Aesthetic Dentistry - What You Decided and What I Want: Shade Selection

ABSTRACT Objective: To assess the relationship between patients' and dentists' perceptions of shade selection and its impact on satisfaction with the prosthesis. Material and Methods: A single group pre-post study was conducted at the Prosthodontics department of a teaching hospital in India. One hundred ten participants were selected through a systematic random sampling technique with inclusion and exclusion criteria. Patients' attitudes regarding the aesthetics of their maxillary anterior teeth were recorded using a validated questionnaire. Shades for the intended prosthetic crown selected by the dentist and chosen by the patient were recorded separately, and patient satisfaction with the appearance of the final prosthesis was recorded. We used descriptive statistics followed by Pearson's Chi-square test and a binomial logistic regression model for inferential statistics. Results: 109 participant's data were available for final analysis. Patients choose lighter shades than the dentist's selection, which is statistically significant (p=0.000). 73.4% were satisfied with the final prosthesis, and the binomial logistic regression model identified using patient-selected shade for the final prosthesis was significantly associated with patients' satisfaction with the final prosthesis (OR=3.3, p=0.001). Conclusion: The patient's preference should be considered with the dentist's option when selecting a shade to create good esthetics.

Parámetros para la evaluación visual e instrumental del color dental en estudios in-vitro. Revisión de la literatura / Parameters for visual and instrumental assessment of tooth colour in in-vitro studies. Literature review

Objetivo: establecer los parámetros para la evaluación visual e instrumental del color dental en estudios in-vitro a partir de la literatura científca publicada entre 2015 y 2021. Métodos: se realizó la búsqueda en las bases de datos: PubMed, Web of Science, Science Direct, Scopus, Scielo y Lilacs; también en el motor de búsqueda Google Académico y las bibliotecas de las editoriales Wiley y Springer. Las palabras clave utilizadas fueron tooth, color, in-vitro, color perception, shade matching, thresholds, appearance, surrounding, "CIELAB" y "CIEDE2000". Teniendo en cuenta los criterios de elegibilidad, se seleccionaron los estudios de acuerdo al título, resumen y texto completo. Resultados: la búsqueda arrojó un total de 37 publicaciones que se agruparon en tres tópicos: 1. toma de color visual: condiciones ambientales, observadores y nivelación; 2. toma de color instrumental: instrumentos; y 3. procesamiento de datos: cálculo de la diferencia de color y umbrales de perceptibilidad (PT) y aceptabilidad (AT). Conclusiones: los aspectos más importantes en la evaluación visual son la iluminación, el ambiente para registro (sitio, entorno y fondo alrededor de la muestra), las condiciones geométricas de visualización, los observadores y el uso de guías. En la evaluación instrumental es relevante elegir el aparato apropiado de acuerdo con su precisión y reproducibilidad, como los espectroradiómetros y los espectrofotómetros de uso clínico. Se presenta el procesamiento de datos para establecer las variaciones de cada coordenada, las diferencias de color (ΔE): CIELAB y CIEDE2000, los umbrales y los lineamientos.

Objective: To establish the parameters for the visual and instrumental evaluation of tooth color in in-vitro studies based on the scientifc literature published between 2015 and 2021. Methods: The search was carried out in the databases of PubMed, Web of Science, Science Direct, Scopus, Scielo, Lilacs; search engine Google Scholar and publishers' library of Wiley and Scielo, using the keywords "tooth", "color", "in vitro", "color perception", "shade matching", "thresholds", "appearance", "surrounding", "CIELAB", and "CIEDE2000". The literature was selected according to the title, abstract and full text taking into the eligibility criteria. Results: It yielded a total of 37 publications, which were grouped into three topics: 1. visual color acquisition: environmental conditions for color acquisition, observers and levelling. 2. instrumental color sampling: instruments. 3. Data processing: Calculation of color diference and perception thresholds (PT) and acceptability thresholds (AT). Conclusions: The most important aspects in the visual assessment are lighting, the environment for color registration (site, environment and background around the sample), the geometric conditions of visualization, the observers and the use of guides. Regarding the instrumental assessment of color, the appropriate devices must be chosen according to its precision and reproducibility, being the spectrophotometers and spectroradiometers the most precise ones. It is presented how the data processing is carried out to establish the variations of each coordinate, the color diferences (ΔE): CIELAB and CIEDE2000, thresholds and guidelines.

