Red-green Color Research Articles

A Study on Prevalence of Colour Vision Defects and Correlation with Sex, Visual Acuity and Blood Groups of the Study Group

Inherited color blindness is a lifelong challenge. While it may limit prospects for certain jobs, most peoplefind ways to adapt to the condition. Colour vision defect is usually for red-green colour and it is X-linkedrecessive trait. It is mainly homozygous that develop colour vision defects. Female heterozygous usuallyhave normal vision. Colour vision defects also have a strong genetic component , especially if both parentshave colour vision defects , and people with a particular blood group , and very myopic or hypermetropic, there is a good chance their child will be same. Color blindness is often apparent at a young age whenchildren are learning their colours and goes undetected because as they grow they learn to associate specificcolours with certain objects.For example, they come to know that grass is green, so they call the colour theysee green. If symptoms are very mild, a person may not realize that they don’t see certain colours.

Gene therapy in color vision deficiency: a review.

Color vision deficiencies are a group of vision disorders, characterized by abnormal color discrimination. They include red-green color blindness, yellow-blue color blindness and achromatopsia, among others. The deficiencies are caused by mutations in the genes coding for various components of retinal cones. Gene therapy is rising as a promising therapeutic modality. The purpose of this review article is to explore the available literature on gene therapy in the different forms of color vision deficiencies. A thorough literature review was performed on PubMed using the keywords: color vision deficiencies, gene therapy, achromatopsia and the various genes responsible for this condition (OPN1LW, OPN1MW, ATF6, CNGA3, CNGB3, GNAT2, PDE6H, and PDE6C). Various adenovirus vectors have been deployed to test the efficacy of gene therapy for achromatopsia in animals and humans. Gene therapy trials in humans and animals targeting mutations in CNGA3 have been performed, demonstrating an improvement in electroretinogram (ERG)-investigated cone cell functionality. Similar outcomes have been reported for experimental studies on other genes (CNGB3, GNAT2, M- and L-opsin). It has also been reported that delivering the genes via intravitreal rather than subretinal injections could be safer. There are currently 3 ongoing human clinical trials for the treatment of achromatopsia due to mutations in CNGB3 and CNGA3. Experimental studies and clinical trials generally showed improvement in ERG-investigated cone cell functionality and visually elicited behavior. Gene therapy is a promising novel therapeutic modality in color vision deficiencies.

COLOUR VISION DEFICIENCY AMONG MEDICAL STUDENTS OF CHITWAN

Background: Colour vision is the function of three types of cone pigments present in the retina. Though colours are used for important signs in the medical profession, screening for colour blindness is not paid attention at beginning of a medical career. This study was aimed to assess the presence of colour blindness, if any among the medical students of Chitwan Medical College. Methods: A total of 220 medical students including 127 females and 93 males aged between 16-24 years were examined for colour blindness. Students were shown the complete range of Ishihara’s plates under daylight conditions. The chart was held 75 cm away from the subjects. The types of colour vision deficiency were differentiated with help of key provided with the chart. The data was analyzed by using Statistical Package for the Social Sciences version 20. Results: Among 220 participants, 5(2.27%) were found to have colour vision deficiency. Out of 5colourdeficient students, 4of them were red-green colour vision deficient and 1 of them couldn’t appreciate colour (total colour blindness) within the speculated time for the test. Female partici­pants didn’t have colour vision deficiency while colour vision deficient students were unaware of their colour vision status. Conclusions: Colour vision deficiency affects male than female. Medical students should be screened for colour vision deficiency and made aware of their limitation so that they can take special care in their future clinical practice.

