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Introducción: Se han desarrollado materiales bioactivos para el recubrimiento pulpar directo con el objetivo de preservar la pulpa dentaria y mantener el diente por mayor tiempo en la cavidad oral. Objetivo: El objetivo de esta revisión fue evaluar la efectividad del uso de bioceramicos como material de recubrimiento directo pulpar para mantener la vitalidad pulpar en dientes primarios y permanentes con pulpitis reversible. Metodología: Se realizó una revisión sistemática con meta análisis. Se estudió el éxito en el tratamiento del mantenimiento de la vitalidad, el dolor postoperatorio y la decoloración. Se realizó una búsqueda Electrónica en las bases de datos: MEDLINE, EMBASE, COCHRANE, SCOPUS, LILACS, BBO. Se extrajeron los datos y se analizaron con Rev Man. Resultados: Se incluyeron ensayos clínicos aleatorizados en la cual se realizaron recubrimiento pulpar directo con silicatos tricalcicos comparado con otros materiales de recubrimiento. Comparando tres biocerámicos no se encontraron diferencias significativas en el mantenimiento de la vitalidad pulpar. En cuanto a la decoloración se observaron diferencias estadísticamente significativas a favor de Biodentine (p <0,001). Discusión: la relevancia clínica de estos hallazgos es discutible debido a su pequeña magnitud general y al alto riesgo de sesgo de los estudios incluidos.

Introduction: Bioactive materials have been developed for direct pulp capping in order to preserve the dental pulp and keep the tooth longer in the oral cavity. Objective: The objective of this review was to evaluate the effectiveness of the use of bioceramics as direct pulp capping material to maintain pulp vitality in primary and permanent teeth with reversible pulpitis. Methods: A systematic review with meta-analysis was performed. Success in treating vitality maintenance, postoperative pain, and discoloration was studied. An electronic search was carried out in the databases: MEDLINE, EMBASE, COCHRANE, SCOPUS, LILACS, BBO. Data were extracted and analyzed with Rev Man. Results: Randomized clinical trials in which direct pulp capping with tricalcium silicates was performed compared with other capping materials were included. Comparing three bioceramics, no significant differences were found in the maintenance of pulp vitality. Regarding discoloration, statistically significant differences were observed in favor of Biodentine (p <0.001). Discussion: the clinical relevance of these findings is debatable due to their small overall magnitude and the high risk of bias of the included studies.

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Advanced oxidation processes (AOP), using semiconductor (SC) and hydroxyapatite (HA) composites, are promising due to the synergy of photocatalytic and adsorption properties. Still, dye removal efficiency of composites based on HA-SC remains low, because most of the research reported consider single SC materials. In this work, nanocrystalline xerogels of titanium oxide (TiO2) with copper oxide (CuO) and HA were synthesized by the sol-gel process. HA was obtained by the precipitation method without heat treatment and calcined in the range of 200-1000 °C. TiO2 and copper precursors were added to a sol containing HA in a 12:1 mol ratio, obtaining HA-TiO2 and HA-CuO-TiO2 nanomaterials. The xerogels were characterized by X-ray diffraction, scanning electron microscopy, emission field scanning electron microscopy and photoresponse. Their performance in the photocatalytic discoloration of an aqueous solution acid yellow dye 36 (AY36) was evaluated, using visible and UV light. The best discoloration was achieved with HA-CuO-TiO2 xerogels with HA calcined at 600 °C, showing a degradation kinetic constant of 0.24 min-1. In contrast, HA-TiO2 materials showed little or no photocatalytic activity, but strong dye adsorption/desorption. The thermal treatment of HA determines the filament-like morphology and degree of compaction of the nanomaterials, which are relevant in the crystallite size and sensitization of the SC matrix. Further studies must address the surface chemistry and rectifying properties of the best SC composite to have a more complete understanding of the mechanisms involved.

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BACKGROUND: The presence of a vascular, blue linear discoloration on the nasal root of infants and young children is a frequent incidental feature, rarely reported in the medical literature. It is related to the trajectory of the transverse nasal root vein (TNRV). OBJECTIVE: To study the frequency and clinical characteristics of the vascular discoloration of the nasal root in children. METHODS: A prospective study was performed to address the presence or absence of vascular discoloration of the nasal root in all children under 6 years of age attending a pediatric dermatology clinic from November 2022 to November 2023. Data on age and skin phototype (Fitzpatrick classification I-VI) were also collected. RESULTS: Of 701 patients examined, 345 (49.2%) presented with a vascular discoloration of the nasal root. This was present in 97 of 193 (50.3%), 127 of 261 (48.7%), and 121 of 247 (49.0%) patients for the age groups 0-1, 1-3, and 3-6 years, respectively. The presence of vascular discoloration of the nasal root was more frequent in patients with lighter Fitzpatrick skin phototypes: 49 of 69 (71.0%) phototype II, 157 of 290 (54.1%) phototype III, and 137 of 337 (40.7%) phototype IV. CONCLUSIONS: A vascular discoloration of the nasal root is a frequent skin feature in infants and children, persisting at least until the age of 6. It does not constitute any medical problem aside from cosmetic concern and parents can be reassured of its benign nature. We propose the medical term "prominent TNRV" to describe this condition.

