Color stability and gloss of esthetic restorative materials after chemical challenges

Abstract This study evaluated gloss and color changes of esthetic restorative materials subjected to different acidic beverages. Specimens of resin composites (Z350XT (Z350), IPS Empress Direct (ED), Charisma Diamond (CD)) were prepared and the initial surface gloss and color (ΔE) were measured (n=10). Then, the specimens were immersed in 4 mL of each of the different beverages (cranberry juice; Coca-Cola; coffee or artificial saliva) during 15 min, 3x/day for 14 days and new gloss and color readings were obtained. Color change was evaluated with the ΔE formula and gloss change values were obtained by the formula: (final gloss - initial gloss). Data was submitted to two-way ANOVA followed by Tukey's post hoc test (a=0.05). CD showed the lowest color change among resin composites. The highest ΔE values were obtained after immersion in coffee and cranberry juice. Coffee promoted the highest gloss change (worst gloss retention), followed by cranberry juice, Coca-cola and artificial saliva (p<0.05). The type of beverage significantly influenced the gloss of resin composites. Coca-cola reduced gloss of the three resin composites in a similar manner. Coffee affected the ED gloss more than that of Z350 and CD, while cranberry juice affected Z350 more than ED and CD. Saliva had a more pronounced effect on the gloss retention of CD than ED. The beverages used in this study influenced the optical surface properties of the composites studied.

Resumo O objetivo foi avaliar as alterações de brilho e cor de materiais restauradores estéticos submetidos ao armazenamento em diferentes bebidas ácidas. Foram preparados espécimes de compósitos de resina (Z350XT (Z350), IPS Empress Direct (ED), Charisma Diamond (CD) e o brilho e a cor (ΔE) de superfície mensurados (n=10). Em seguida, os espécimes foram imersos em 4 mL de cada uma das diferentes bebidas (suco cranberry, Coca-Cola, café, ou saliva artificial) durante 15 min, 3x/dia durante 14 dias e o brilho e a cor novamente mensurados. A alteração de cor foi avaliada pela fórmula ΔE e os valores de alteração de brilho foram obtidos pela fórmula: (brilho final - brilho inicial). Os dados foram submetidos à ANOVA e Tukey (a = 0,05). CD apresentou menor alteração de cor quando comparado aos demais compósitos e maiores valores de ΔE foram obtidos após imersão em suco de café e cranberry. O café promoveu maior perda de brilho, seguido pelo suco cranberry, Coca-cola e saliva artificial (p <0,05). O tipo de bebida influenciou significativamente no brilho dos compósitos resinosos. Coca-cola reduziu o brilho dos três compósitos de maneira similar. O café promoveu maior alteração do brilho do ED, quando comparado ao Z350 e CD, enquanto o suco de cranberry afetou mais o Z350 do que o ED e o CD. A saliva teve efeito mais significativo na perda do brilho do CD do que o ED. As bebidas utilizadas neste estudo influenciaram as propriedades ópticas de superfície dos compósitos.

Alteraciones morfológicas en dientes sometidos a altas temperaturas con interés forense / Morphological changes in teeth exposed to high temperatures with forensic purposes

Los dientes son los elementos más resistentes del esqueleto humano y son utilizados en muchas ocasiones en la rutina de los laboratorios forenses. El objetivo de este estudio fue describir los cambios dentarios estructurales, morfológicos y del color que se producen tras la incineración, para ayudar en el manejo adecuado de las muestras en un escenario forense. Setenta dientes fueron expuestos a intervalos de temperatura de 100 °C a 1200 °C, durante 60 min. Un grupo control de 10 dientes no fue expuesto al choque térmico. Después de la incineración, los dientes fueron fotografiados y radiografiados para evaluar visualmente los cambios morfológicos. La medida del cambio de color fue realizada mediante un espectrofotómetro. Los resultados mostraron cambios estructurales y del color, así como alteraciones radiológicas, que se relacionaron con el intervalo de temperatura a la que fueron incinerados los dientes. En conclusión, es posible informar sobre la temperatura aproximada de calcinación de los dientes basándose en los cambios fotográficos, radiográficos y del color.