Color stability of orthodontic esthetic archwires- A comparative in vitro study

Objective: To study and evaluate effect of various food products on color stability of orthodontic esthetic archwires at different time period. Materials and Methods: A total of 120 coated esthetic archwires (Teflon and Epoxy Resin) were investigated. They were divided into 4 groups and 8 subgroups. Cumulative discoloring effect of staining agents (aerated drink artificial orange, colgate plax mouth wash, and red wine) and control group in distilled water were analyzed for a period of 21 days and the solution was changed every 7th day. Samples were analyzed with spectrophotometer to obtain the L*, a*, and b* (lightness, red-green, and yellow-blue) color readings. Using these values total color change (?E*) at each level was also calculated. A general linear model (ANOVA and Tukey’s Post Hoc) test was used for statistical comparisons. Results: Significant differences were observed in ?E value of teflon and epoxy resin coated esthetic archwires between the staining agent and the control groups (p?.0001). Among the teflon coated esthetic archwires the ?E value for Artificial orange (aerated drink) (5.61±0.30) was highest indicating that artificial orange discolored the wires most in the inter group followed by the red wine (5.44±0.25), and colgate plax mouthwash (1.31±0.15) the least. Among the epoxy resin coated esthetic archwires the ?E value for red wine (4.52±0.30) was highest indicating that wires in the red wine discolored most. The colgate plax mouthwash (3.54±0.15) and the artificial orange (3.42±0.14) almost stain same. On overall comparision teflon coated and epoxy resin coated, the mean ?E value was statically significant in all the experimental groups. But the epoxy resin coated esthetic archwires were less stained as compare to Teflon coated wires (p value

Color vision assessment‐3. An efficient, two‐step, color assessment protocol

AbstractColor vision tests and multi‐test protocols in current use often fail to detect small changes in red/green (RG) and yellow/blue (YB) color vision due to poor sensitivity. The tests also have low specificity. In this study, we examine how improved understanding of within‐ and inter‐subject variability in RG and YB color vision and accurate assessment of the differences in color thresholds between the least‐sensitive, age‐matched normal trichromats, and the least‐affected deutans and protans can be used to design an efficient color vision screener (CVS) test. To achieve this objective, we examined two extensive data sets from earlier studies and carried out new experiments to provide better estimates of within‐subject variability in color thresholds and to validate the CVS test. The data sets provide essential information on inter‐subject variability, the effects of normal aging on RG and YB thresholds, and the spread in RG color thresholds in deutan and protan subjects. A statistical model was developed to optimize the parameters of the CVS test and to predict the limits of what can be achieved in color assessment. The efficiency and repeatability of the CVS test were then assessed in 84 subjects. The results match model predictions and reveal close to 100% test efficiency. The test takes between 140 and 160 seconds to complete and has close to 100% repeatability. An efficient, “two‐step” protocol based on the initial use of the CVS test followed by full color assessment in only those who fail the CVS test is also described.

Analysis of Hue Circle Perception of Congenital Red-green Congenital Color Deficiencies Based on Color Vision Model

To investigate individual property of internal color representation of congenital red-green color-deficient observers (CDOs) and color-normal observers (CNOs) precisely, difference scaling experiment using pairs of primary colors was carried out for protans, deutans, and normal trichromats, and the results were analyzed using multi-dimensional Scaling (MDS). MDS configuration of CNOs showed circular shape similar to hue circle, whereas that of CNO showed large individual differences from circular to U- shape. Distortion index, DI, is proposed to express the shape variation of MDS configuration. All color chips were plotted in the color vision space, (L, r/g, y/b), and the MDS using a non-linear conversion from the distance in the color vision space to perceptual difference scaling was successful to obtain U-shape configuration that reflects internal color representation of CDOs.

Testing a Popular Smartphone Application for Colour Vision Assessment in Healthy Volunteer Subjects

ABSTRACT We aimed to compare the Ishihara pseudoisochromatic colour vision test with a colour vision test from a popular smartphone application (EyeHandBook [EHB]) using digital image processing to simulate colour vision deficiencies. Three digital versions of the Ishihara and EHB slides were created: full colour; 32 bit- greyscale (removing all colour information); and blue channel (to simulate red-green colour vision deficiencies). Twenty healthy volunteers were shown each colour-edited plate. The answers they reported were compared with what would be expected for that colour-simulation scenario based on the answer key provided in the Ishihara booklet (“expected” answer). There were nine plates that had comparable patterns between the EHB and Ishihara test. We found no significant difference in the overall proportion of “expected” answers for the full colour (p = .35), 32 bit-greyscale (p = .39) and blue channel (p = .22) conditions. There were significant differences between the proportion of “expected” answers among six individual colour- edited plates (p < .05 for each). Colour vision assessment from the EHB is distinct from comparable Ishihara plates. Clinical scenarios that require serial assessment of colour vision may benefit from using the same modality consistently rather than exchanging between the two tests with the assumption of equivalence. Refinement of digital colour editing techniques beyond 32-bit greyscale and RGB channel splitting is necessary in order to accurately simulate colour vision deficiency.

Analysis of Parvocellular and Magnocellular Visual Pathways in Human Retina.