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This clinical trial investigated the effects of pre-application enamel moistening on the impact of a 37% carbamide peroxide whitener on tooth color changes and the influence of repositioning guide colors. Forty participants were randomly assigned to in-office tooth bleaching with either moistened enamel (experimental) or dry enamel (control). The whitener was applied for 45 min over two sessions. Tooth color was visually measured or assessed using a spectrophotometer with purple or green silicone guides. Tooth bleaching was assessed using CIE76 (ΔEab ) and CIEDE2000 (ΔE00 ) formulas and by whitening and bleaching index score changes. Moistening the enamel did not significantly affect tooth color. However, the guide color choice only impacted tooth color when measured instrumentally. At baseline, the green guide resulted in statistically significantly whiter teeth than the purple guide. Less pronounced differences in the b* coordinate between baseline and final measurements were found using the green guide. The green guide also produced lower ΔEab values and less change in indexes. In conclusion, moistening the enamel did not significantly impact tooth color changes. However, the repositioning guide color influenced the tooth bleaching measured instrumentally, except for ΔE00 .

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Abstract This in vitro study aimed to determine the efficacy of dentin bonding agents in preventing color changes following Regenerative Endodontic Procedures. One hundred twenty bovine incisors were endodontically prepared and randomly assigned to a two main factors design: application of a dentin bonding agent (Scotchbond Adper, 3M ESPE, St Paul, MN, USA) in the pulp chamber (Group 1, n=60) versus no bonding intervention (Group 2, n=60), and five levels of intracanal medication (n=12/subgroup): Triple antibiotic paste (TAP), double antibiotic paste (DAB), calcium hydroxide (CH), modified triple antibiotic paste (TAPM), and Control (CTL). Color changes were measured over 28 days at multiple time points (1, 3, 7, 14, 21, and 28 days) using the CIEDE2000 formula to calculate the color difference (ΔE00) from baseline (T0). The ΔE00 quantifies the perceptible color difference between the initial and final tooth color, with lower values indicating less discoloration. The results were analyzed using repeated measures ANOVA-2 and post-hoc Holm-Sidak tests. The TAP subgroups, both with and without the bonding agent, exhibited the highest color variation. However, a pulp chamber seal with a bonding agent showed a protective effect against discoloration compared to no seal, even though complete prevention was not achieved. All groups demonstrated ΔE00 values beyond acceptable interpretation thresholds for clinical application, primarily driven by a reduction in lightness (L*) and a decrease in redness (a* value, shifting towards green). In conclusion, while the pulp chamber seal with a bonding agent mitigated TAP-induced discoloration, it did not eliminate it.

Resumo Este estudo in vitro avaliou adesivos dentinários na prevenção de alterações de cor após procedimentos endodônticos regenerativos. Cento e vinte incisivos bovinos foram preparados endodonticamente e aleatoriamente designados para um desenho com dois fatores principais: aplicação de agente adesivo (Scotchbond Adper, 3M ESPE, St Paul, MN, EUA) na câmara pulpar (Grupo 1, n=60) versus não intervenção adesiva (Grupo 2, n=60), e cinco níveis de medicação intracanal (n=12/subgrupo): pasta de triantibiótica (TAP), pasta diantibiótica (DAB), hidróxido de cálcio (CH), pasta triantibiótica modificada (TAPM) e Controle (CTL). Alterações cromáticas foram monitoradas por 28 dias em intervalos (1, 3, 7, 14, 21, e 28 dias), usando CIEDE2000 para calcular a diferença de cor (ΔE00) em relação a cor inicial. O ΔE00 quantifica a diferença entre a cor inicial e final do dente, com valores menores indicando menos descoloração. Os resultados foram analisados usando ANOVA-2 de medidas repetidas e teste posthoc de Holm-Sidak. Os grupos utilizando medicação TAP, com ou sem adesivo, possuíram as maiores variações cromática. Contudo, o uso do adesivo na câmara pulpar mostrou um efeito protetor contra descoloração, em comparação com a ausência do selamento adesivo, embora a prevenção completa não tenha sido alcançada. Todos os grupos demonstraram valores de ΔE00 além dos limiares aceitáveis para aplicação clínica, principalmente devido à redução na luminosidade (L*) e redução no vermelho (a*, deslocando-se em direção ao verde). Em conclusão, enquanto o selamento da câmara pulpar com um agente adesivo mitigou a descoloração induzida pelo TAP, mas não a eliminou completamente.