Teeth are the most resistant elements of the human skeleton and are thus often used in routine forensic research laboratories. The objective of this study was to describe structural, morphological and color changes that occur post heating the teeth to aid in proper handling of samples in a forensic scenario based on their condition. Seventy teeth were exposed to different temperature intervals, ranging from 100 °C to 1 200 °C for 60 min using a laboratory oven. Ten unheated teeth were used as controls for the study. After incineration, the teeth were photographed and radiographed to visually assess morphological changes. The measure of color change was performed with a spectrophotometer. The results showed structural and color changes as well as radiographic abnormalities, which were associated to the temperature interval at which the teeth were cremated. In conclusion, it is possible to inform about incineration tooth temperature based on photographic, radiographic and color changes.

In vitro Evaluation of Color Changes of Aesthetic Orthodontic Elastic Ligatures / Evaluación in vitro de los Cambios de Color en Ligaduras Elásticas Ortodónticas Estéticas

The objective of this study was to evaluate the possible changes in color of aesthetic elastic ligatures soaked in different solutions. Five different brands of aesthetic elastic ligatures were evaluated in the present study. Measurement of the discs´ color was performed using a reflectance spectrophotometer (UV-visible spectrophotometer, UV-2450, Shimadzu®, Kyoto, Japan). Subsequently, the discs were immersed in artificial saliva (AS) or three different solutions: red wine (RW) (Miolo Terranova® 2010, Casa Nova, Brazil), coffee (CF) (Café Três Corações®, RioGrande do Norte, Brazil) or Coca-Cola® (CC) (Coca-Cola®, Belo Horizonte, Brazil). It was determined that the tested solutions were able to cause color changes in the aesthetic elastic ligatures. The coffee solution caused the greatest color change in all of the brands of ligatures evaluated, followed by the red wine solution. In conclusion, OSE and GAC brands of aesthetic elastic ligatures displayed the best performance.

El objetivo de este estudio fue evaluar los posibles cambios en el color de ligaduras elásticas estéticas embebidas en diferentes soluciones. Cinco diferentes marcas de ligaduras elásticas estéticas fueron evaluados en el presente estudio. La medición de discos de color se realizó con un espectrofotómetro de reflectancia (espectrofotómetro UV-visible, UV-2450, Shimadzu®, Kyoto, Japón). A continuación, los discos se sumergieron en saliva artificial o tres soluciones diferentes: vino tinto (Miolo Terranova® 2010, Casa Nova, Brasil), café (Café Três Corações®, RioGrande do Norte, Brasil) o Coca-Cola® (Coca-Cola®, Belo Horizonte, Brasil). Se determinó que las soluciones testeadas fueron capaces de causar cambios de color en las ligaduras elásticas estéticas. La solución de café causó el mayor cambio de color en todas las marcas de ligaduras evaluados, seguido por la solución de vino tinto. En conclusión, las marcas de ligaduras elásticas estéticas OSE y GAC muestran el mejor desempeño.

Efecto de las condiciones de almacenamiento sobre el color, contenido de polifenoles y capacidad antioxidante de una bebida de Borojoa patinoi Cuatrecasas / Effect of storage conditions on color, polyphenol content and antioxidant capacity of a Borojoa patinoi Cuatrecasas beverage

In Latin America, popular tradition in some places have been attributed properties to borojó fruit, making it a potential source for the design and development of a functional product, but there is little scientific literature reference biological activity of this fruit. The aim of this study was to evaluate color changes, polyphenol content and antioxidant capacity of borojo (Borojoa patinoi Cuatrecasas) pulp beverage without chemical preservatives, it was stored at 4° C, 17° C and 37° C for 17 days. Coordinate a* was adjusted to zero order kinetics and the total polyphenol content (TP) and the antioxidant capacity (CA) had adjustments to first-order kinetics, suggesting a linear correlation between the degradation rates. The results showed that beverage storage at 4°C allowed a better retention of color changes, polyphenols and antioxidant compounds in nature, compared with the other storage temperatures.

