Effects of coronal substrates and water storage on the microhardness of a resin cement used for luting ceramic crowns

Composite resin and metallic posts are the materials most employed for reconstruction of teeth presenting partial or total destruction of crowns. Resin-based cements have been widely used for cementation of ceramic crowns. The success of cementation depends on the achievement of adequate cement curing. Objectives: To evaluate the microhardness of Variolink® II (Ivoclar Vivadent, Schaan, Liechtenstein), used for cementing ceramic crowns onto three different coronal substrate preparations (dentin, metal, and composite resin), after 7 days and 3 months of water storage. The evaluation was performed along the cement line in the cervical, medium and occlusal thirds on the buccal and lingual aspects, and on the occlusal surface. Material and Methods: Thirty molars were distributed in three groups (N=10) according to the type of coronal substrate: Group D- the prepared surfaces were kept in dentin; Groups M (metal) and R (resin)- the crowns were sectioned at the level of the cementoenamel junction and restored with metallic cast posts or resin build-up cores, respectively. The crowns were fabricated in ceramic IPS e.max® Press (Ivoclar Vivadent, Schaan, Liechtenstein) and luted with Variolink II. After 7 days of water storage, 5 specimens of each group were sectioned in buccolingual direction for microhardness measurements. The other specimens (N=5) were kept stored in deionized water at 37ºC for three months, followed by sectioning and microhardness measurements. Results: Data were first analyzed by three-way ANOVA that did not reveal significant differences between thirds and occlusal surface (p=0.231). Two-way ANOVA showed significant effect of substrates (

Evaluation of marginal sealing quality of restorations with low shrinkage composite resins

This study compared the quality of marginal sealing in the gingival wall of class II preparations of two low-shirinkage resins of the bulk fill type with a conventional resin isolated or associated with a glass ionomer cement (GIC). 40 human molars wer

Influence of the composition and shades of ceramics on light transmission and degree of conversion of dual-cured resin cements

Objective: Since the transmittance of ceramics can influence the degree of conversion (DC) of resin cements, ceramics composition and shade should be considered in the selection of resin cement. This in vitro study aimed to evaluate the effect of the transmittance of different composition, opacities and shades of ceramics on the degree of conversion of two dual-cured resin cements. Methodology: Sixty discs were prepared from low translucency (LT) and medium opacity (MO) lithium disilicate ceramic, and zirconia ceramic (Z). Each group was subdivided into 5 subgroups (n=4) in shades A2, A3.5, B2, C2 and D3. The transmittance measurement was performed in a spectrophotometer. The Variolink II and Rely X U200 resin cements were photoactivated by LED (1400 mW/cm2) for 40 s through the ceramic discs and without the discs (control group). The DC was measured with infrared FTIR spectroscopy, immediately after light activation. Data were analyzed with Kruskall-Wallis and one-way ANOVA, following post-hoc comparisons by Tukey test and Pearson’s correlation test (P<0.05). Results: LT ceramic exhibited higher transmittance values compared to MO and Z ceramics. LTA2 and LTB2 showed statistically higher transmittance values compared to MOA2, MOA3.5 and ZA3.5. For Variolink II, the ceramic interposition did not influence the DC, since there were no statistical differences between groups with ceramic interposition and the control group. For Rely X U200 cement, the interposition of some ceramics types/shades (LTA3.5, MOA2, MOA3.5 and ZA3.5) significantly decreased the DC values compared to control group. A positive correlation was found between the ceramic transmittance and DC values of both tested cements. Conclusions. The transmittance and DC values of the cements were influenced by composition and shades of the ceramics. The higher the transmittance of ceramics, the higher the DC values for both cements

Bilateral asymptomatic fibrous-ankylosis of the temporomandibular joint associated with rheumatoid arthritis: a case report

The American Academy of Orofacial Pain (AAOP) defines ankylosis of the temporomandibular joint (TMJ) as a restriction of movements due to intracapsular fibrous adhesions, fibrous changes in capsular ligaments (fibrous-ankylosis) and osseous mass formation resulting in the fusion of the articular components (osseous-ankylosis). The clinical features of the fibrous-ankylosis are severely limited mouth-opening capacity (limited range of motion during the opening), usually no pain and no joint sounds, marked deflection to the affected side and marked limitation of movement to the contralateral side. A variety of factors may cause TMJ ankylosis, such as trauma, local and systemic inflammatory conditions, neoplasms and TMJ infection. Rheumatoid arthritis (RA) is one of the systemic inflammatory conditions that affect the TMJ and can cause ankylosis. The aim of this study is to present a case of a female patient diagnosed with bilateral asymptomatic fibrous-ankylosis of the TMJ associated with asymptomatic rheumatoid arthritis. This case illustrates the importance of a comprehensive clinical examination and correct diagnosis of an unusual condition causing severe mouth opening limitation