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Objective: This study aimed to investigate of bioactive materials with specific properties, particularly highly plastic bioceramic cements. These materials are being studied extensively due to their potential to maintain pulp vitality and promote tissue regeneration. Material and Methods: Tooth discoloration induced by an experimental tricalcium silicate-based cement (EC) was evaluated and compared with that of Biodentine (BD) and white MTA-Angelus (MTA). Cavities were prepared on the lingual surfaces of thirty-two blocks of healthy bovine incisors. The blocks were chemically cleaned and then subjected to an initial color evaluation (CIELab values) using a spectrophotometer and randomly divided into three experimental groups (n=10); two additional blocks served as controls. After manipulation, the cements were placed in the cavities, which were subsequently restored with composite restorations. After another color measurement (baseline), they were immersed in bottles of distilled water; they were stored at 37 °C and 100% humidity for the entire test period. The color change (ΔE) was measured after 14, 30, 120 and 150 days. ANOVA and Tukey tests showed significant differences after 14 days (EC vs. MTA), 30 days (EC vs. BD) and 120/150 days (EC vs. BD/MTA) (p < 0.05). Results: All tested materials induced ΔE changes, with the EC group showing the least change at the end of the experiment (ΔE=4.08). Conclusion: EC induced less color change over a 5-month period and thus showed color stability over the entire period, whereas BD and MTA showed progressive discoloration. (AU)

Objetivo: O objetivo deste estudo foi investigar materiais bioativos com propriedades específicas, particularmente cimentos biocerâmicos altamente plásticos. Esses materiais estão sendo amplamente estudados devido ao seu potencial para manter a vitalidade da polpa e promover a regeneração dos tecidos. Material e Métodos: A descoloração dentária induzida por um cimento experimental à base de silicato tricálcico (CE) foi avaliada e comparada com a do Biodentine (BD) e do MTA-Angelus branco (MTA). Foram preparadas cavidades nas superfícies linguais de trinta e dois blocos de incisivos bovinos saudáveis. Os blocos foram quimicamente limpos e, em seguida, submetidos a uma avaliação inicial de cor (valores CIELab) usando um espectrofotômetro e divididos aleatoriamente em três grupos experimentais (n=10); dois blocos adicionais serviram como controles. Após a manipulação, os cimentos foram colocados nas cavidades, que foram posteriormente restauradas com compósito. Após outra medição de cor (valor de referência), eles foram imersos em frascos de água destilada; oram armazenados a 37 °C e 100% de umidade durante todo o período de teste. A alteração de cor (ΔE) foi medida após 14, 30, 120 e 150 dias. Os testes ANOVA e Tukey mostraram diferenças significativas após 14 dias (CE vs. MTA), 30 dias (CE vs. BD) e 120/150 dias (CE vs. BD/MTA) (p < 0,05). Resultados: Todos os materiais testados induziram alterações de ΔE, sendo que o grupo EC apresentou a menor alteração no final do experimento (ΔE=4,08). Conclusão: O EC induziu menos alterações de cor em um período de 5 meses e, portanto, apresentou estabilidade de cor durante todo o período, enquanto o BD e o MTA apresentaram descoloração progressiva.(AU)

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Abstract Repositioning guides are commonly employed in clinical studies to ensure consistent tooth color measurements. Yet, their influence on measured color remains uncertain. Objective This study evaluated the impact of repositioning guides' color and usage on tooth color measurement using a clinical spectrophotometer. Methodology In total, 18 volunteers participated in this study, in which the color of their upper left central incisor and upper left canine was measured with or without repositioning guides (control). The guides were made from pink, blue, or translucent silicone, as well as an acetate-based bleaching tray. Tooth color was measured in triplicates using a clinical spectrophotometer based on the CIELAB system. The standard deviations of these readings were used to estimate reproducibility, and color differences (ΔE00) between the measurements with guides and the control were calculated. Results Repositioning guides had a minimal effect on L* values and no effect on b* values. The use of pink silicone increased a* values, whereas blue or translucent silicone reduced them. Irrespective of the evaluated tooth, the lowest ΔE00 values were observed for the translucent silicone and bleaching tray. The usage of guides only affected data variability for the L* color coordinate. Conclusion Using repositioning guides can significantly impact the precision of tooth color measurement with a clinical spectrophotometer.