Valoración del grado de pigmentación en dientes acrílicos sometidos a humo del cigarrillo / Assessment of the degree of pigmentation in acrylic teeth subjected to cigarette smoke

INTRODUCCIÓN. Los cambios de color en los dientes acrílicos dependen de varios factores, con el humo de cigarrillo como uno de los principales agentes de igmentación de las prótesis. OBJETIVO. Valorar el grado de pigmentación en dientes acrílicos sometidos al humo del cigarrillo, mediante espectrofotometría digital. MATERIALES Y MÉTODOS. Estudio observacional, analítico, de caso y control. Muestra de 60 dientes acrílicos divididos en dos grupos: A (resina acrílica de 3 capas) y B (resina acrílica de 4 capas). Se subdividió en: grupo 1: dientes sometidos a humo de cigarrillo estándar con filtro de carbón; grupo 2: dientes sometidos a humo de cigarrillo estándar sin filtro; y, grupo 3: grupo control. Cada uno de éstos se expuso a 150 cigarrillos, 5 diarios durante 30 días y el grupo control fue mantenido a 37ºC en saliva artificial durante 30 días sin aplicación de humo de cigarrillo. Para la toma de color se empleó espectrofotómetro Vita Easyshade®. Los análisis se realizaron en el programa estadístico International Business Machines Statistical Package for the Social Sciences mediante la prueba de Kruskal-Wallis y comparaciones de Dunn. RESULTADOS. Se determinó que la pigmentación del grupo B fue mayor a la del grupo A, con una diferencia significativa entre ellos (p< 0,05). No se encontró datos estadísticamente significativos entre cigarrillos (con filtro - sin filtro). CONCLUSIÓN. La exposición al humo de cigarrillo pigmentó los dientes acrílicos de ambas propiedades siendo mayor en los dientes de resina acrílica de 4 capas.

INTRODUCTION. Color changes in acrylic teeth depend on several factors, with cigarette smoke as one of the main agents of denture pigmentation. OBJECTIVE. To assess the degree of pigmentation in acrylic teeth subjected to cigarette smoke, using digital spectrophotometry. MATERIALS AND METHODS. Observational, analytical, case-control study. Sample of 60 acrylic teeth divided into two groups: A (3-layer acrylic resin) and B (4-layer acrylic resin). It was subdivided into: group 1: teeth subjected to standard cigarette smoke with charcoal filter; group 2: teeth subjected to standard cigarette smoke without filter; and, group 3: control group. Each of these was exposed to 150 cigarettes, 5 daily for 30 days and the control group was maintained at 37ºC in artificial saliva for 30 days without application of cigarette smoke. Vita Easyshade® spectrophotometer was used for color determination. The analyses were performed in the statistical program International Business Machines Statistical Package for the Social Sciences using the Kruskal-Wallis test and Dunn's comparisons. RESULTS. It was determined that the pigmentation of group B was greater than that of group A, with a significant difference between them (p< 0,05). No statistically significant data was found between cigarettes (filtered - unfiltered). CONCLUSION. Cigarette smoke exposure pigmented acrylic teeth of both properties being higher in 4-layer acrylic resin teeth.

Variaciones histórico-culturales de la estética dental / Historical and cultural variations of teeth aesthetics

Resumen La estética dentaria es un tema de amplia relevancia en la odontología actual, tanto en el ambiente universitario como en la práctica privada. Cuando las personas expresan que desean una sonrisa más hermosa, dentistas y pacientes piensan automáticamente en aclarar el color de los dientes como un componente importante de este proceso. ¿Cuál es la razón de esta concordancia tácita? Algunos podrían argüir que una sonrisa saludable es naturalmente más blanca, pero sabemos que la funcionalidad fisiológica no necesariamente está asociada a una estética socialmente determinada. Es más, muchas veces los procedimientos estéticos implican modificaciones corporales que no necesariamente son naturales, ni saludables. El objetivo de esta revisión, es brindar elementos de discusión acerca de aspectos históricos y culturales relacionados con el posicionamiento del color dentario como parte importante de un ideal estético. Se pretende argumentar, que el deseo de tener dientes más blancos reside eminentemente en influencias culturales. Asimismo, se invita a la reflexión de que, si los "dientes blancos" debiesen ser equiparados a "dientes saludables", con las consecuentes ramificaciones que implicaría esta suposición, en nuestro mundo profesional.

Abstract Dental aesthetics is a topic of wide relevance in current dentistry, both in dental education and in private practice. When people express that they want a beautiful smile, both dentists and patients think of whitening tooth color. What is the reason for this tacit agreement? Some might argue that a healthy smile is naturally whiter, but we know that physiological functionality is not always associated with socially determined aesthetics. Furthermore, some aesthetics procedures might involve body modifications that are not necessarily natural nor healthy. The aim of this review is to to provide elements of discussion about historical and cultural aspects related to the positioning of tooth color as an important part of an aesthetic ideal. To argue that the desire for whiter teeth resides in cultural influences. To invite reflection if "white teeth" should be equated with "healthy teeth", with the consequences this assumption would imply in our professional field.