Two main subcortical pathways serving conscious visual perception are the midget-parvocellular (P), and the parasol-magnocellular (M) pathways. It is generally accepted that the P pathway serves red-green color vision, but the relative contribution of P and M pathways to spatial vision is a long-standing and unresolved issue. Here, we mapped the spatial sampling properties of P and M pathways across the human retina. Data were obtained from immunolabeled vertical sections of six postmortem male and female human donor retinas and imaged using high-resolution microscopy. Cone photoreceptors, OFF-midget bipolar cells (P pathway), OFF-diffuse bipolar (DB) types DB3a and DB3b (M pathway), and ganglion cells were counted along the temporal horizontal meridian, taking foveal spatial distortions (postreceptoral displacements) into account. We found that the density of OFF-midget bipolar and OFF-midget ganglion cells can support one-to-one connections to 1.05-mm (3.6°) eccentricity. One-to-one connections of cones to OFF-midget bipolar cells are present to at least 10-mm (35°) eccentricity. The OFF-midget ganglion cell array acuity is well-matched to photopic spatial acuity measures throughout the central 35°, but the OFF-parasol array acuity is well below photopic spatial acuity, supporting the view that the P pathway underlies high-acuity spatial vision. Outside the fovea, array acuity of both OFF-midget and OFF-DB cells exceeds psychophysical measures of photopic spatial acuity. We conclude that parasol and midget pathway bipolar cells deliver high-acuity spatial signals to the inner plexiform layer, but outside the fovea, this spatial resolution is lost at the level of ganglion cells.SIGNIFICANCE STATEMENT We make accurate maps of the spatial density and distribution of neurons in the human retina to aid in understanding human spatial vision, interpretation of diagnostic tests, and the implementation of therapies for retinal diseases. Here, we map neurons involved with the midget-parvocellular (P pathway) and parasol-magnocellular (M pathway) through human retina. We find that P-type bipolar cells outnumber M-type bipolar cells at all eccentricities. We show that cone photoreceptors and P-type pathway bipolar cells are tightly connected throughout the retina, but that spatial resolution is lost at the level of the ganglion cells. Overall, the results support the view that the P pathway is specialized to serve both high acuity vision and red-green color vision.

Behavioural Issues among Primary Schoolchildren with Colour Vision Deficiency

Introduction: Colour vision deficiencies may raise behavioural changes among children. This study explores the presence of any behavioural issues faced by primary schoolchildren with congenital red-green colour vision deficiency (CRGCVD). Materials and Methods: Male schoolchildren, aged 8-11 years old, from 10 randomly selected schools in Klang Valley were screened using Ishihara plates and Farnsworth D-15 test. Children with CRGCVD (study group) and without CRGCVD (control group) were asked to complete the Strength and Difficulties Questionnaire (SDQ) for children (self-report) while their class teachers completed the SDQ for teachers (teacher- report). Difficulty scores were calculated. The test categorised behaviour into 3 categories based on the difficulty scores into ‘normal’, ‘borderline’ and ‘abnormal’ behaviours. Nonparametric test was used to compare the median of difficulty scores between control group and study group. Spearman correlation was used to determine association between self-report SDQ and teacher-report SDQ. Results: A total of 134 schoolchildren were recruited in this study, of which 44 had CRGCVD and 90 were in the control group. Teacher-reported SDQ for the children were obtained from 134 teachers. No statistically significant differences (p&gt;0.05) were noted between the total SDQ scores of children with and without CRGCVD using self-report SDQ and teacher-report SDQ. The total difficulty scores of self-report SDQ and teacher-report SDQ were poorly but significantly correlated. Teachers rated 9.09% of children with CRGCVD as falling under the ‘abnormal’ category, slightly higher than self-rated of 2.27%. Conclusion: This study found no prominent behavioural issues among schoolchildren with CRGCVD.

Color image evaluation of congenital red-green color deficient and normal color vision observers

How and to what extent the increase of Cab * affects on various subjective evaluations for congenital red-green color deficiency (CVD) and normal color vision (NCV) observers was investigated using scenery, food, and graph images. Results of "Pale vs Deep" evaluation indicate similar tendency for all color vision types in all test images, indicating that CVDs recognize the saturation change of images similar to NCVs using some kind of strategy. Individual differences of the CVDs in the results of other adjective pairs such as "Unnatural vs Natural" are generally larger than those of NCVs. Some color combinations in the graph images are indiscriminable for either protan or deutan, and thus are not recommended to be used.

Frequency of Color Vision Deficiency among Saudi Dental Students: A Cross-Sectional Study.