A Companhia de Jesus na Índia e o Colégio de São Paulo em Goa: vicissitudes de 1552 a 1558

The Jesuit presence in the State of India dates back to 1542, when Francisco Xavier arrived in Goa. In 1548, the Jesuits founded the College of São Paulo, which became the reference center for the activities of the Society of Jesus in the East. The objective of this work is to discuss the College of São Paulo and the activities undertaken through it in the period between 1552 and 1558. In 1552 Francisco Xavier sets out on his mission to China, leaving Father Gaspar Barzeo in his place. Xavier's death still occurs in 1552 and that of Barzeo in 1553. After that, there is a period that we call in the work as a “command vacuum” in the Jesuit hierarchy in India, only remedied with the arrival of the new provincial and rector, in 1558. The sources used are contained in volumes II, III and IV of the Documenta Indica and in volume V of the Documentation for the history of the missions of the Portuguese Patronage of the East. It is concluded that the activities undertaken by these priests are, above all, cultural, religious and educational activities. Looking at these activities and their impacts on the local society at the time helps us to understand the dynamics of social and cultural interactions and power relations existing in the period studied. Key words: College of São Paulo. Company of Jesus. Goa. State of India. A presença jesuítica no Estado da Índia remonta ao ano de 1542, quando Francisco Xavier chega a Goa. Em 1548, os jesuítas fundam o Colégio de São Paulo, que passa a ser o centro referencial das atividades da Companhia de Jesus no Oriente. O objetivo deste artigo é versar sobre o Colégio de São Paulo e as atividades por meio dele empreendidas no período entre 1552 e 1558. Em 1552 Francisco Xavier sai em sua missão rumo à China, deixando em seu lugar o padre Gaspar Barzeo. A morte de Xavier ocorre ainda em 1552 e a de Barzeo em 1553. Depois disso, há um período que denominamos no trabalho como um “vazio de comando” na hierarquia jesuítica na Índia, apenas sanada com a chegada dos novos provincial e reitor, em 1558. A fontes utilizadas estão contidas nos volumes II, III e IV da Documenta Indica e no volume V da Documentação para a história das missões do Padroado português do Oriente. Conclui-se que as atividades empreendidas por estes padres são, sobretudo, atividades culturais, religiosas, educacionais. Olhar para tais atividades e seus impactos na sociedade local da época nos ajudam a compreender a dinâmica das interações sociais, culturais e das relações de poder existentes no período estudado.Palavras-chave: Colégio de São Paulo. Companhia de Jesus. Goa. Estado da Índia

