to dental implants restored with fluorescent ceramic-veneered zircona abutments. It was hypothesized that the tested abutment design leads to an increased brightness in the marginal peri-implant tissue, which does not differ from that of natural teeth. Moreover, a reduction of the color difference that has been reported from other abutment materials was expected. MATERIALS AND METHODS: A total of 12 patients with single titanium implants in the maxillary anterior region were recruited. All implants (N = 12) were restored with zirconia abutments veneered with fluorescent ceramic and full-ceramic crowns. Color measurements of the peri-implant mucosa at the test sites were made of the facial aspect of the teeth using a Spectroshade-spectrophotometer. The gingiva of a contralateral or adjacent natural tooth served as a control. Color data (CIE-L*a*b* color coordinates) were obtained in five incremental areas of 1 × 2 mm in both test and control sites. ∆E-values were calculated from the ΔL*, Δa* and Δb* values for each patient. RESULTS: Data acquisition from the test site demonstrated lower mean values of L*, a* and b* than the control site. Statistical significance between the test site and control site was reached in the L* values only in the second of the five incremental areas (P < 0.05, Wilcoxon test). However, discrepancies in a*- and b*-values reached a statistically significant difference in the incremental areas 1, 2 and 4, and in b* in area 5 (P < 0.05, Wilcoxon test). Medians of the ∆E-values in all five increments were found to be higher than the clinical perceptual threshold of 3.7. However, considering the original data, five individual patients did not reach the threshold in increment 1 and 2, two in increment 3 and three in increment 4. None of the patients showed lower ∆E-values than the perceptual threshold of 3.7 in increment 5, which had the largest distance from the gingival margin. CONCLUSION: The tested abutment design leads to a peri-implant soft tissue color that, in the critical marginal area, in five of 12 patients did not statistically differ from the tissue of the gingiva of natural teeth. Particularly, the brightness of the peri-implant soft-tissue seemed to be more adapted to the natural situation using a fluorescent abutment design.

Spectrophotometric evaluation of a novel aesthetic composite resin with respect to different backgrounds in vitro.

Tooth colour matching of composite materials is often a common problem caused by a dark background from the oral cavity. Therefore, the aim of the study was to evaluate a novel aesthetic composite material and to assess the influence of white and black backgrounds. Tooth shades of 30 freshly extracted upper front teeth were determined using a spectrophotometer (SpectroShade™) both against a white and a black background. Two class IV cavities in each tooth were prepared and restored using three different composite resins: Arabesk™ (AB), Synergy™ (SE) and the novel material Amaris™ (AM). After water storage for 1 week, differences in hue, saturation and lightness were measured to assess changes from baseline. After thermocycling, teeth were evaluated once more to assess the reliability of the treatment outcomes. Compared to baseline, differences in hue were not statistically different for all restoration materials (p > 0.05) with respect to the white or black background. Delta values for saturation were not different in the AB and AM groups (p > 0.05) with higher values for SE (p < 0.05). Regarding lightness, values in the AB group were statistically higher (p < 0.05) than values for AM with no difference between AB and SE and with no difference between the AM and SE groups (p > 0.05). Employing the novel aesthetic composite resin, a minor impact of white and black backgrounds could be observed compared to conventional composites. Therefore, it might effectively mask the dark background from the oral cavity.

A clinical study to correlate maxillary anterior natural teeth with that of the commercially available acrylic and porcelain shade guides.

The success of the dental treatment as perceived by our patients is often preferentially evaluated on the appearance of the restoration. Usually visual determination is unreliable and inconsistent, complicated by the inability of the shade guide to cover the entire dental color range and also there is lack of logical order of arrangement of the tabs. Hence a clinical study is planned to perform visual shade selection in standardized conditions to correlate the shades of maxillary anterior natural teeth in adult subjects of Davengere district origin to one acrylic and three porcelain shade guides commercially available in India.

Incisal translucency of vital natural unrestored teeth: a clinical study.

