Long-term fracture load of all-ceramic crowns : effects of veneering ceramic thickness, application techniques, and cooling protocol

To evaluate, in vitro, the effects of the cooling protocol, application technique, and veneering ceramic thickness on the fracture resistance of ceramic crowns with Y-TZP frameworks. 80 frameworks were made from zirconia by the CAD/CAM technique and divided into 8 groups (n = 10) according to the factors: ?application technique? (stratified-L and pressed -P), ?thickness? (1 mm and 2 mm), and ?cooling protocol? (slow-S and fast-F) of the feldspathic veneering ceramic. After, all crowns were cemented over G10 preparations with resin cement (Panavia F, Kuraray), mechanically cycled (2x106 cycles, 200 N, 3Hz), and subjected to the axial compression resistance test (0.5 mm/min, 10 kN). The data (N) underwent descriptive statistical analysis by 3-way ANOVA and Tukey?s test (5%). Fracture analysis was performed to determine the possible origin of failure. The factors ?cooling protocol? (P=0.0058) and ?application? technique (P=0.0001) influenced the fracture resistance of the crowns. For pressed veneer technique, the P2S (4608.9±464.5). A presented significantly higher results than that P2F(3621.1±523.0)BCD (Tukey?s test). For the stratified technique, this difference was not observed (P>0.05). The thickness of the veneering ceramic was not significant regardless of the cooling protocol and technique (P>0.05). The predominant failure mode was chipping of the ceramic veneer originating in the subsurface. The pressed technique, used with a slow-cooling protocol, leads to the best outcome for the veneering of all-ceramic crowns

Domestic activity and socialization: the viewpoint of adolescents from different socioeconomic classes

A rotina familiar desempenha papel fundamental na socialização e é parte constituinte da cultura íntima da família. Dentre as atividades de rotina, a tarefa doméstica (TD) tem sido apontada como uma das estratégias para investigar tópicos centrais do desenvolvimento humano. Assim, o estudo dos sentidos atrelados a esta atividade pode fornecer indicativos dos processos de socialização. O objetivo desta pesquisa foi conhecer e discutir a visão dos adolescentes de classes economicamente distintas acerca dessa atividade. Participaram dois grupos de adolescentes com idade de 12 a 15 anos, o primeiro caracterizado como baixa renda (GBR), composto por dez participantes, sendo cinco de cada sexo; e o segundo como classe média (GCM), do qual fizeram parte onze adolescentes, três meninas e oito meninos. Os instrumentos utilizados foram: um questionário sócio-demográfico e um roteiro de entrevista semi-estruturado, sendo os dados coletados por meio de dois Grupos Focais. Nos resultados foi identificado que os grupos apresentaram temáticas similares, tais como, diferenciação de gênero, democracia doméstica e aquisição de habilidades. Contudo os sentidos construídos pelo GBR e o GCM acerca das TDs foram em sua maioria diferentes, pois o GBR deu maior ênfase à participação na tarefa doméstica como promotora de sobrevivência familiar e oportunidades desenvolvimentais.Family routine plays a fundamental role in socialization, and is an important feature of intimate family culture. Among the routine activities, the study of domestic tasks (DT) has been identified as a key strategy for investigating issues dealing with human development. Thus, meanings associated with DT may be used as indicators of certain socialization processes. The aim of this investigation was to identify and discuss the viewpoints of adolescents from different socioeconomic classes regarding DT. Two groups of adolescents aged between 12 and 15 years participated in the study: 10 adolescents (five of each sex) from lower-income families (LIF), and 11 (3 girls and 8 boys) from middle-income families (MIF). A socio-demographic questionnaire and a semi-structured interview were used, and data were collected through two Focal Groups. Both groups yielded similar themes, such as gender differentiation, domestic sharing, and skill acquisition. However, the DT meanings constructed by LIF adolescents differed from those constructed by MIF adolescents, because those from the former group tended to consider participation in the domestic task as important for family survival and developmental opportunities

AVANÇOS RECENTES NO DIAGNÓSTICO PRECOCE DO CÂNCER DE PULMÃO: UMA ANÁLISE DE REVISÕES SISTEMÁTICAS

The high mortality rate from lung cancer, the leading cause of cancer death in Brazil, highlights the urgent need for effective screening and early diagnosis policies. Late detection, often in advanced stages, compromises treatment options. The aim of this study was to reflect on the importance of recent advances in the early diagnosis of lung cancer. A systematic literature review was carried out using the Scielo, Lilacs and Medline databases. After a qualitative analysis of the results, it was concluded that early identification of the disease allows for more effective therapeutic interventions, resulting in greater survival and better clinical outcomes for patients.A alta taxa de mortalidade pelo câncer de pulmão, principal causa de óbito por câncer no Brasil, ressalta a urgência de políticas efetivas de rastreamento e diagnóstico precoce. A detecção tardia, frequentemente nos estágios avançados, compromete as opções de tratamento. Este estudo teve como objetivo refletir sobre a importância do avanços recentes no diagnóstico precoce do câncer de pulmão. Para isso, foi desenvolvida uma revisão sistemática da literatura, utilizando as bases de dados Scielo, Lilacs e Medline. Após análise qualitativa dos resultados, concluiu-se que a identificação precoce da doença permite intervenções terapêuticas mais eficazes, resultando em maior sobrevida e melhores resultados clínicos para os pacientes