Visual processing of color and shape in people with leprosy

Abstract The aim of this study was to analyze the contrast sensitivity of spatial luminance and the color discrimination thresholds of the protan, deutan, and tritan axes of people with leprosy. This study included 8 subjects with leprosy (M = 4, W = 4, M = 33.38 ± 8.7) and 8 healthy subjects (M = 4, W = 4, M = 30.89 ± 5.8). The contrast sensitivity was evaluated by the Metropsis software version 11.0 with vertical sinusoidal grids of frequencies of 0.2, 0.5, 1, 5, 10, and 16 cycles per degree of visual angle (cpd) and color vision by the desaturated Lanthony D15 tests and the trivector and ellipse protocols of the Cambridge Color Test. The results showed significant differences between the groups in the processing of spatial frequencies of 0.2 (U = 14; p = .018); 5.0 (U = 45.0; p = .001); 10.0 (U = 45.0; p = .001), and 16.0 (U = 45.0; p = .001) cpd. The difference in color recognition through D15d (U = 4.0; p = .002). Ellipse 2 (U = 10.0; p = .012) and ellipse 3 (U = 9.0; p = .009) were discriminated against. Overall, the results indicate that leprosy changes the visual processing of low, medium, and high spatial frequencies, as well as the sensitivity of the short wavelength (tritan line of confusion) and long (protan line of confusion) cones.

Catarata e a expressao cromática na obra de Monet / Cataract and chromatic expression in Monet's work

Resumo Por conta de uma doença ocular, a obra de Monet foi analisada por múltiplas facetas, incluindo o reflexo da deterioração de sua visão nos seus trabalhos, motivo deste trabalho de revisão. Tendo como referência este panorama, propõe-se aqui pensar, por meio de algumas obras marcantes da biografia de Monet, a doença ocular catarata e o seu papel na história de vida deste pintor.

Abstract Due to the ocular disease, Monet's work was analyzed by multiple facets, including the reflection of the deterioration of his vision in his works, reason for this work of revision. With reference to this panorama, it is proposed here to think, by means of some remarkable works of the biography of Monet, the ocular cataract disease and the paper of this in the history of this painter's life.

Evaluation of the color vision acuity pattern of undergraduates of health courses in a Brazilian university / Avaliação do padrão de acuidade visual para cores de acadêmicos da área de saúde em Universidade brasileira

ABSTRACT Objective: The goal of the study is to analyze the color vision acuity pattern in undergraduates of health courses and to discuss the impact of these diseases in this population. Color deficiencies interfere significantly in the daily routine of professionals in the health area who need to discern different color hues in several situations of their everyday practice. Methods: Sixty-four volunteers, undergraduates of health courses of the Federal University of Alfenas (UNIFAL-MG), participated in the study. One man was excluded because he did not fit the inclusion criteria. Two groups were analyzed according to sex with the Farnsworth Munsell 100-Hue test. Results: There were no significant differences between the eyes and between the groups analyzed. The color vision acuity pattern is between 35 and 40, according to the Total Error Score. The gender issue does not influence the general pattern of the color vision acuity of the health courses undergraduates when those with color vision disorders are removed. Conclusion: Screenings and guidance should be given to undergraduates of health courses so that, aware of their condition of presenting some type of color disorder, they shall make the appropriate decision on which career to follow so that such limitation does not interfere with the quality of their daily life.

RESUMO Objetivo: O objetivo do estudo é analisar a acuidade visual média para cores de estudantes da área de saúde e discutir o impacto das doenças que a afetam nessa população. Deficiências cromáticas interferem de forma significativa no dia a dia de profissionais da área da saúde que necessitam de discernir diferentes matizes em diversas situações de sua prática profissional. Métodos: Participaram da pesquisa 64 voluntários, estudantes de cursos da área de saúde da Universidade Federal de Alfenas, sendo que 1 homem foi excluído por não se adequar aos critérios de inclusão. Dois grupos foram analisados, de acordo com o sexo, com o teste de Farnsworth Munsell 100-Hue. Resultados: Não houve diferenças significativas entre os olhos e entre os grupos analisados. O padrão de visão de cores encontra-se entre 35 e 40, de acordo com a Pontuação do Erro Total. A questão de gênero não influencia no padrão geral da qualidade de visão de cores de estudantes da área de saúde, quando retirados aqueles que apresentam distúrbios da visão cromática. Conclusão: Devem ser realizadas triagens e orientação para estudantes de cursos da área de saúde para que, cientes da sua condição de apresentar algum tipo de distúrbio cromático, possam tomar a decisão adequada sobre qual carreira seguir para que tal limitação não interfira na qualidade de sua vida diária.