INTRODUCTION: Understanding the distribution of incisal translucency will provide clinicians a guide to use this knowledge to improve the esthetic replication of anterior restorations. The aim of this study is to investigate the distribution of incisal translucency of unrestored vital natural maxillary central, lateral, and canine vital teeth from a stratified population in different age, gender, and race. MATERIALS AND METHODS: A total of 120 subjects were recruited for this study. Six subjects with equal gender balance from four racial/ethnic groups (White, Black, Asian, and others) were recruited from each of the following age groups: 18 to 29 years, 30 to 39 years, 40 to 49 years, 50 to 59 years, and 60 to 85 years. Potential subjects were clinically screened to determine if three specific anterior teeth (maxillary central incisor, lateral incisor, and canine) were non-restored, natural permanent teeth free from external staining or bleaching. A digital imaging and shade analysis device was used to measure tooth translucency. RESULTS: Statistically significant interaction (p < 0.001) was found for the groups. The interaction between race and gender was not statistically significant (p = 0.485). However, the interaction between race and age (p = 0.03), age and gender (p = 0.015), and among age, race, and gender (p < 0.001) was found statistically significant according to the analysis of variance test results. The interaction between race and gender was not statistically significant (p = 0.485).

Colour match between porcelain and porcelain-repairing resin composites.

The aim of this study was to evaluate the differences in colour between dental porcelain and porcelain-repairing resin composites. Porcelain discs were fabricated using four dentine shades in 1mm and 2mm thicknesses. Another series of discs was fabricated in 1mm and 2 mm thicknesses using three different brands of composite. Four single shades were used for the 1mm thick discs, and four single and 12 combined shades for the 2mm thick discs. The colour was measured using a spectrophotometer and colour differences deltaE* were calculated between samples. Colour differences were in the range of (deltaE* = 3.5-26.9), above the accepted threshold for perceptibility (deltaE* > 1) with a number above the threshold for what is considered to be clinically acceptable (deltaE* > 5.5). Improvements in colour match were seen for certain shade combinations of repairing composites, in contrast to when a single shade of composite was used.

Accuracy of shade matching performed by colour blind and normal dental students using 3D Master and Vita Lumin shade guides.

The purpose of this study was to investigate whether 3D Master or VitaLumin shade guides could improve colour selection in individuals with normal and defective colour vision. First, colour perception of 260 dental students was evaluated. Afterwards, 9 colour blind and 9 matched normal subjects tried to detect colours of 10 randomly selected tabs from each kit and the correct/false answers were counted. Of the colour-defective subjects, 47.8% and 33.3% correctly detected the shade using 3D Master and VitaLumin, respectively. These statistics were 62.2% and 42.2% in normal subjects. In normal participants, but not in colour blind ones, 3D Master significantly improved shade matching accuracy compared to VitaLumin.

Development of digital shade guides for color assessment using a digital camera with ring flashes.

Digital photographs taken with cameras and ring flashes are commonly used for dental documentation. We hypothesized that different illuminants and camera's white balance setups shall influence color rendering of digital images and affect the effectiveness of color matching using digital images. Fifteen ceramic disks of different shades were fabricated and photographed with a digital camera in both automatic white balance (AWB) and custom white balance (CWB) under either light-emitting diode (LED) or electronic ring flash. The Commission Internationale d'Éclairage L*a*b* parameters of the captured images were derived from Photoshop software and served as digital shade guides. We found significantly high correlation coefficients (r² > 0.96) between the respective spectrophotometer standards and those shade guides generated in CWB setups. Moreover, the accuracy of color matching of another set of ceramic disks using digital shade guides, which was verified by ten operators, improved from 67% in AWB to 93% in CWB under LED illuminants. Probably, because of the inconsistent performance of the flashlight and specular reflection, the digital images captured under electronic ring flash in both white balance setups revealed less reliable and relative low-matching ability. In conclusion, the reliability of color matching with digital images is much influenced by the illuminants and camera's white balance setups, while digital shade guides derived under LED illuminants with CWB demonstrate applicable potential in the fields of color assessments.

Color change during the surface preparation stages of metal ceramic alloys.