En Latinoamérica, la tradición popular en algunas poblaciones le han atribuído al fruto del borojó propiedades, que lo hacen fuente potencial para el diseño y desarrollo de productos de carácter funcional; sin embargo es poca la literatura científica aún, que referencia alguna actividad biológica de este fruto. El objetivo de este trabajo fue evaluar los cambios de color, el contenido de polifenoles y la capacidad antioxidante de una bebida de pulpa de borojó (Borojoa patinoi Cuatrecasas.) sin conservantes químicos, ésta fue almacenada a 4º C, 17º C, y 37º C durante 17 días. En color la coordenada a* se ajustó a una cinética de orden cero; el contenido de polifenoles totales (PT) y la capacidad antioxidante (CA) presentaron ajustes a una cinética de primer orden, sugiriendo una correlación lineal entre las velocidades de degradación. Los resultados obtenidos indicaron que el almacenamiento de la bebida a 4° C permitió una mejor retención en los cambios de color, polifenoles y compuestos de carácter antioxidante, en comparación con las demás temperaturas de almacenamiento.

Color changing and behavioral context in the Amazonian Dwarf Cichlid Apistogramma hippolytae (Perciformes)

Animal coloration has many functions, and fishes are noted among vertebrates for presenting a wide variety of color patterns. Although in marine fishes the relationship between body coloration and behavioral context is well documented, there's not much information about freshwater fishes. Here we describe color patterns displayed by the dwarf cichlid Apistogramma hippolytae and suggest that these patterns are dependent on different social and behavioral settings. Field observations were conducted underwater in a pond in Central Amazonia, Brazil. We recorded six body coloration patterns related to seven different kinds of behavioral activities: foraging, resting, reproductive and agonistic displays, aggression (attacking and fleeing) and parental care. Changes in coloration occur rapidly and take only a few seconds. Females on parental care exhibited a unique pattern that are more persistent and probably manifests more slowly. In the shallow and clear waters of the natural environment of this dwarf cichlid, color communication seems to constitute an efficient way to display information about individual mood, social status and reproductive readiness, contributing to minimize loss of energy in unnecessary interactions.(AU)

Coloração animal tem diferentes funções, e os peixes se destacam entre os vertebrados por apresentarem uma grande diversidade de padrões de cores. Embora se conheça relativamente bem a relação entre coloração e contexto comportamental para peixes marinhos, pouco se sabe para os peixes de água doce. Nós descrevemos os padrões de coloração de um ciclídeo amazônico, Apistogramma hippolytae, e sugerimos como esses padrões são dependentes das características sociais e comportamentais. Realizamos observações subaquáticas utilizando mergulho livre em campo durante o dia em uma lagoa na Amazônia Central. Nós caracterizamos seis padrões de coloração associados a sete comportamentos diferentes: alimentação, repouso, displays sexual e agonístico, agressão (ataque e fuga) e cuidado parental. As mudanças de coloração levam apenas alguns segundos. Fêmeas em cuidado parental exibem um padrão exclusivo, cuja mudança é mais lenta. No ambiente natural desse ciclídeo, locais rasos com águas claras, a comunicação por coloração pode ser um sistema eficiente de comunicar o estado motivacional individual, status social e disposição para reprodução, possivelmente contribuindo para minimizar a perda de energia com interações desnecessárias.(AU)

Color changes in composites according to various light curing sources / 대한치과보존학회지

The purpose of this study was to evaluate the color changes of composite resin polymerized with three type of light curing units. Composite resin (Z100, shade A2) were applied in a cylindrical metal mold(2 mm thick, 7 mm diameter). Twenty specimens according to light curing units were made. Group1: the specimens were polymerized with Apollo 95E for 3seconds(1370 mW/cm2). Group2: the specimens were polymerized with XL 3000 for 40seconds(480 mW/cm2). Group3: the specimens were polymerized with Spectrum 800 for 10 seconds(250 mW/cm2) and 30 seconds(700 mW/cm2). The microhardness values(VHN) of upper and lower surfaces specimens after light polymerization were measured for the degree of polymerization. All specimens were stored in distilled water at 60degrees C for 30 days. The color characteristics(L*, a*, b*) of the specimens before and after immersion were measured by spectrophotometer and the total color difference (DeltaE*) was computed. The results obtained were as follows: 1. The microhardness values of Group I showed significantly lower than those of Group II and III(p<0.05). 2. In all groups the DeltaE* values presented below 2.0. 3. Group I showed the highest DeltaE* values followed order from highest to lowest by Group II and III (p<0.05).