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The aim of this study was to evaluate the whitening and abrasion effects of dentifrices containing different whitening agents on artificially stained and unstained enamel. 160 human dental enamel discs were distributed into four groups according to the type of dentifrices applied on them (n=40): Group I, non-whitening dentifrice (control group); Group II, dentifrice containing charcoal; Group III, dentifrice containing blue covarine; Group IV, dentifrice containing hydrogen peroxide. Half of the specimens in each group were immersed in coffee solution. Color measurements were evaluated from stained and unstained specimens before and after brushing by a spectrophotometer. The surface roughness of each unstained specimen was analyzed using a profilometer after the brushing and bleaching. The surface of one randomly selected specimen from each group was observed using a scanning electron microscope (SEM). Statistical analysis of the color change was performed using the Kruskal-Wallis test. The one-way ANOVA was used to evaluate surface roughness. Group III provided significantly higher recovery on ΔE00 values than other groups on the unstained enamel (p<0.05). Group IV showed significantly the highest ΔE00 values on stained enamel (p<0.05) and also Group IV showed the highest surface roughness values (p<0.05), SEM revealed a more irregular surface in groups III and IV. It can be stated that dentifrice containing blue covarine is both an effective and a safe way to provide whiter teeth with routine home tooth brushing.

El objetivo de este estudio fue evaluar los efectos de blanqueamiento y abrasión de los dentífricos que contienen diferentes agentes blanqueadores en el esmalte teñido y no teñido artificialmente. Se distribuyeron 160 discos de esmalte dental humano en cuatro grupos según el tipo de dentífrico aplicado sobre ellos (n=40): Grupo I, dentífrico no blanqueador (grupo control); Grupo II, dentífrico que contiene carbón vegetal; Grupo III, dentífrico que contiene azul; Grupo IV, dentífrico que contiene peróxido de hidrógeno. La mitad de los especímenes de cada grupo se sumergieron en una solución de café. Las mediciones de color se evaluaron a partir de especímenes teñidos y no teñidos antes y después del cepillado con un espectrofotómetro. La rugosidad de la superficie de cada muestra sin teñir se analizó utilizando un perfilómetro después del cepillado y del clareamiento. La superficie de un espécimen seleccionado al azar de cada grupo se observó utilizando un microscopio electrónico de barrido (MEB). El análisis estadístico del cambio de color se realizó utilizando la prueba de Kruskal-Wallis. Se utilizó el ANOVA para evaluar la rugosidad de la superficie. El grupo III proporcionó una recuperación significativamente mayor en los valores de ΔE00 que otros grupos en el esmalte no teñido (p<0,05). El Grupo IV mostró significativamente los valores más altos de ΔE00 en el esmalte teñido (p<0.05) y también el Grupo IV mostró los valores más altos de rugosidad superficial (p<0.05), el análisis en MEB reveló una superficie más irregular en los grupos III y IV. Se puede afirmar que el dentífrico que contiene azul es una forma efectiva y segura de proporcionar dientes más claros con el cepillado de rutina en el hogar.

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RESUMEN La discromía de piezas dentarias es un problema clínico frecuente en la práctica dental que llega a ser una preocupación estética que puede afectar a la autoestima del paciente. Aunque la técnica de blanqueamiento interno está asociada a resultados óptimos a largo plazo, existen casos en donde no es posible realizar una apertura cameral. Por lo tanto, el presente reporte de casos muestra el uso del blanqueamiento externo con las técnicas en consultorio y domiciliaria en dientes oscurecidos donde se consiguió con éxito restaurar el color natural de forma conservadora.

ABSTRACT Discoloration of teeth is a common clinical issue in dental practice, often posing an aesthetic concern that may impact the patient's self-esteem. While the internal bleaching technique usually offers favorable long-term outcomes, situations arise where chamber opening is not viable. In such instances, this case report highlights the application of external bleaching through both in-office and at-home methods. These techniques were employed to address darkened teeth, successfully restoring their natural color using a minimally invasive approach.

RESUMO A discromia dental é um problema clínico comum na prática odontológica, que se torna uma preocupação estética capaz de afetar a autoestima do paciente. Embora a técnica de clareamento interno esteja associada a ótimos resultados em longo prazo, existem casos em que a abertura da câmara não é possível. Portanto, o presente relato de caso mostra o uso de clareamento externo com técnicas no consultório e em casa em dentes escurecidos, nos quais a cor natural foi restaurada com sucesso de maneira conservadora.