Objective The current research was conducted to evaluate the frequency of color-vision deficiency among dental students of King Khalid University College of Dentistry, Saudi Arabia. Materials and Methods A cross-sectional study was performed among 203 dental students working as interns at male and female dental clinics of King Khalid University College of Dentistry (KKUCOD), Saudi Arabia. The Ishihara color-vision deficiency (CVD) test with 24 plates was used for diagnosis of the problem. Analysis of the data was done by performing Chi-square tests using SPSS software version 20. Results The frequency of total CVD was found to be 3.9%. While the association of gender with total CVD was observed to be statistically nonsignificant, a statistically significant relation was drawn with red-green color deficiency. Out of the total of 203 patients, 44 males were identified with red-green color deficiency, whereas only three females were found to have this condition, therefore revealing that CVD is more prevalent in males. Age was found to have a significant association with red-green color vision deficiency, protanopia, and total CVD. Conclusion A total of 20.19% male dental students had red-green color vision deficiency compared to 1.4% in female students. The dental students must be aware of their congenital color vision deficiency and its impact on their professional life. Screening of such dental students and professionals is quite important so that they can tackle the color vision problems well without having detrimental effect on their future dental practice.

Effect of Membrane Removal on the Production of Calcium Oxide from Eggshells via Calcination

In the pursuit of a circular economy and against a background of viable alternative uses of avian eggshells and eggshell membranes, this research investigated the effect of domesticated chicken eggshell membrane separation on the calcination process and quality of Calcium Oxide (CaO) produced. Acetic acid was used to leach the eggshells for 60 min to aid separation of the shell membrane. X-ray diffraction, red green blue colour model, and thermogravimetric analyses were used to characterize the calcined shells. Leached and separated shells produced CaO of comparable quality and crystallinity to unseparated shells after calcination. Results showed that while leaching and membrane separation did not affect calcination temperature, residual ash from the membrane left impurities in the unseparated shells after calcination. It was concluded that leaching and separating the membranes from eggshells prior to calcination serves to upcycle eggshells by facilitating improved CaO production and membrane value extraction.

Transfer of incompatible spatial mapping to the vertical Simon task generalizes across effectors but not stimulus features.

For the vertical Simon task, in which stimuli and responses are arrayed along the vertical dimension and stimulus location is irrelevant, a Simon effect (benefit for stimulus-response correspondence) is typically obtained. Results have been mixed about whether performing fewer than 100 trials of a spatially incompatible mapping prior to a Simon task reduces or eliminates this vertical Simon effect in a transfer session. Several reasons have been suggested to explain why previous studies show disparate results. Previously, we ruled out orientation of the response panel in the transverse or horizontal plane as a critical factor. The present experiments evaluated two other possible factors: finger/hand placement and relevant stimulus dimension. In Experiment 1, we found reduction of the vertical Simon effect for a circle-square discrimination after incompatible practice using a separate numeric keypad as the response device, regardless of whether the keypad was placed on a table and operated by index fingers or held in the hands and operated by thumbs. In Experiment 2, we replicated the reduction for the circle-square discrimination but found no evidence of reduction for a red-green color discrimination. Overall, our results suggest that the relevant discrimination of red-green color versus circle-square shape is responsible for the discrepancy in results across prior studies.

Water bucket colour preferences in horses

There is a general agreement that horses have dichromatic colour vision with similar capabilities to those of human beings with red-green colour deficiencies. However, whether colour perception has an impact on equine preference for drinking water and how pronounced the colour stimulus might be for horses is still unknown. This study aimed to investigate the preference of horses for different coloured buckets (red, light green, yellow, green, light blue, turquoise) with different tones, in terms of lightness and darkness, measured by the amount of water consumed from each of them in an outdoor arena. Three Thoroughbred and 3 Haflinger horses were used in the study, and data were collected between 09:00 - 16:00 h. The results showed that the average water consumption during this period can reach up to 25.74 L (at an average environmental temperature of 27.35 °C), and significantly more water had been consumed from the turquoise-coloured bucket than from the other colours. It was also observed that the light toned colours (turquoise, light blue) were preferred to dark ones (green, yellow, red). It is suggested to use water buckets that are turquoise and light blue. Further studies are needed to better understand the relationship between water consumption and colour vision.