The effect of high altitude on human color perception / 生理学报

Exposure to a high altitude hypoxia environment has significant negative effects on human central nervous system. Many previous studies have explored the influence of the high altitude environment on human color perception in a simulated high altitude environment or in an environment acutely exposed to high altitude, but little has been done in migrators and natives exposed to high altitude and low oxygen for a long period of time. In this study, the minimal-change method was used to examine whether the color perception of red, green, blue and yellow was affected by the high altitude in 30 plain residents, 30 Han migrators who have lived in the high altitude for 2 years, and 28 high-altitude-adapted Tibetan natives. The results showed that long-term high altitude exposure had the most significant effect on the blue and red color perception in the natives and the migrators, with the effect on the blue color being significantly greater than that on the red color. However, the effects on green color processing only happened to the natives. The results suggest that there is an internal correlation between blood supply and selectivity changes of visual color processing caused by exposure to the plateau environment.

Preliminary data for performance in hue ordering tests during pregnancy

The visual system of women changes during pregnancy. Few reports have addressed the effects of pregnancy on color vision. We aimed to compare the color vision of women in the first, second, and third trimesters of pregnancy. Fifty women were divided into first (n=10), second (n=10), third trimester pregnancy groups (n=10), and non-pregnant group (n=20). We used the Farnsworth D15 and Lanthony desaturated D15 (D15d) tests. The hue ordering quantified the amount of error (C-index) and the chromatic selectivity of the errors (S-index). Bland-Altman analysis was applied to the hue ordering data. No difference was found for Farnsworth D15 test results obtained from the pregnant groups and the non-pregnant group (P<0.0083). For the Lanthony D15 desaturated test, the third trimester pregnant group had higher C-index and S-index than non-pregnant women and first-trimester pregnant women (P<0.0083). The Bland-Altman analysis showed that the limits of agreement increased as pregnancy advanced, and the errors were biased to the D15d test. In this study, color vision was impaired during pregnancy. Color vision evaluation could be used as an indicator of the functional status of the central vision during pregnancy.

The impact of at home and in-office bleaching agents on the color stability of bulk-fill composite resins / Impacto de agentes clareadores caseiros e de consultório na estabilidade de cor de resinas compostas bulk fill

Objective: This study compared different composites for color stability after exposure to at home and in-office bleaching gels. Material and Methods: Composite resin specimens (6mm diameterx2mm thickness) were manufactured according to the following groups (n=20): RC- Conventional; BF-Bulk Fill; RF-Flow; BFF-Bulk-Fill Flow. The surfaces were stained with coffee solution for 36h. A spectrophotometer was used to record the initial color (L*a*b*). Half of the specimens from each group underwent bleaching with 35% hydrogen peroxide (in-office) in three 45-minute applications. New color measurements were performed after 7, 14 and 21 days. The other half of the specimens underwent bleaching with 22% carbamide peroxide (at home) in 14 1-hour applications. Further color measurements were performed after 7 and 14 days. For comparison between the color coordinates in different periods, ANOVA for repeated measures was applied (α=5%). The color variation (ΔE) was calculated for each group. Results: For in-office bleaching, there were no significant differences between the periods b* coordinate of the RF group, and for L* and b* coordinates of the BFF group. For at home bleaching the groups BF and BFF showed no differences for the L* coordinate. For the other coordinates, there was difference between the initial periods and after 14 days. The ΔE variation presented higher values for the at home bleaching groups. For both whiteners the bulk-fill resins presented the greatest color variations. Conclusions: Bulk Fill resins do not guarantee greater color stability than the other composite resins tested, including conventional flow resin. The conventional composite resin showed the lower ΔE. (AU)

