Effect of deproteinization and tubular occlusion on microtensile bond strength and marginal microleakage of resin composite restorations

Dentin adhesion procedure presents limitations, especially regarding to lifetime stability of formed hybrid layer. Alternative procedures have been studied in order to improve adhesion to dentin. OBJECTIVE: The aim of this study was to evaluate in vitro the influence of deproteinization or dentin tubular occlusion, as well as the combination of both techniques, on microtensile bond strength (µTBS) and marginal microleakage of composite resin restorations. MATERIAL AND METHODS: Extracted erupted human third molars were randomly divided into 4 groups. Dentin surfaces were treated with one of the following procedures: (A) 35% phosphoric acid gel (PA) + adhesive system (AS); (B) PA + 10% NaOCl + AS; (C) PA + oxalate + AS and (D) PA + oxalate + 10% NaOCl + AS. Bond strength data were analyzed statistically by two-way ANOVA and Tukey's test. The microleakage scores were analyzed using Kruskal-Wallis and Mann-Whitney non-parametric tests. Significance level was set at 0.05 for all analyses. RESULTS: µTBS data presented statistically lower values for groups D and B, ranking data as A>C>B>D. The use of oxalic acid resulted in microleakage reduction along the tooth/restoration interface, being significant when used alone. On the other hand, the use of 10% NaOCl alone or in combination with oxalic acid, resulted in increased microleakage. CONCLUSIONS: Dentin deproteinization with 10% NaOCl or in combination with oxalate significantly compromised both the adhesive bond strength and the microleakage at interface. Tubular occlusion prior to adhesive system application seems to be a useful technique to reduce marginal microleakage

MANEJO DE PACIENTES HEMOFÍLICOS NA CLÍNICA ODONTOLÓGICA - UMA REVISÃO INTEGRATIVA DA LITERATURA

Abstract: Hemophilia is a genetic condition in which there are changes in the quantity and quality of plasma proteins that act in the blood clotting processes in a hereditary way. Objective: to carry out a scientific survey in the current literature on the management of hemophiliac patients in the dental clinic, highlighting aspects of the theme that answered the guiding question of the integrative review. Methodology: A literature search was carried out through the electronic database PubMed, using the search keywords, “MeSHterm”: “Hemophilia” AND “Dentistry”. The articles were evaluated according to the pre-established inclusion and exclusion criteria and the Boolean connector “AND” was used. Results and Discussion: Therefore, based on this search strategy, of the 20 articles that met the criteria, only 10 were selected to compose the study, as 10 articles did not address dental management in hemophiliac patients. Therefore, the dental management of hemophiliac patients is centered on hemostasis of the surgical field and on the administration of coagulation factors that are deficient according to the type of hemophilia. Final Considerations: Furthermore, as this is a disease that can involve systemic involvement, it is important to have a multidisciplinary approach, including dentists, hematologists and oral surgeons. Therefore, this integrative literature review included a detailed analysis of 10 articles, focusing on the dental management of hemophiliac patients. The results obtained successfully answered the research's guiding question.Resumen: La hemofilia es una condición genética en la que se producen cambios en la cantidad y calidad de las proteínas plasmáticas que actúan en los procesos de coagulación sanguínea de forma hereditaria. Objetivo: realizar un relevamiento científico en la literatura actual sobre el manejo de pacientes hemofílicos en la clínica dental, destacando aspectos de la temática que respondieron a la pregunta orientadora de la revisión integradora. Metodología: Se realizó una búsqueda bibliográfica a través de la base de datos electrónica PubMed, utilizando las palabras clave de búsqueda, “MeSHterm”: “Hemofilia” Y “Odontología”. Los artículos fueron evaluados según los criterios de inclusión y exclusión preestablecidos y se utilizó el conector booleano “Y”. Resultados y Discusión: Por lo tanto, con base en esta estrategia de búsqueda, de los 20 artículos que cumplieron con los criterios, solo 10 fueron seleccionados para componer el estudio, ya que 10 artículos no abordaron el manejo dental en pacientes hemofílicos. Por tanto, el manejo odontológico de los pacientes hemofílicos se centra en la hemostasia del campo quirúrgico y en la administración de factores de coagulación deficientes según el tipo de hemofilia. Consideraciones finales: Además, dado que se trata de una enfermedad que puede implicar afectación sistémica, es importante tener un abordaje multidisciplinario, incluyendo dentistas, hematólogos y cirujanos orales. Por lo tanto, esta revisión integradora de la literatura incluyó un análisis detallado de 10 artículos, enfocándose en el manejo dental de pacientes hemofílicos. Los resultados obtenidos respondieron con éxito a la pregunta orientadora de la investigación.Resumo: A hemofilia é uma condição genética em que ocorre alterações na quantidade e qualidade de proteínas plasmáticas que atuam nos processos de coagulação sanguínea de forma hereditária. Objetivo: fazer um levantamento científico na literatura atual sobre o manejo de pacientes hemofílicos na clínica odontológica, evidenciando aspectos da temática que respondessem à pergunta norteadora da revisão integrativa. Metodologia: Foi realizada uma busca da literatura através da base de dados eletrônicas PubMed, utilizando as palavras-chave para pesquisa, “MeSHterm”: “Hemophilia” AND “Dentistry”. Os artigos foram avaliados quanto aos critérios de inclusão e exclusão pré-estabelecidos e utilizou-se do conector booleano “AND’’. Resultados e Discussão: Portanto, a partir dessa estratégia de busca, dos 20 artigos que se adequaram aos critérios, apenas 10 foram selecionados para compor o estudo, já que 10 artigos não abordavam o manejo odontológico frente aos pacientes hemofílicos. Sendo assim, o manejo odontológico dos pacientes hemofílicos é centrado na hemostasia do campo cirúrgico e na administração de fatores de coagulação que se apresentam deficientes de acordo com o tipo de hemofilia. Considerações Finais: Ademais, por se tratar de uma doença que pode envolver comprometimento sistêmico, é importante que haja uma abordagem multidisciplinar incluindo dentistas, hematologistas e cirurgiões orais. Logo, a presente revisão integrativa de literatura contou com a análise detalhada de 10 artigos, com enfoque no manejo odontológico de pacientes hemofílicos. Os resultados obtidos responderam com êxito a pergunta norteadora da pesquisa