Performance Improvement of a Deep Learning-based Object Recognition using Imitated Red-green Color Blindness of Camouflaged Soldier Images

The camouflage pattern was difficult to distinguish from the surrounding background, so it was difficult to classify the object and the background image when the color image is used as the training data of deep-learning. In this paper, we proposed a red-green color blindness image transformation method using the principle that people of red-green blindness distinguish green color better than ordinary people. Experimental results show that the camouflage soldier's recognition performance improved by proposed a deep learning model of the ensemble technique using the imitated red-green-blind image data and the original color image data. Keywords: Deep Learning(심층 ì‹ ê²½ë§í•™ìŠµ), Camouflaged Soldier Recognition(위장군인인식), Ensemble Learning(앙상블 학습), Red-green Color Blindness(ì ë¡ìƒ‰ë§¹)

Cone mosaic characteristics in red-green colour deficiency: a comparative study

ObjectiveTo compare photoreceptor cone characteristics using adaptive optics (AO) technology between congenital colour blind patients and healthy age-matched controls. DesignCross-sectional. Participants21 eyes (21 cases) with congenital red-green colour blindness and 21 eyes of age-matched controls (21 controls), all having a best-corrected visual acuity of 20/20 and normal ophthalmological examination, were recruited. MethodsColour vision testing was done using the Farnsworth–Munsell 100-Hue test and Nagel anomaloscope. Imaging of fovea was done using rtx1 AO retinal camera with a sampling window size of 4° × 4°. Peak cone density, intercone spacing, cone regularity, and cone dispersion were determined using AOdetect Mosaic software. ResultsOverall, mean cone characteristics at 2° off fixation in cases and controls, respectively, were density 26 587 ± 1328/26 448 ± 687 cells/mm2 (p = 0.67), spacing 6.69 ± 0.17/6.75 ± 0.11 μm (p = 0.19), regularity 94.36 ± 2.56/94.83 ± 1.28% (p = 0.46), dispersion 10.22 ± 1.21/11.68 ± 0.79% (p = 0.0001), and hexagonality 50.62 ± 4.21/49.52 ± 2.45% (p = 0.31). No significant difference was noted in various cone metrics except dispersion, which was markedly decreased in colour-deficient individuals. At 4° off fixation, the cone characteristics were not significantly different between cases and controls: density 16 521 ± 1230/16 930 ± 678 cells/mm2 (p = 0.37), spacing 8.60 ± 0.29/8.46 ± 0.17 μm (p = 0.19), regularity 92.68 ± 2.83/92.6 ± 3.05% (p = 0.95), dispersion 13.43 ± 3.48/13.65 ± 2.38% (p = 0.87), and hexagonality 45.22 ± 3.8/45.21 ± 5.5% (p = 0.99). A significant reduction in cone density, regularity, and hexagonality was associated with corresponding increase in spacing and dispersion as we moved from 2° to 4° off fixation in both cases and controls. ConclusionCone photoreceptor characteristics are anatomically well preserved in young colour-deficient individuals except cone dispersion.

Flexible, Large‐Area Covert Polarization Display Based on Ultrathin Lossy Nanocolumns on a Metal Film

AbstractCovert polarization displays provide a barrier to the inadvertent viewing of stored optical information. For security and anti‐counterfeiting purposes, access to concealed information without compromising packaging aesthetics is required in certain situations. However, optical conversion with polarized light typically requires sophisticated nanostructures only possible with limited materials, which are not appropriate for application to objects requiring flexibility or conformability, and color selectivity. A flexible, large‐area covert polarization display based on ultrathin lossy nanocolumns with wide color selectivity is presented. Self‐aligned porous nanocolumns (PNCs) fabricated by glancing angle deposition are a facile approach to polarization distinguishable structures. PNCs deposited on metal are designed to switch color in accordance with polarization by ultrathin resonance, which is modeled using the complex effective refractive index. Several combinations of material and thickness are presented to extend color selectivity with the standard red green blue gamut and color palette. As a demonstration, covert polarization display labels are attached to daily objects with curved and wrinkled surfaces, and hidden quick response codes are revealed by polarization adjustment in indoor and outdoor environments. Moreover, a multifunctional water contact detection covert polarization display is demonstrated based on the sensitivity of PNCs to the refractive index of the analyte.

Evaluation of Central Macula, Retinal Nerve Fiber Layer, and Ganglion Cell Complex Thickness in Congenital Color Vision Deficiency.