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O tratamento estético de dentes com alteração de cor é um grande desafio na Odontologia Restauradora. Nesse sentido, a utilização de técnicas de estratificação com resina composta associada ao uso de pigmentos opacificadores permite que seja possível restaurar por meio de uma técnica direta, que resulta em um menor desgaste da estrutura dental durante o preparo. Dessa forma, o presente trabalho apresenta um caso clínico de faceta direta de resina composta utilizando associação de três pigmentos opacificadores. Paciente do sexo masculino, 54 anos, procurou atendimento apresentando alteração de cor severa do dente 21, relato de trauma dental, tratamento endodôntico e contraindicação de novo protocolo de clareamento interno, sendo sugerido, como plano de tratamento, a restauração direta com resina composta. Para a confecção da faceta direta de resina, foi utilizada uma mistura de três opacificadores na consistência fluida. Para verificar o valor da camada aplicada da mistura, foram feitas fotografias em preto e branco. A estratificação prosseguiu com camadas de resina translúcida para a base palatina, resina opaca de dentina e resina acromática translúcida para o esmalte. Como resultado, constatou-se a função e eficácia do uso da associação de pigmentos opacificadores na resolução do caso, em seguida, foi realizada uma reavaliação após 30 dias e 7 meses do procedimento restaurador, quando verificou-se a estabilidade de cor da restauração. Concluiu-se, portanto, que a utilização da técnica de estratificação de resinas compostas associada a utilização de pigmentos opacificadores traz resultados estéticos satisfatórios e favoráveis por meio de uma técnica direta, realizada em sessão clínica única e com alta previsibilidade.

The esthetic treatment of teeth with discoloration is a major challenge in restorative dentistry. In this sense, the use of composite resin veneering techniques associated with the use of opacifying stains allows restorations to be made using a direct technique, which results in less wear to the tooth structure during preparation. Thus, the present study presents a clinical case of a direct composite resin veneer using an association of three opacifying pigments. A 54-year-old male patient presented with severe color change on the central upper left incisor, a report of dental trauma, endodontic treatment, and contraindication for a new internal bleaching protocol. In order to make the direct resin veneer, a mixture of three opacifiers in a fluid consistency was used. To check the value of the applied layer of the mixture, black and white photographs were taken. Layering proceeded with translucent resin layers for the palatal base, opaque dentin resin and translucent achromatic resin for the enamel. As a result, the function and efficacy of the use of the association of opacifying pigments was verified in the resolution of the case. A reevaluation was performed 30 days and 7 months after the restorative procedure, when the color stability of the restoration was verified. This case allows to conclude that using composite resin layering technique associated with the use of opacifying pigments brings satisfactory and favorable aesthetic results through a direct technique, performed in a single clinical session and with high predictability.

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INTRODUCTION: Regenerative endodontic procedures provide conditions for the continuity of apical formation and increase of the dentin wall thickness, being a useful technique to resume root development of necrotic teeth with incomplete apex. This study aimed to evaluate the coronal discoloration promoted by a new intracanal calcium silicate-based dressing and compare it with other intracanal dressings used in regenerative endodontic procedures. METHODS: Sixty bovine incisors were prepared to simulate teeth with incomplete apexes and divided according to the intracanal dressing used: triple antibiotic paste-double antibiotic paste-DAP, calcium hydroxide associated with 2% chlorhexidine gel, calcium hydroxide associated with saline solution, and Bio-C Temp. As control, no dressing was performed. The intracanal dressings remained in the simulated root canal for 21 days. Luminosity (ΔL) and color difference (ΔEab and ΔE00) were evaluated using long-term (1 year) spectrophotometric analysis. The results were analyzed using the ANOVA test with Tukey post hoc with a significance of 5%. RESULTS: Triple antibiotic paste showed the highest values of ΔEab and ΔE00 and lowest values of ΔL (P < .05). Bio-C Temp showed higher ΔEab than the other groups from 6 months (P < .05), higher ΔE00 and lower ΔL after 1 year (P < .05). CONCLUSIONS: Bio-C Temp induced noticeable coronary discoloration after the 1-year analysis.