Objetivo: Esse estudo comparou diferentes resinas compostas quanto a estabilidade de cor após exposição a géis clareadores de uso caseiro e de consultório. Material e Métodos: Espécimes de resina composta (6mm diâmetro x 2mm espessura) foram confeccionados de acordo com os seguintes grupos (n=20): RC- Convencional; BFBulk Fill; RF-Flow; BFF-Bulk-Fill Flow. As superfícies foram manchadas com solução de café por 36 horas. Um espectrofotômetro foi utilizado para mensurar a cor inicial (L*a*b*). Metade dos espécimes de cada grupo foi submetida ao clareamento com peróxido de hidrogênio 35% (clareamento de consultório) durante três aplicações de 45 minutos. Novas mensurações de cor foram realizadas após as aplicações de 7, 14 e 21 dias. A outra metade dos espécimes foi submetida ao clareamento com peróxido de carbamida 22% (clareamento caseiro) em 14 aplicações de 1 hora durante 14 dias. Novas mensurações de cor foram realizadas após 7 e 14 dias. Para comparação entre as coordenadas nos diferentes períodos foi aplicada a análise de variância ANOVA para medidas repetidas (α=5%). A variação de cor (ΔE) foi calculada para cada grupo. Resultados: Para o clareamento de consultório não houve diferenças significativas para a coordenada b* do grupo RF, e para L* e b* no grupo BFF. Para o clareamento caseiro os grupos BF e BFF não apresentaram diferenças para a coordenada L*. Para as outras coordenadas, houve diferenças entre os períodos inicial e após 14 dias. A variação de ΔE apresentou maiores valores para o grupo submetido ao clareamento caseiro. Para ambos clareadores a resina composta bulk fill apresentou as maiores variações de cor. Conclusões: As resinas compostas bulk fill não garantiram uma maior estabilidade de cor quando comparadas as resinas compostas tradicionais testadas, incluindo a resina flow. A resina composta convencional apresentou a menor variação de ΔE. (AU)

Psicofísica visual em caso de toxoplasmose ocular congênita / Visual psychophysics of congenital ocular toxoplasmosis case

Resumo A toxoplasmose ocular congênita é uma manifestação da infecção pelo parasita Toxoplasma gondii que ocorrer por meio placentário. Essa doença pode provocar importantes sequelas visuais. Este trabalho descreve um estudo de caso que utilizou avaliação psicofísica visual para descrever alterações funcionais decorrentes da toxoplasmose ocular congênita. A avaliação foi realizada em paciente de 30 anos, sexo masculino, residente em São Luís (MA), hígido com histórico da mãe ter apresentado infecção por toxoplasmose no período gestacional. Somente aos 26 anos foi feita uma avaliação médica detalhada que descreveu lesão na fóvea do olho direito. Na avaliação clínica clássica e na avaliação psicofísica visual, o paciente apresentou visão normal para o olho esquerdo. O olho direito apresentou baixa acuidade visual (valor decimal: 0,028), campo visual com escotomas localizados até 20º de ângulo visual e alteração da visão de cor. O estudo fornece informações médicas seguras e relevantes para o diagnóstico de toxoplasmose ocular congênita utilizando testes eficazes, de baixo custo e boa portabilidade, possibilitando uma alternativa de diagnóstico funcional para ser aplicada em locais de difícil acesso pelo interior do Brasil.

Abstract Congenital ocular toxoplasmosis is a manifestation of infection by the parasite Toxoplasma gondii that occurs through the placenta. This disease can lead to important visual sequelae. This paper describes a case report that uses visual psychophysics for the alterations of congenital ocular toxoplasmosis. The evaluation was performed in a 30-year-old man, a resident of São Luís (MA), with a history of his mother have had toxoplasmosis in the gestational period. Only at 26 years-old he did the detailed medical evaluation that described a lesion the fovea of the right eye. In the classic clinical examination and in visual psychophysical evaluation, the patient presented normal vision for the left eye. The right eye had low visual acuity (decimal value: 0.028), visual field with scotomas up to 20º of visual angle and alteration of color vision. The study offers safe and relevant medical information for the diagnosis of congenital ocular toxoplasmosis using a low-cost evaluation and with good portability, allowing a functional diagnostic alternative to be applied in places difficult to access in the interior of Brazil.

Cor e qualidade formal no método de Rorschach em um grupo de crianças de 11/12 anos de idade / Color and form quality in the Rorschach method in a group of 11/12 year-old children / Color y calidad formal en el Rorschach de un grupo de niños de 11/12 años

Com os resultados de alguns estudos normativos do método de Rorschach, verificou-se que os cartões ditos vermelhos, II e III, e dois dos três cartões ditos coloridos, VIII e X, suscitam a frequência mais elevada de respostas com fraca qualidade formal, levantando-se a hipótese de que a cor poderia ser responsável por tal ocorrência. Mediante o uso da versão padronizada e da versão acromática dos cartões II, III, VIII, IX e X, aplicadas a uma amostra de 80 crianças portuguesas de ambos os sexos, com idades entre 11 e 12 anos, constatou-se que apenas no cartão III se encontram indicadores irrecusáveis de que a cor vermelha está associada à frequência mais elevada de respostas de fraca qualidade formal nesse cartão. Adicionalmente, identificou-se que no cartão X a cor contribui para maior frequência de respostas de boa qualidade formal.(AU)