STATEMENT OF PROBLEM: Even though metal ceramic restorations (MCRs) are widely used by clinicians, the influence of the metal on the color of overlaying porcelain is unknown. PURPOSE: The purpose of this study was to analyze the color alterations of different types of metal ceramic alloys during several stages of metal surface preparation and to determine the effect of those changes on the resulting color of opaque porcelain (OP). MATERIAL AND METHODS: Seven different types of alloys (3 base metal, 3 noble, and 1 high noble) were used to prepare disk-shaped specimens (1 mm × 10 mm, n=3), followed by OP application (0.1 mm). L*a*b* values of specimens were recorded after different stages of metal surface preparation (ingot, after casting, after oxidation, and after the OP application) in addition to the shade tab of OP B1 (target shade). L*a*b* values of alloys were measured from the ingot structure to the OP application stage and statistically analyzed (Repeated measures ANOVA, and Bonferroni corrected paired t test, α=.05). L*a*b* values of OP applied groups and the OP shade tab (target shade) were analyzed (1-way ANOVA with Dunnett's multiple comparison test, α=.05). The color differences of the target shade both before and after OP application were calculated and statistically analyzed (1-way ANOVA, Ryan-Einot-Gabriel-Welsch Multiple Range Test, α=.05). RESULTS: The L* values of all alloys changed significantly after each stage except for 2 alloys (V-Deltaloy SF (N-VDSF)) and (Gnathos Plus (HN-GP)) after casting and airborne-particle abrasion (P<.05). The a* value of all alloys increased after casting. Changes in the a* coordinate were significant except for one of the base metal alloys (P<.05). The a* coordinate changes of alloys showed variation in direction after oxidation and OP application (P<.05). The b* coordinate changes of alloys showed variation in direction after each stage (P<.05). The L*a*b* values of some OP applied alloys were significantly different from that of the OP shade tab (P<.05). Color difference values (ΔE (OP applied alloy-target shade)) of 2 OP-applied alloys (Cerapall 2 (N-CP2) and Ceradelta (N-CD)) were significantly different (P<.05) and higher than the other OP-applied alloys. CONCLUSIONS: The achromatic color behavior of different alloys was all in the same direction at all metal surface preparation stages. The chromatic behavior of the different alloys was primarily towards the same direction after casting and airborne-particle abrasion, whereas it varied after oxidation and OP application. The color difference of OP for all alloys, regardless of their type, was not visually perceivable when compared to the target shade (ΔE<2.6).

Effects of shade tab arrangement on the repeatability and accuracy of shade selection.

STATEMENT OF PROBLEM: Appropriate and repeatable shade matching using visual shade selection remains a challenge for the restorative dentist. PURPOSE: The purpose of this study was to evaluate the effect of different arrangements of a shade guide on the repeatability and accuracy of visual shade selection by restorative dentists. MATERIAL AND METHODS: Three Vitapan Classical shade guides were used for shade selection. Seven shade tabs from one shade guide were used as target shades for the testing (A1, A4, B2, B3, C2, C4, and D3); the other 2 guides were used for shade selection by the subjects. One shade guide was arranged according to hue and chroma and the second was arranged according to value. Thirteen male and 22 female restorative dentists were asked to match the target shades using shade guide tabs arranged in the 2 different orders. The sessions were performed twice with each guide in a viewing booth. Collected data were analyzed with Fisher's exact test to compare the accuracy and repeatability of the shade selection (α=.05). RESULTS: There were no significant differences observed in the accuracy or repeatability of the shade selection results obtained with the 2 different arrangements. When the hue/chroma-ordered shade guide was used, 58% of the shade selections were accurate. This ratio was 57.6% when the value-ordered shade guide was used. The observers repeated 55.5% of the selections accurately with the hue/chroma-ordered shade guide and 54.3% with the value-ordered shade guide. CONCLUSIONS: The accuracy and repeatability of shade selections by restorative dentists were similar when different arrangements (hue/chroma-ordered and value-ordered) of the Vitapan Classical shade guide were used.

Aesthetic colour performance of plastic and ceramic brackets -- an in vitro study.