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In this study, we evaluated, in a pioneering way, the influence of wavelengths from the decomposition of white light on the production and physicochemical properties of silver nanoparticles (AgNPs). Bearing in mind a process of green synthesis, an extract of the bracts of Bougainvillea glabra Choisy (BgC) was used, a species native to tropical and subtropical regions and frequently used in ornamentation, possessing in its photochemical composition, biomolecules capable of acting as reducing agents for convert Ag+ to Ag0. We used light-emitting diodes (LED) to obtain the desired wavelengths (violet, blue, green, yellow, orange, and red) in the test called rainbow, and we evaluated the obtaining of AgNPs compared to white LED light, nature, and absence of light. In the rainbow assay, we obtained a gradual increase in the intensity of the plasmonic band resonance from the red wavelength (0.124 ± 0.067 a.u.) to violet (0.680 ± 0.199 a.u.), indicating a higher reaction yield in obtaining AgNPs. Smaller hydrodynamic sizes (approximately 150 nm) at more energetic wavelengths (violet, blue, and green) about less energetic wavelengths (yellow, orange, and red) (approximately 400 nm) were obtained. Analysis by SEM microscopy, FTIR spectroscopy, and X-ray diffraction indicates the presence of silver nanoparticles in all LED colors used together with white LED light and Laboratory light (natural light). Due to the high environmental demand to remove pollutants from water sources, including textile dyes, we applied AgNPs/BgC to remove methylene blue (MB) dye from an aqueous solution. A minimum removal percentage greater than 65%, with emphasis on formulations synthesized by the colors of violet LED (84.27 ± 2.65%) and orange LED (85.91 ± 1.95%), was obtained.

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This review will provide a better understanding of a set of signs known as malarial retinopathy. The discovery of this retinopathy in association with cerebral malaria is important because it best distinguishes patients with true cerebral malaria from those with coma due to other causes and incidental Plasmodium falciparum parasitemia. Identifying a comatose patient with malarial retinopathy increases the likelihood of an accurate severe or cerebral malaria diagnosis. As the World Health Organization does not specify that malarial retinopathy is one of the factors included in determining a cerebral malaria diagnosis, there are significant false-positive diagnoses of cerebral malaria. Once a cerebral malaria diagnosis is assigned, other possibilities and treatments are often excluded making an incorrect diagnosis of cerebral malaria potentially fatal. However, Plasmodium falciparum may also contribute to coma in some children with retinopathy-negative cerebral malaria, as this group is still not clinically well characterized, so all children with the WHO definition of cerebral malaria should be treated for severe malaria. Nevertheless, by raising awareness about malarial retinopathy, there could be a greater potential to accurately diagnose cerebral malaria and thus achieve more positive patient outcomes in the future. This literary review aims to raise awareness of the retinopathy by defining what it is to non-experts, explaining its pathology, clarifying the techniques needed to accurately diagnose malarial retinopathy, as well as the barriers that prevent clinicians from providing a proper diagnosis in malaria-endemic regions; and finally, discuss future directions to continue the study of malarial retinopathy.

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OBJECTIVE: To map the existing evidence regarding the masking ability of resin composites. OVERVIEW: The literature search was conducted electronically, based on the PRISMA Extension for Scoping Reviews-online protocol at https://osf.io/m2h67/ with no language or time restrictions. Two independent reviewers conducted the screening, and a third reviewer was consulted in case of disagreement. Studies that evaluated resin composite masking ability regardless of background, application technique, thickness, or number of layers were selected. The search found 2995 potentially eligible studies. After removal of duplicates (657), irrelevant articles (2323), 15 citations met the eligibility criteria based on title and abstract, and eight studies were included based on full text analysis (seven in vitro, and one case report). Acceptable masking ability is obtained by one layer of opaque shade resin composite or by the layering technique. A black background is masked with 1.0- to 2.0 mm-thick layers of opaque shade resin composites. Masking of the C4 background is achieved with one layer of 0.5- to 1.5 mm-thick opaque shade resin composite or by the layering technique using different combinations of enamel body and dentin shades with a final thickness of 1.5 mm. CONCLUSIONS: Acceptable masking of C4 shade background is achieved with one layer of opaque shade composite at least 0.5 mm-thick or by different combinations of the layering technique, with a final thickness of 1.5 mm. Acceptable masking of the black background of the oral cavity is achieved with a resin composite of at least 1.0 mm opaque shade. CLINICAL SIGNIFICANCE: The thickness of the resin composite layer required to achieve adequate masking is variable and depends on the translucency/opacity of the tested resin composites and the background shade.

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OBJECTIVE: We aimed to evaluate the color and oxidative stability of beef gluteus medius (GM) from cattle raised in organic and non-organic production systems. METHODS: The GM samples (n = 10) were obtained from organic (ORG; n = 5) or non-organic (NORG; n = 5) beef samples, sliced into 2.54-cm steaks, packaged in aerobic conditions, and stored for nine days at 4°C. ORG and NORG steaks were compared regarding myoglobin concentration, pH, instrumental color, delta E (ΔE), metmyoglobin reducing activity (MRA), and lipid oxidation on days 0, 5, and 9. RESULTS: Feeding system did not influence (p>0.05) the myoglobin concentration. ORG steaks exhibited greater (p<0.05) meat pH, yellowness, and MRA, whereas NORG steaks exhibited greater (p<0.05) redness, chroma, R630/580, delta E, and lipid oxidation. ORG and NORG steaks exhibited similar (p>0.05) lightness and hue angle. During storage, ORG and NORG exhibited an increase in muscle pH, hue angle, and lipid oxidation; and a decrease (p<0.05) in redness, yellowness, chroma, and color stability (R630/580). Both samples exhibited a stable (p>0.05) pattern for lightness and MRA. CONCLUSION: Therefore, the production system can affect beef color and lipid stability during storage.