Results from some Rorschach normative studies revealed that the said red cards II and two of the three said colored cards VIII and X elicit the highest frequency of poor form quality responses. This fact permitted the formulation of a hypothesis that color could be the cause of such an occurrence. Administration of a standardized and achromatic version of cards II, III, VIII, IX, and X to a sample of 80 Portuguese students of both sexes and aged 11 to 12 years old revealed that only with card III there is strong evidence that the color red is associated with the high frequency of poor form responses. Additionally, results showed that the color is responsible for a higher frequency of good form responses on card X.(AU)

A partir de los resultados obtenidos con algunos estudios normativos del Rorschach, se ha verificado que las láminas rojas, II y III, y las dos láminas coloridas VIII y X se cuentan entre las cinco que proporcionan mayor frecuencia de respuestas con forma distorsionada. Este dato nos ha inducido a levantar la hipótesis de que el color podría ser la causa de la presencia acentuada de tales respuestas. La aplicación de la versión estándar y de la versión acromática de las láminas II, III, VIII, IX y X a una muestra de 80 niños portugueses, de ambos géneros y 11/12 años de edad, permitió verificar la presencia de fuertes indicadores de que el color rojo, en la lámina III, es la causa de la elevada frecuencia de formas distorsionadas allí ocurridas. Adicionalmente, cumple señalar que, en la lámina X, el color contribuye para el aumento de la frecuencia de respuestas de buena calidad formal.(AU)

Comparison of the optical properties of pre-colored dental monolithic zirconia ceramics sintered in a conventional furnace versus a microwave oven

PURPOSE: The purpose of this study was to compare the optical properties of pre-colored dental monolithic zirconia ceramics of various thicknesses sintered in a microwave and those in a conventional furnace. MATERIALS AND METHODS: A2-shade of pre-colored monolithic zirconia ceramic specimens (22.0 mm × 22.0 mm) in 3 thickness groups of 0.5, 1.0, and 1.5 mm were divided into 2 subgroups according to the sintering methods (n=9): microwave and conventional sintering. A spectrophotometer was used to obtain CIELab color coordinates, and translucency parameters and CIEDE2000 color differences (ΔE 00) were measured. The relative amount of monoclinic phase (X(m)) was estimated with x-ray diffraction. The surface topography was analyzed by atomic force microscope and scanning electron microscope. Statistical analyses were conducted with two-way ANOVA (α=.05). RESULTS: There were small interaction effects on CIE L*, a*, and TP between sintering method and thickness (P<.001): L* (partial eta squared η(p)²=0.115), a* (η(p)²=0.136), and TP (η(p)²=0.206), although higher b* values were noted for microwave sintering regardless of thickness. Color differences between two sintering methods ranged from 0.52 to 0.96 ΔE(00) units. The X(m) values ranged from 7.03% to 9.89% for conventional sintering, and from 7.31% to 9.17% for microwave sintering. The microwave-sintered specimen demonstrated a smoother surface and a more uniform grain structure compared to the conventionally-sintered specimen. CONCLUSION: With reduced processing time, microwave-sintered pre-colored dental monolithic zirconia ceramics can exhibit similar color perception and translucency to those by conventional sintering.

Selección de color dentario: comparación de los métodos visual y espectrofotométrico / Selection of tooth colour: comparison of visual and spectrophotometric methods

Introducción En odontología la selección de color se realiza mediante métodos visuales o instrumentales: el primero, ampliamente utilizado, es subjetivo e influenciado por diversos factores, en tanto el instrumental con espectrofotómetro es objetivo y simple, pero poco utilizado. Objetivo Comparar los resultados en la selección del color utilizando los métodos visual y el espectrofotómetro Easyshade Compact, para verificar si existen diferencias. Material y método Cincuenta odontólogos, 25 hombres y 25 mujeres, seleccionaron el color de una pieza dentaria anterior sana con el muestrario Vitapan 3D Master, y se compararon los resultados con los obtenidos al utilizar el espectrofotómetro. Los datos se analizaron mediante Chi-cuadrado. Resultados El 18% de los odontólogos (el 24% de las mujeres y el 12% de los hombres) coincidió en la selección visual del color con lo obtenido con espectrofotómetro. Un 76% de las mujeres y un 88% de los hombres no concordaron en la selección visual con respecto a los resultados obtenidos con el espectrofotómetro. Conclusiones Existen diferencias estadísticamente significativas entre la selección del color dentario con el método visual y el espectrofotómetro (p < 0,0005). El género no parecería ser un factor determinante en la selección del color (p < 0,232).