OBJECTIVE: To evaluate the aesthetic colour performance (colour blending) of plastic and ceramic brackets by determining the colour changes of shade guide tabs before and after bracket placement. DESIGN: In vitro, laboratory study. MATERIALS AND METHODS: Four plastic and four ceramic brackets were investigated (n=5). Brackets were placed on the labial surface of the A1 and A4 tabs of a Vitapan classic shade guide. The colours of the areas corresponding to the central and inferior areas of the brackets were measured before and after bracket placement according to the CIELAB colour scale with a spectroradiometer. Changes in colour (ΔE*(ab)) and colour coordinates (ΔL*, Δa*, Δb* and ΔC*(ab)) of the tabs after bracket placement were calculated. RESULTS: Colour changes in the central and inferior areas were in the ranges of 5·6-11·1 and 4·3-12·3 ΔE*(ab) units, respectively. Changes in colour and colour coordinates were influenced by shade tab colour and bracket brand (P<0·05). Compared to A1 tab, ΔE*(ab), Δa*, Δb* and ΔC*(ab) values on A4 tab were significantly higher (P<0·01). The hybrid polymer bracket and glass reinforced plastic bracket induced the smallest colour changes in the central and inferior areas. CONCLUSIONS: All the investigated aesthetic brackets induced clinically unacceptable (ΔE*(ab)>5·5) or perceptible (ΔE*(ab)>2·6) colour changes when placed on the shade tabs. Aesthetic colour performance of brackets on the less chromatic and lighter tab was better than that on the more chromatic and dark tab. High translucency of bracket alone did not lead to better aesthetic colour performance.

Reliability of two color selection devices in matching and measuring tooth color.

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. ΔE 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). ΔE 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.

An audit of shade reproduction of fixed metal ceramic prostheses.

This investigation aimed to evaluate the colour difference between metal ceramic restorations and their corresponding shades and any reasons for a colour mismatch in the dental laboratory. The colour of 50 consecutive metal ceramic restorations produced in a laboratory was measured using a spectrophotometer and compared to the shade tabs. Colour reproduction was optimal at porcelain thicknesses between 1.4-1.6 mm, varied between technicians within the same laboratory and was better for shades in the 2M group. Most crowns were above the threshold for a clinically acceptable shade match and almost all crowns were lighter than the corresponding shade tab.

New technology: mandatory, elective, or hype?

If you were to buy all of the technologies that are currently advertised as being important, it would be financially stressful. In addition, you may not find that you would use all of them with equal enthusiasm. In our opinion, some new technologies are mandatory for current practice, while others are primarily elective. Only you can decide which technology is desirable to better treat your patients and make dentistry more enjoyable for you and your staff. Incorporation of the right new technology into your practice will excite you, your staff, and your patients, stimulate your interest in dentistry, and potentially provide higher quality dentistry. The money you spend on the technology of your choice will be well spent if you evaluate each concept carefully and thoroughly before buying it.

Comparison of various resin composite shades and layering technique with a shade guide.

PURPOSE: The purpose of this study was to compare the final shade of different shades of composites (enamel shades) over a white backing (WB) and black backing (BB), and a layering technique (enamel over dentin composite) with the corresponding Vita Classical Shade tabs (VST). MATERIALS AND METHODS: Composite disk specimens enamel (N = 5) shades B1, B2, A1, and A2, and dentin (N = 1) shades A1, A2, and A3 were made. The color of the VST B1, B2, A1, and A2, enamel shade disks, and layering composites of the same brand and different brands were assessed using a colorimeter over a WB and BB. The total color difference (DeltaE*(ab) = [(DeltaL*)(2) + (Deltaa*(ab))(2) + (Deltab*(ab))(2)](1/2)) between the VST and the corresponding resin composite was calculated. The results were analyzed by one-way analysis of variance/Tukey's test (p < 0.05). RESULTS: Overall, the L*, a*, and b* values of the enamel composite shades were significantly different from the corresponding VST. Only a few layered composites matched the L*, a*, and b* of the keyed VST. Out of the 72 combinations, 20 (28%) resulted in DeltaE*(ab) below the 3.3 clinically perceptible limit. CLINICAL SIGNIFICANCE Composite shades do not match well to the Vita shade guide tabs, even when the layering technique is used. As demonstrated in this study, only a few composites matched the corresponding Vita shade guide tabs. (J Esthet Restor Dent 22:114-126, 2010).