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Abstract Few long-term studies assess the discoloration induced by hydraulic calcium silicate-based cement on dental structures. In addition, as far as we know, no long-term study has assessed the discoloration induced by these cement on composite resin. Objective This in vitro study aimed to assess, during a period of two years, the discoloration potential of different hydraulic calcium silicate-based cements (hCSCs) on the enamel/dentin structure and composite resin restoration. Methodology A total of 40 enamel/dentin discs were obtained from bovine incisors, and 40 composite resin discs (10 mm in diameter × 2 mm thick) were fabricated. A 0.8 mm-deep cavity was made in the center of each disc and filled with the following hCSCs (n=10): Original MTA (Angelus); MTA Repair HP (Angelus); NeoMTA Plus (Avalon); and Biodentine (Septodont). An initial color measurement was performed (T0 - baseline). After 7, 15, 30, 45, 90, 300 days, and two years, new color measurements were performed to determine the color (ΔE00), lightness (ΔL'), chroma (ΔC'), hue differences (ΔH'), and whiteness index (WID). Results For enamel/dentin, the ΔE00 was significant among groups and periods (p<0.05). NeoMTA Plus had the greatest ΔE00. The NeoMTA Plus group had the greatest ΔE00 after two years for composite resin. Significant reduction in lightness was observed for all groups after two years (p<0.05). The most significant WID values were observed after 30 days for Biodentine (enamel/dentin) and MTA Repair HP groups (composite resin) (p<0.05). Conclusions The hCSCs changed the colorimetric behavior of both substrates, leading to greater darkening over time. The Bi2O3 in the Original MTA seems relevant in the short periods of color change assessment.

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O dano capilar causado pelo descolorimento oxidativo é muito intenso, sendo que dois fatores são responsáveis por essa ação: primeiro, a ação direta e danosa do oxidante em diversas estruturas capilares e segundo, o dano oxidativo primário facilita o dano causado por outros agentes físicos (luz, temperatura) e químicos (tensoativos), que comumente tem ação nos cabelos. Desenvolver conceitos e tecnologias que possam tornar o oxidante específico para a melanina e por conseguinte efetuando o descolorimento sem causar danos ao fio é extremamente desejável. Neste trabalho buscaremos entender de que forma a luz visível pode aumentar a ação do oxidante sem danificar o fio colateralmente. O objetivo principal deste trabalho é demonstrar que é possível utilizar a luz visível, que é absorvida pela melanina, para tornar esse pigmento mais suscetível ao agente oxidante e desta forma, permitir que o descolorimento seja realizado com concentrações pequenas de oxidante. Também almejamos desenvolver métodos de análises por microscopia ótica de fluorescência e de reflexão para mensurar o dano nas estruturas dos fios processados com oxidante e na presença ou ausência da luz

The capillary damage caused by oxidative discoloration is very intense, and two factors are responsible for this action: first, the direct and harmful action of the oxidant on several capillary structures and second, the primary oxidative damage facilitates the damage caused by other physical agents (light, temperature) and chemicals (surfactants), which commonly have action on the hair. Developing concepts and technologies that can make the oxidant specific to melanin and therefore discoloring without causing damage to the hair is extremely desirable. In this work we will try to understand how visible light can increase the oxidant's action without damaging the wire collaterally. The main objective of this work is to demonstrate that it is possible to use visible light, which is absorbed by melanin, to make this pigment more susceptible to the oxidizing agent and, thus, to allow the discoloration to be carried out with small concentrations of oxidizer. We also aim to develop methods of analysis by optical fluorescence and reflection microscopy to measure the damage to the structures of the threads processed with oxidizer and in the presence or absence of light