Introduction In cosmetic dentistry the selection of colour can be performed by visual or instrumental methods. The former is subjective, influenced by multiple factors and widely used by dentists, whilst the latter, using a spectrophotometer, is objective and simple but little used. Objective To compare the results in the selection of colour by a visual method and using the Easyshade Compact spectrophotometer, to verify whether there are differences between them. Material and method A total of 50 dentists, 25 men and 25 women, were asked to select the colour of a healthy anterior tooth using the 3D Master Vitapan, and the results were compared with those obtained when using the Easyshade Compact spectrophotometer. The data obtained were analysed using the Chi-squared statistical test. Results The colour obtained by the visual colour selection matched that obtained with spectrophotometer by 18% of dentists. The colour selection by the visual method was different to that obtained with the spectrophotometer for 76% of women and 88% of men. Conclusions There are statistically significant differences between the selection of colour with the visual method and with spectrophotometer (P < .0005). Gender does not seem to be a determining factor in the selection of colour (P < .232).

Eficiência de estudantes de Odontologia na seleção de cor com a escala Vita 3D-Master / Odontology students efficiency in color selection with Vita 3D-Master shade guide

A escala 3D-Master foi desenvolvida com a finalidade de satisfazer as maiores exigências estéticas dos pacientes, por possuir uma maior quantidade de tonalidades em relação às demais escalas. Contudo, possui uma técnica específica para a sua correta utilização, desconhecida por grande parte dos profissionais. O objetivo desse trabalho foi avaliar se, após o aprendizado da técnica correta de utilização da escala de cor VITA 3D-Master, recomendada pelo fabricante (VITA® Zahnfabrik, Alemanha), os profissionais da área de odontologia conseguem utilizá-la de forma adequada, atingindo o objetivo desejado que é a correta seleção de cor dos dentes. Para isso, foram utilizados seis elementos dentários de face vestibular hígida extraídos e doados pelos pacientes ao banco de dentes da faculdade. O terço médio da face vestibular de cada dente foi escolhido para a seleção de cor feita pelo espectrofotômetro digital VITA EasyShade programado para a escala VITA 3D-Master. Trinta e sete acadêmicos do último ano do curso de odontologia fizeram a seleção pelo método visual dos mesmos elementos dentários. Após a primeira seleção, uma palestra de 3 horas de duração foi ministrada por um técnico de prótese dental, ceramista e consultor da VITA®. Após essas orientações, os mesmos acadêmicos realizaram uma segunda seleção de cor com os mesmos elementos dentários, utilizando a técnica de seleção de cor da escala VITA 3D-Master. A técnica preconizada pela VITA® para a correta utilização da escala VITA 3D-Master impactou positivamente no resultado da segunda fase da pesquisa para a seleção de cor.

The 3D-Master shade guide was developed in order to meet higher patientsÆ aesthetic requirements as it has a greater number of shades when compared to other shade guides. However, a specific technique is needed for its correct use, which is unknown by most of professionals. The aim of this study was to evaluate if after learning the VITA 3D-Master shade guide correct technique use, recommended by the manufacturer (VITA® Zahnfabrik, Germany), dentistry professionals can use it properly, reaching the desired goal that is the correct selection of tooth color. For this, we used six extracted teeth of higid vestibular surface donated by patients to the university teeth bank. The middle third of the vestibular surface of each tooth was chosen for the color selection made by the digital spectrophotometer VITA Easyshade programmed for VITA 3D-Master shade guide. Thirty-seven students from the last year of the odontology course made the selection through the visual method in the same teeth. After the first selection, a 3 hours lecture was held by a qualified dental prosthetist, ceramist and VITA® consultant. After these guidelines, the same students performed a second color selection with the same teeth, using the VITA 3D-Master shade guide color selection technique. The technique recommended by VITA® for the correct use of VITA 3D-Master shade guide positively affected the outcome of the second phase of the research for color selection.