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Análise da profundidade de desgaste e da perda mineral no esmalte subjacente à microabrasão após técnica microabrasiva.

The main effect of the microabrasion in the enamel is significant erosion. However, there is a gap in the literature about validated and reproducible assessment of the depth of erosion in the enamel surface which is originally curve. AIMS: Evaluate depth of erosion and mineral loss of enamel produced by microabrasion technique in original coronary surface of human teeth. METHODS AND MATERIALS: 40 extracted human molars were randomly spited in four groups, with 10 specimens each, in accordance with the microabrasive treatment: AC- 18% hydrochloric acid and pumice, AF 37% phosphoric acid and pumice, OP Opalustre and WRM Whiteness RM. Each specimens had buccal surface´s laterals isolated so that the central area received the microabrasion treatment. After this procedure, transverse slices not demineralized were prepared and submitted to microradiography and analysis in Polarized Light Microscope. One own terminology had created for the morphology of the interface enamel normal-microabrasioned. This served as base to introduction of a profilometry technique with analysis of digital images, in order to get the depth of erosion on microabrasion´s area. The Intraclass Correlation Test was applied to test technique´s reproducibility. The mineral loss and the depth which it happened had analyzed by transverses plotted at equidistant points of the limit enamel normal-microabrasioned. The dates were analyzed with ANOVA test (p < 0.05). RESULTS: The profilometry technique achieved a good reproducibility (Intraclass Correlation Test of 0,9998) and was validated internally. The AC group was the most aggressive, with a greater depth of erosion (110,51 ± 41,21 &#956;m), and a greater mineral loss (13 ± 3 peso %), with significant difference between WRM group (p < 0,05; 9,41± 4,4 peso %) and OP group (p < 0,05; 9,0 ± 3,8 peso %). The OP group, on the other hand, was the less aggressive, with the lowest values in all parameters analyzed, presenting depth of erosion less than AC group (p < 0,0001), WRM group (p < 0,001; 86,24 ± 27,99 &#956;m) and AF group (p < 0,05; 74,46 ± 42,06 &#956;m). The others two groups achieved intermediate results for depth of erosion and mineral loss. The depth of mineral loss was greater than on AF group (31,38 ± 20,30 &#956;m), however, there wasn´t statistical difference between the groups. CONCLUSIONS: Based on own terminology for the interface enamel normalmicroabrasioned and on the implementation of new technique of profilometry, the agents tested showed a significant difference in the depth of erosion, which was consistent with the mineral loss. However, there wasn´t difference in the depth of mineral loss. Furthermore the new technique of profilometry is proposed to fill a gap in the literature, allowing the determination of physical depth of erosion in areas naturally curves of hard biological tissues.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorO principal efeito da microabrasão no esmalte dental é uma erosão significativa. Porém, existe uma lacuna na literatura no que concerne à avaliação validada e reprodutível da profundidade de desgaste na superfície dental natural. OBJETIVOS: Avaliar a profundidade de desgaste e a perda mineral do esmalte dentário resultante da técnica de microabrasão na superfície coronária original de dentes humanos. MATERIAIS E MÉTODOS: 40 terceiros molares humanos extraídos foram divididos aleatoriamente em 4 grupos, de 10 espécimes cada, de acordo com o material microabrasivo utilizado: AC - ácido clorídrico a 18% e pedra-pomes, AF - ácido fosfórico a 37% e pedra-pomes, OP - Opalustre® e WRM - Whiteness RM®. Cada elemento teve as laterais da face vestibular protegidas para que apenas a área central fosse exposta aos agentes microabrasivos. Após o procedimento de microabrasão, cortes transversais não desmineralizados foram preparados e submetidos à radiomicrografia e análise em Microscopia de Luz Polarizada. Uma terminologia própria foi formulada para a morfologia da interface esmalte normalmicroabrasionado. Esta serviu de base à introdução de uma Técnica de Perfilometria com Análise de Imagens Digitais, com o intuito de obter a profundidade de desgaste ao longo da área microabrasionada. O teste de correlação intraclasse foi aplicado para testar a reprodutibilidade da técnica. A quantidade da perda mineral e a profundidade em que esta ocorreu foram analisadas em transversais traçadas em pontos eqüidistantes do limite esmalte normal-microabrasionado. Os dados obtidos foram analisados com o teste ANOVA (p < 0,05). RESULTADOS: A Técnica de Perfilometria obteve uma boa reprodutibilidade (coeficiente de correlação intraclasse de 0,9998) e foi validada internamente. O grupo AC foi o mais agressivo, apresentando a maior profundidade de desgaste (110,51 ± 41,21 &#956;m), e a maior perda mineral (13 ± 3 peso %), com diferenças significantes em relação aos grupos WRM (p < 0,05; 9,41± 4,4 peso %) e OP (p < 0,05; 9,0 ± 3,8 peso %). O grupo OP, por outro lado, foi o menos agressivo com os menores valores para todos os parâmetros analisados, apresentando uma profundidade de desgaste menor em relação aos grupos AC (p < 0,0001), WRM (p < 0,001; 86,24 ± 27,99 &#956;m) e AF (p < 0,05; 74,46 ± 42,06 &#956;m). Os outros dois grupos apresentaram resultados intermediários para profundidade de desgaste e quantidade de perda mineral. Não houve diferença quanto à profundidade de perda mineral CONCLUSÃO: Com base em uma terminologia própria para a interface esmalte normal-microabrasionado e na aplicação de uma nova Técnica de Perfilometria, os agentes testados mostraram uma significativa diferença quanto à profundidade de desgaste, que foi condizente com a perda mineral. A nova Técnica de Perfilometria propõe o preenchimento de uma lacuna na literatura, permitindo a determinação física de profundidade de desgaste em superfícies naturalmente curvas de tecidos biológicos duros