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Abstract This laboratory study aimed to evaluate the influence of endodontic sealer and cervical limit of root filling on the discoloration of root canal treated teeth. Bovine incisors were randomly distributed into six experimental groups and control (n=21/group), according to the endodontic sealer used [AH Plus (AP); MTA Fillapex (MF) and Sealer Plus BC (SPB)] and the cervical limit of root filling [dental cervix (DC) or 2 mm in apical direction (2mm-AD)]. Tooth discoloration (ΔE) was evaluated by a digital spectrophotometer using the CIED2000 method. Color assessments were performed immediately before (baseline), 1 week, 1, 3, 6 months, and 1 year after obturation. Data were analyzed by ANOVA and Tukey's post-hoc tests (α=5%). Teeth filled with the three sealers showed perceptible tooth discoloration (ΔE≥2.7) in 1 week, maintaining similar values over time. There was a significant difference between MF and SPB sealers in the 2mm-AD groups. In addition, 2mm-AD groups promoted significantly lower discoloration than DC groups for AH (3 months) and SPB (1 and 3 months) sealer,s. Teeth filled with AP, MF, and SPB sealers displayed discoloration from 1 week to one year, with differences between MF and SPB sealers. A cervical limit of filling material at 2 mm from the dental cervix seems more advisable, promoting lower crown discoloration.

Resumo O presente estudo laboratorial teve como objetivo avaliar a influência do cimento endodôntico e do limite cervical da obturação radicular na alteração de cor de dentes tratados endodonticamente. Incisivos bovinos foram distribuídos aleatoriamente em seis grupos experimentais e um controle (n=21/grupo), de acordo com o cimento endodôntico utilizado [AH Plus (AP); MTA Fillapex (MF) e Sealer Plus BC (SPB)] e o limite cervical da obturação [Colo dentário (CD) ou 2mm na direção apical (2mm-DA)]. A alteração de cor (ΔE) foi avaliada por um espectofotômetro digital usando o método CIED2000. As avaliações de cor foram realizadas imediatamente antes (baseline), 1 semana, 1, 3, 6 meses e 1 ano após a obturação. Os dados foram analisados pelos testes ANOVA e post-hoc de Tuckey (α=5%). Dentes obturados com os três cimentos apresentaram alteração de cor perceptível (ΔE≥2.7) em 1 semana, mantendo valores semelhantes ao longo do tempo. Houve uma diferença significativa entre os cimentos MF e SPB nos grupos 2mm-DA. Além disso, os grupos 2mm-DA promoveram uma alteração de cor significativamente menor do que o grupos CD para os cimentos AH (3 meses) e SPB (1 e 3 meses). Os dentes obturados com os cimentos AH, MF e SPB apresentaram alteração de cor entre 1 semana a um ano, com diferenças entre os cimentos MF e SPB. O limite cervical do material obturador a 2mm do colo dentário parece mais aconselhável, promovendo menor alteração de cor da coroa dentária.

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Aim: The objective of this study was to describe a case series concerning internal bleaching of anterior traumatized teeth that underwent regenerative endodontic procedures (REP). Methods: Seven non-vital maxillary anterior teeth discolored after regenerative endodontic procedures were included and divided into two groups according to the medication protocol used in the REP: (1) Triple antibiotic paste (TAP) group (n=4); (2) Calcium hydroxide and 2% chlorhexidine gel (HC+CHX) (n=3). The bleaching technique used was walking bleach, where sodium perborate associated with distilled water was used. Bleaching agent was replaced weekly until the darkened tooth was slightly lighter than the adjacent tooth. The color was recorded with the aid of a digital spectrophotometer in two moments (T1: prior the first session of bleaching, T2: fourteen days after the last session of bleaching). The change in color after the procedure (ΔE) was calculated and reported in a descriptive analysis. Results: The ΔE for all teeth showed color differences exceeding the perceptibility threshold (ΔE > 3.7). Both groups showed similar ΔE (TAP: 18.3 ± 11.5; HC+CHX: 14 ± 11.2) at the end of the treatment. The average number of sessions needed to achieve satisfactory results was 1.7 ± 0.6 for HC+CHX group and 2.3 ± 0.5 for TAP group. Conclusion: Internal bleaching with sodium perborate associated with distilled water is effective in treating discolored teeth after regenerative endodontic procedures

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Antioxidants are used to prevent oxidation reactions and inhibit the development of unwanted sensory characteristics that decrease the nutritional quality, acceptance, and shelf-life of processed meat products, improving their stability. Synthetic antioxidants, although efficient, are related to the development of diseases because they present toxic and carcinogenic effects. Thus, researchers and the meat industry are studying natural alternatives to synthetic antioxidants to be used in meat products, thus meeting the demand of consumers who seek foods without additives in their composition. These natural extracts have compounds that exert antioxidant activity in different meat products by different mechanisms. Thus, this review work aimed to gather studies that applied natural extracts derived from different plant sources as possible antioxidants in meat products and their action in preserving the quality of these products.

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