The incidental binding of color and shape is insensitive to the perceptual load

Abstract The binding of information in visual short-term memory may occur incidentally when irrelevant information for the task at hand is stored together with relevant information. We investigated the process of the incidental conjunction of color and shape (Exp1) and its potential association with the selection of relevant information to the memory task (Exp2). The results in Exp1 show that color and shape are incidentally and asymmetrically conjugated: color interferes with the recognition of shape; however, shape does not interfere with the recognition of color. In Exp2, we investigated whether an increase in perceptual load would eliminate the processing of irrelevant information. The results of this experiment show that even with a high perceptual load, the incidental conjunction is not affected, and color remains to interfere with shape recognition, suggesting that the incidental conjunction is an automatic process. (AU)

The Application of a New Maximum Color Contrast Sensitivity Test to the Early Prediction of Chiasma Damage in Cases of Pituitary Adenoma: The Pilot Study

PURPOSE: Our objective was to estimate the maximum color contrast sensitivity (MCCS) thresholds in individuals with chiasma opticum damage. METHODS: The pilot study tested 41 people with pituitary adenoma (PA) and 100 age- and gender-matched controls. Patients were divided into two groups according to PA size, PA ≤1 cm or PA >1 cm. A new MCCS test program was used for color discrimination. RESULTS: The mean total error score (TES) of MCCS was 1.8 in the PA ≤1 cm group (standard deviation [SD], 0.38), 3.5 in the PA >1 cm group (SD, 0.96), and 1.4 in the control group (SD, 0.31; p 1 cm (p < 0.01). In PA patients with normal VA, the TES was 2.35 times worse than that of healthy persons (p < 0.01).

Benign concentric annular macular dystrophy

The purpose of the authors is to show clinical findings of a patient with benign concentric annular macular dystrophy, which is an unusual condition, and part of the “bull’s eye” maculopathy differential diagnosis. An ophthalmologic examination with color perception, fluorescein angiography, and ocular electrophysiology was performed.

O objetivo dos autores é detalhar o quadro clínico de um paciente com distrofia macular anular concêntrica benigna, quadro raro, que compõe o diagnóstico diferencial das maculopatias em alvo. Realizou-se avaliação oftalmológica com auxílio de testes de percepção de cores, angiofluoresceinografia e eletrofisiologia ocular.

Reconhecimento de cores de objetos e de alimentos de cromaticidades opostas por pintos de corte / Recognition of colors of objects and food opposite chromaticities by broiler chicks

Objetivou-se com esta pesquisa avaliar, por meio de testes de preferência, a capacidade de percepção de pintos de corte no reconhecimento de objetos e alimentos de diferentes cores. A pesquisa foi realizada no Brasil e consistiu no condicionamento de 60 pintos de um dia sexados, sendo 30 pintos machos e 30 pintos fêmeas, durante três dias, com esferas azuis e alimento vermelho, cores escolhidas por terem cromaticidades opostas. Após a fase de condicionamento, foi realizado um teste de preferência, no qual os animais eram colocados individualmente no centro de uma arena de teste com quatro opções, sendo elas: alimento vermelho; alimento azul; esferas vermelhas; esferas azuis. Cada ave foi avaliada durante 10 minutos...

The aim of this research was to evaluate, by preference tests, the ability of perception of broiler chicks in the recognition of objects and foods of different colors. The survey was conducted in Brazil and consisted in the conditioning of 60 sexed one-day-old chicks using 30 male chicks and 30 female chicks for three days with blue balls and red food colors chosen for having opposed chromaticities. After the conditioning phase, a preference test was performed, in which the animals were placed individually in the center of an arena test with four options: red food, blue food, red balls and blue balls. Each bird was measured for 10 minutes...

Functional Magnetic Resonance Imaging Findings in Meares-Irlen Syndrome: A Pilot Sudy

PURPOSE: To investigate patterns of functional magnetic resonance imaging (fMRI) activation during sentence reading before and after wearing color-tinted lenses. METHODS: A total of 15 Meares-Irlen syndrome patients with a mean age of 23.4 years (range, 13 to 42 years) with no history of neurological or psychiatric disorders were scanned using a 3T MR scanner (Siemens, Tim-Trio, Germany). Each patient underwent two sessions of fMRI imaging (before and after MISViS color-tinted lens application). The fMRI paradigm included a block design of 20 seconds of rest (cross), 20 seconds of activation (sentence reading), and ten blocks (a total of 200 echo-planar image volumes) repeated for each session. Data preprocessing and analyses were performed using the SPM8 software package. RESULTS: The reading speed of patients improved more than 20% while wearing the selected lenses. When compared to the before-lens session, the after-lens session identified significant regions of activation in the left middle and superior temporal gyri (paired t-test; maximal z score, 5.38; Montreal Neurological Institute coordinate, -60 / -39 / 0; threshold at p < 0.05; corrected for multiple comparisons using family-wise error). No region of activation at the same threshold was found in the before-lens session as compared to the after-lens session. CONCLUSIONS: In the current study, we confirmed activation in the left middle and superior temporal gyri during sentence reading after wearing color-tinted lenses. These results could explain the effectiveness of color-tinted lenses in patients with Meares-Irlen syndrome.