Effect of propolis gel on the in vitro reduction of dentin permeability

OBJECTIVE: The aim of this study was to evaluate the capacity of potassium oxalate, fluoride gel and two kinds of propolis gel to reduce the hydraulic conductance of dentin, in vitro. MATERIAL AND METHODS: The methodology used for the measurement of hydraulic conductance of dentin in the present study was based on a model proposed in literature. Thirty-six 1-mm-thick dentin discs, obtained from extracted human third molars were divided into 4 groups (n=9). The groups corresponded to the following experimental materials: GI-10% propolis gel, pH 4.1; GII-30% propolis gel; GIII-3% potassium oxalate gel, pH 4,1; and GIV-1.23% fluoride gel, pH 4.1, applied to the dentin under the following surface conditions: after 37% phosphoric acid and before 6% citric acid application. The occluding capacity of the dentin tubules was evaluated using scanning electron microscopy (SEM) at ×500, ×1,000 and ×2,000 magnifications. Data were analyzed statistically by two-way ANOVA and Tukey's test at 5% significance level. RESULTS: Groups I, II, III, IV did not differ significantly from the others in any conditions by reducing in hydraulic conductance. The active agents reduced dentin permeability; however they produced the smallest reduction in hydraulic conductance when compared to the presence of smear layer (P<0.05). The effectiveness in reducing dentin permeability did not differ significantly from 10% or 30% propolis gels. SEM micrographs revealed that dentin tubules were partially occluded after treatment with propolis. CONCLUSIONS: Under the conditions of this study, the application of 10% and 30% propolis gels did not seem to reduce the hydraulic conductance of dentin in vitro, but it showed capacity of partially obliterating the dentin tubules. Propolis is used in the treatment of different oral problems without causing significant great collateral effects, and can be a good option in the treatment of patients with dentin sensitivity

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

Rock n' Seeds: A database of seed functional traits and germination experiments from Brazilian rock outcrop vegetation

Advancing functional ecology depends fundamentally on the availability of data on reproductive traits, including those from tropical plants, which have been historically underrepresented in global trait databases. Although some valuable databases have been created recently, they are mainly restricted to temperate areas and vegetative traits such as leaf and wood traits. Here, we present Rock n' Seeds, a database of seed functional traits and germination experiments from Brazilian rock outcrop vegetation, recognized as outstanding centers of diversity and endemism. Data were compiled through a systematic literature search, resulting in 103 publications from which seed functional traits were extracted. The database includes information on 16 functional traits for 383 taxa from 148 genera, 50 families, and 25 orders. These 16 traits include two dispersal, six production, four morphological, two biophysical, and two germination traits-the major axes of the seed ecological spectrum. The database also provides raw data for 48 germination experiments, for a total of 10,187 records for 281 taxa. Germination experiments in the database assessed the effect of a wide range of abiotic and biotic factors on germination and different dormancy-breaking treatments. Notably, 8255 of these records include daily germination counts. This input will facilitate synthesizing germination data and using this database for a myriad of ecological questions. Given the variety of seed traits and the extensive germination information made available by this database, we expect it to be a valuable resource advancing comparative functional ecology and guiding seed-based restoration and biodiversity conservation in tropical megadiverse ecosystems. There are no copyright restrictions on the data; please cite this paper when using the current data in publications; also the authors would appreciate notification of how the data are used in publications