Objectives:This study was designed to evaluate the thickness of the central macula, the retinal nerve fiber layer (RNFL), and the ganglion cell complex (GCC) in individuals with congenital red-green color vision deficiency (CVD) using spectral-domain optical coherence tomography (SD-OCT).Methods:This study included 22 males with a red-green CVD (Group 1) and 22 males with normal color vision (Group 2). The Ishihara test was used to determine CVD. SD-OCT was used to evaluate the central macula, RNFL, and GCC measurements of all of the study participants. The quantitative data of the 2 groups were compared. The Kruskal-Wallis test was used for the statistical analysis and a p value <0.05 was considered significant.Results:The mean central macula thickness observed in Group 1 and 2 was 255.00±25.50 µm and 248.95±24.70 µm, respectively. The mean RNFL thickness of Group 1 and 2 was 110.66±14.70 µm and 109.49±9.90 µm, respectively, and the mean GCC thickness of Group 1 and 2 was 97.70±10.80 µm and 97.56±5.10 µm, respectively. There were no significant differences between the groups in the assessment of the central macula, RNFL, or GCC thickness (p=0.20, p=0.34, p=0.37).Conclusion:The results of this study suggested that congenital red-green CVD does not affect the thickness of the central macula, RNFL, or GCC. To the best of our knowledge, this is the first study to evaluate the thickness of the GCC in individuals with congenital red-green CVD.

Türk Çocuklarında Renkli Görme Bozukluklarının Sıklık ve Ağırlığının Değerlendirilmesi

Objective: To determine the prevalence of color vision deficiency, ratio of deutan/protan and the distribution of the severity of color vision deficiency among Turkish children and to evaluate the usability the Color Assessment and Diagnosis (CAD) test in children. Material and Methods: A total of 1374 children (627 girls and 747 boys) of age 6-16 years were included in this study. The first 15 plates of the Ishihara test were used to evaluate to screen for color deficiency. Those who made three or more errors had their color vision examined using the CAD test to determine the type and severity of color vision deficiency. The prevalence of color vision deficiency in boys and girls, ratio of deutan and protan deficieny and the distribution of the severity of loss were calculated. The correlations of the CAD test result and number of mistakes on the Ishihara test with age were also evaluated. Results: Thirty seven boys (4.95%) and 3 girls (0.47%) made 3 or more errors and were categorized as having color vision deficiency. In total, 32 subjects completed the CAD test, 22 subjects (68.7%) were classified as deutan and 10 (31.2%) as protan with the ratio of 2.2:1. In terms of the CAD based color vision grading system for red-green deficiency 3 subjects (9.3%) were classed as color vision (CV) category 3, 5 subjects (15.6%) as CV category 4 and 24 subjects (75%) as CV category 5. There was no significant correlation between the CAD test result and number of mistakes on the Ishihara test with age (r=-0.075, p=0.684 and r=-0.191, p=0.295 respectively). Conclusion: The results reveal severe loss of red-green color vision in 75% of the children with color vision deficiency. The study also demonstrates that the CAD test can be used in children as young as six years.

Analysis of colorimetric parameters of international commission on illumination L*a*b* system in the color of maxillary central incisors

Introduction. Tooth color can be represented in a three-dimensional color system by applying L* (lightness), a* (red-green color tone) and b* (yellow-blue color tone) coordinates. Clinically significant color difference, Delta-E, can be expressed in units that are correlated with visual perception using the International Commission on Illumination L*a*b* system. The aim of the study was spectrophotometric analysis of the natural maxillary central incisor color, and to establish any gender-related differences in lightness, red-green tone, and yellow-blue tone coordinates. Material and Methods. The study included 80 students (40 male and 40 female, with an average age of 22 years). The color of the maxillary right central incisor was determined using an intraoral spectrophotometer and VITAPAN Classical and VITA 3D-Master color shade guides. Lightness, red-green tone, and yellow-blue tone values were recorded for each result. The obtained data were processed by using ?2, Student?s t-test and Mann-Whitney test. Results. Results showed no statistically significant gender-related difference in color according to the VITApan Classical and VITA 3D-Master color key. No difference was found in the lightness of the central maxillary incisor between genders, or in terms of red-green tone (p = 0.860573). A statistically significant difference was found when observing the sex-related yellow-blue tone of the color of the central maxillary incisor. Conclusion. The analysis of colorimetric parameters of the International Commission on Illumination L*a*b* system provides useful information about the tooth color in the examined population, while potentially revealing differences in lightness, red-green tone and yellow-blue tone between genders.