ANÁLISIS IN VITRO DE LA MICRO DUREZA DEL ESMALTE DENTAL HUMANO EXPUESTO AL PERÓXIDO CARBAMIDA Y SOMETIDO A LA ACCIÓN DEL FLUORETO

Este estudio analiz&oacute; la micro dureza del esmalte dental humano expuesto al agente blanqueador per&oacute;xido de carbamida a 16%, con posterior aplicaci&oacute;n, o no, de fluoreto de sodio a 2%. La muestra fue constituida por 20 dientes humanos, terceros molares inclusos de los cuales fueron confeccionados 20 espec&iacute;menes divididos en 2 grupos: Grupo A compuesto por 10 espec&iacute;menes que fueron clareados, GrupoB compuesto por 10 espec&iacute;menes clareados y sometidos a la aplicaci&oacute;n de fluoreto. Fueron tomadas lasmedidas iniciales y finales de micro dureza para los dos grupos. Despu&eacute;s del an&aacute;lisis estad&iacute;stico, los resultados demostraron que, para el Grupo A, el agente blanqueador no present&oacute; una reducci&oacute;nestad&iacute;sticamente significativa (p &lt; 0,05) en la micro dureza del esmalte dental, ya para el Grupo B, eluso de fluoreto de sodio a 2% restaur&oacute; completamente la micro dureza del esmalte. Se concluye que lat&eacute;cnica de blanqueamiento vital mediato con per&oacute;xido de carbamida a 16% es un tratamiento recomendado, pues aunque altere la micro dureza del esmalte, esa p&eacute;rdida es revertida probablemente debido al efecto tap&oacute;n de la saliva y al uso de fluoretos pos blanqueamiento.Abstract This study analyzed the microhardness of the human dental enamel exposed the brighten agent 16% carbamide peroxide, with and without application of 2% sodium flouride. The sample was established by twenty human tooth, intact third molars from which have been obtained twenty fractions of enamel andwere made the specimens, these have been divided in two groups : Group A - composed by 10 specimens which were only brighten, Group B - composed by ten specimens brighten and submitted on the application of flouride. After the initial results of microhardness of the dental enamel, were made the final measures of microhardness from the specimens from the Groups A and B. After statistical analysis,the results demonstrating that to the Group A, the brighten agent it didn&acute;t present a reduction significantestatistical (p &lt; 0,05) on microhardness of the dental enamel, about the group B the use of 2% sodium flouride revamped entirely the microhardness of the enamel. We concluded that the technique of mediate vital bleaching with 16% carbamide peroxide is a recommended treatment, because even it affects the&nbsp;microhardness of the enamel, this waste is probably reverted due the tampon effect from saliva and theuse of flouride after bleaching

Permeabilidade intestinal ao 51-CR-EDTA em ratos com cirrose induzida por tetracloreto de carbono (CCL4) : resultados preliminares

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