Lesão Pulmonar Associada Ao Uso De Cigarros Eletrônicos: Revisão De Literatura

E-cigarettes, a widely used emerging product, are facing growing popularity despite little research into their health risks. Electronic Cigarette Use Associated Lung Injury, or EVALI, has become a prominent concern in recent research, expanding the need to understand the health effects of vaping, given the diversity of technologies and liquids involved. An integrative review was carried out to analyze the relationship between electronic cigarettes and lung injuries, using the PubMed database. 664 articles were selected, with inclusion criteria based on human studies published between 2018 and 2023. The analysis, exclusion and selection process was carefully conducted by the authors. Electronic cigarettes, consisting of a battery, atomizer and liquid, stand out due to the uncertainty about their health effects, in contrast to traditional cigarettes. EVALI, predominantly associated with the vaporization of THC products, reveals serious symptoms and significant risks. The complex composition of e-liquids, especially when exposed to high temperatures, generates harmful substances, including carbonyl compounds, suspected of causing oxidative stress and inflammation in the airways. The integrative review highlights the lack of consensus on the safety of electronic cigarettes and the urgency in understanding the associated risks. EVALI, as a diagnosis of exclusion, highlights the need for immediate investigation in the event of respiratory symptoms. Treatment and monitoring of EVALI patients requires a careful approach, considering clinical and risk factors. Public education about potential dangers and cessation strategies becomes crucial, especially among young people.Los cigarrillos electrónicos, un producto emergente ampliamente utilizado, se enfrentan a una creciente popularidad a pesar de la poca investigación sobre sus riesgos para la salud. La lesión pulmonar asociada al uso de cigarrillos electrónicos, o EVALI, se ha convertido en una preocupación destacada en investigaciones recientes, ampliando la necesidad de comprender los efectos del vapeo en la salud, dada la diversidad de tecnologías y líquidos involucrados. Se realizó una revisión integradora para analizar la relación entre los cigarrillos electrónicos y las lesiones pulmonares, utilizando la base de datos PubMed. Se seleccionaron 664 artículos, con criterios de inclusión basados ​​en estudios en humanos publicados entre 2018 y 2023. El proceso de análisis, exclusión y selección fue cuidadosamente realizado por los autores. Los cigarrillos electrónicos, compuestos por batería, atomizador y líquido, destacan por la incertidumbre sobre sus efectos sobre la salud, a diferencia de los cigarrillos tradicionales. EVALI, predominantemente asociado con la vaporización de productos de THC, revela síntomas graves y riesgos importantes. La compleja composición de los e-líquidos, especialmente cuando se exponen a altas temperaturas, genera sustancias nocivas, incluidos compuestos carbonílicos, sospechosos de causar estrés oxidativo e inflamación en las vías respiratorias. La revisión integradora destaca la falta de consenso sobre la seguridad de los cigarrillos electrónicos y la urgencia de comprender los riesgos asociados. EVALI, como diagnóstico de exclusión, destaca la necesidad de investigación inmediata en caso de síntomas respiratorios. El tratamiento y seguimiento de los pacientes con EVALI requiere un enfoque cuidadoso, considerando los factores clínicos y de riesgo. La educación pública sobre los peligros potenciales y las estrategias para dejar de fumar se vuelve crucial, especialmente entre los jóvenes.Os cigarros eletrônicos, produto emergente amplamente utilizado, enfrentam crescente popularidade apesar da escassa investigação sobre seus riscos à saúde. A Lesão Pulmonar Associada ao Uso de Cigarro Eletrônico, ou EVALI, tornou-se uma preocupação destacada nas pesquisas recentes, ampliando a necessidade de compreender os efeitos da vaporização na saúde, dada a diversidade de tecnologias e líquidos envolvidos. Realizou-se uma revisão integrativa para analisar a relação entre cigarros eletrônicos e lesões pulmonares, utilizando a base de dados PubMed. Foram selecionados 664 artigos, com critérios de inclusão baseados em estudos humanos publicados entre 2018 e 2023. O processo de análise, exclusão e seleção foi conduzido de forma criteriosa pelos autores. Os cigarros eletrônicos, compostos por bateria, atomizador e líquido, destacam-se pela incerteza sobre seus efeitos à saúde, em contraste com os tradicionais. A EVALI, predominantemente associada à vaporização de produtos com THC, revela sintomas graves e riscos significativos. A composição complexa dos e-líquidos, especialmente quando expostos a altas temperaturas, gera substâncias nocivas, incluindo compostos carbonílicos, suspeitos de causar estresse oxidativo e inflamação nas vias aéreas. A revisão integrativa destaca a falta de consenso sobre a segurança dos cigarros eletrônicos e a urgência em compreender os riscos associados. A EVALI, como diagnóstico de exclusão, destaca a necessidade de investigação imediata diante de sintomas respiratórios. O tratamento e o acompanhamento de pacientes EVALI requerem abordagem cuidadosa, considerando fatores clínicos e de risco. A educação pública sobre os perigos potenciais e estratégias de cessação torna-se crucial, especialmente entre os jovens

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

Effect of ceramic composition and shade in light transmission and degree of conversion of dual-cure resin cements

O objetivo desta pesquisa foi avaliar a transmitância de diferentes tipos e cores de cerâmicas e seus efeitos no grau de conversão (GC) de dois tipos de cimentos resinosos com modo de polimerização dual. Foram confeccionadas 60 pastilhas com a cerâmica IPS e.max (Ivoclar Vivadent, Schaan, Liechtenstein) e divididas em 3 grupos: LT, MO e Z, com 20 pastilhas cada um. Nos grupos LT e MO, as pastilhas foram confeccionadas com a cerâmica de dissilicato de lítio de baixa translucidez (LT - low transluscency) e de média opacidade (MO - medium opacity), respectivamente. No grupo Z, as pastilhas foram confeccionadas em zircônia. Cada grupo foi subdividido em 5 subgrupos (n=4), de acordo com a cor da cerâmica: A2; A3,5; B2; C2; D3. No grupo LT, as pastilhas foram prensadas nas cores anteriormente citadas e, nos grupos MO e Z, as pastilhas foram, inicialmente, confeccionadas para simular infraestruturas e, posteriormente, receberem aplicação de cerâmica de revestimento IPS e.max Ceram (Ivoclar Vivadent, Schaan, Liechtenstein) nas mesmas cores. O espectrofotômetro UV 1800 Shimadzu foi utilizado para medir a transmitância de cada espécime de cerâmica (2,0 mm de espessura). Para medir o GC, espécimes dos cimentos resinosos Variolink II (Ivoclar Vivadent, Schaan, Liechtenstein) e Rely X U200 (3M ESPE, St. Paul, MN, USA), com espessura de 100 μm, foram fotopolimerizados sob os discos de cerâmica por 40 s. Espécimes dos cimentos fotoativados sem a interposição da cerâmica foram usados como grupo controle. A polimerização dos cimentos foi avaliada através da espectrometria no infravermelho com transformada de Fourier (FTIR) empregando o método de reflexão atenuada total (ATR) imediatamente após a fotopolimerização. Os resultados foram submetidos aos testes ANOVA a 1 critério e Teste de Tukey (α=5%). Os valores de transmitância foram inferiores a 1%, sendo que as do grupo LT apresentaram, em geral, os maiores valores de transmitância, seguidos dos grupos MO e Z. O GC do cimento Variolink II não sofreu influência da interposição da pastilha de cerâmica. Para o cimento Rely X U200, a interposição de alguns tipos/cores de cerâmica (LT A3,5; MO A2; MO A3,5 e Z A3,5) diminuíram o GC em relação ao grupo controle. Concluiu-se que os valores de transmitância e GC foram influenciados pelos tipos/cores de cerâmica. Entretanto, somente o grupo formado pela cerâmica de dissilicato de lítio LT, usando o Rely X U200, apresentou correlação negativa entre transmitância e GC.The aim of the present study was to evaluate the transmittance of different ceramic types and shades and their effects on the degree of conversion (DC) of two dual-cure resin cements. Sixty discs were fabricated with IPS e.max ceramic (Ivoclar Vivadent, Schaan, Liechtenstein) and divided into three groups (n= 20 in each group): LT, MO and Z. For LT and MO groups discs were fabricated with low translucency (LT) and medium opacity (MO) lithium disilicate ceramic, respectively. Discs from Z group were manufactured of zirconia. Each group was divided into five subgroups (n = 4), according to the ceramic shade: A2; A3,5; B2; C2; D3. In the LT group, specimens were heat-pressed in shades cited above and in the MO and Z groups, the discs were initially fabricated as core materials and then veneered with veneer ceramic (IPS e.max Ceram, Ivoclar Vivadent, Schaan, Liechtenstein) in the same shades. A spectrophotometer UV-1800 Shimadzu was used to determine the transmittance percentage of each ceramic specimen (2.0-mm-thick). For DC measurements, the resin cements (Variolink II - Ivoclar Vivadent, Schaan, Liechtenstein and Rely X U200 - 3M ESPE, St. Paul, MN, USA) specimens (thickness: 100 μm) were photocured under the ceramic discs (2.0-mm-thick) for 40 s. Specimens photocured without the ceramics discs were used as control group. ATR/FTIR spectrometry was used to evaluated the extent of polymerization for all cement specimens immediately after photocuring. The results were submitted to one-way ANOVA and Tukey test (α=5%). The transmittance percentage was less than 1% and the LT group had the highest transmittance values, followed by MO and Z groups. The %DC of Variolink II cement was not influenced by the ceramic disc interposition. For Rely X U200 cement, the interposition of some ceramics types/shades (LT A3,5, MO A2, MO A3,5 and Z A3,5) significantly decreased the %DC compared to control group. It was concluded that the transmittance values and %DC were influenced by the ceramics types/shades. However, only the LT group, using the Rely X U200, showed a negative correlation between transmittance and %DC