40 research outputs found

    Fibromatose gengival: revisão de literatura/Gingival fibromatosis: a literature review

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     A fibromatose gengival é uma condição rara, caracterizada pelo aumento lento e progressivo do tecido gengival. Essa condição pode gerar dificuldades na fala, mastigação, oclusão, selamento labial e aparência facial. Além de diastemas, má posição dentária, retenção prolongada dos dentes decíduos e atraso da erupção dos dentes permanentes. O objetivo deste estudo foi realizar uma revisão da literatura sobre a fibromatose gengival com descrição de vários tópicos, tais como a prevalência, a caracterização clínica e histopatológica, o diagnóstico, a etiopatogenia e as opções de tratamento relacionando-se a um protocolo de abordagem a pacientes em tratamento ortodôntico. Diante das alterações fisiopatológicas que essa condição causa, compreende-se a relevância da intervenção de uma equipe multidisciplinar. Embora limitações estéticas e funcionais estejam presentes, é possível que se promova uma melhor qualidade de vida desses pacientes. Entretanto, na literatura há falta de evidência de estudos clínicos associados à ortodontia em indivíduos afetados por esta condição

    Disinfection of Orthodontic Elastomers and Its Effects on Tensile Strength

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    Objective: This study aimed to investigate the effect of different disinfection protocols on the mechanical properties of orthodontic elastomeric ligatures (EL), an important issue to biosafety improvement and infection control, and to avoid cross-contamination.Methods: A total of 120 EL were randomly divided into 6 experimental groups (n = 20) according to the disinfection method employed: group 1, EL were not immersed in a disinfectant solution (control group); group 2, EL were immersed in 2% glutaraldehyde; group 3, EL were immersed in 70% alcohol solution; group 4, EL were cleaned in an ultrasound washing (UW) machine by immersion in 0.5% enzyme detergent solution; group 5, UW procedure was performed, followed by immersion in 2% glutaraldehyde; Group 6, UW procedure was performed, followed by immersion in 70% alcohol. After disinfection, EL were subjected to a tensile strength test where the maximum strength, maximum elongation, and work at failure were determined. Data were statistically evaluated using one-way ANOVA and Dunnett’s t-test for multiple comparisons.Results:Statistically significant different (P < .05) values were found between the disinfection methods, and 70% alcohol showed negative changes in all mechanical properties of orthodontic elastomers. By contrast, 2% glutaraldehyde did not show significant alteration in mechanical properties, whereas the UW procedure showed significant alteration in maximum strength and work at failure.Conclusion:Of the tested substances for disinfection, 2% glutaraldehyde was the only substance that did not cause significant changes in the mechanical properties of orthodontic elastics and is considered as an alternative for elastic disinfection before its use

    Pervasive gaps in Amazonian ecological research

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    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

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    Pervasive gaps in Amazonian ecological research

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    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

    Pervasive gaps in Amazonian ecological research

    Get PDF
    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 comparativa da expansão maxilar com três marcas de parafusos com limitador posterior: ensaio laboratorial em Typodont Comparative analysis of rapid maxillary expansion using three brands of fan-type expander screw: laboratory trial using typodont

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    INTRODUÇÃO: nos pacientes com fissura labiopalatina, observa-se, usualmente, uma severa atresia da maxila, especialmente na região anterior da arcada, cujo tratamento envolve expansão maxilar. OBJETIVO: o propósito desse estudo foi avaliar o padrão de expansão de três marcas de parafusos com limitador posterior na correção da deficiência transversa. MÉTODOS: foram realizadas 18 expansões em Typodont, com 6 simulações para cada grupo: G1 - parafuso Dentaurum®, G2 - parafuso Leone®, e G3 - parafuso Morelli®. Foram realizadas, para cada ensaio, 13 ativações de 2/4 de volta, totalizando 5,2mm de abertura do parafuso. Definiram-se os momentos das medições em inicial (T1), metade das ativações (T2) e final (T3). Com o auxílio de um paquímetro, foram medidas as seguintes distâncias: interprimeiros pré-molares (IP1), interssegundos pré-molares (IP2), intermolares (IM) e comprimento da arcada (CA). Os dados obtidos foram submetidos aos testes de Kolmogorov-Smirnov, de Tukey, de Friedman e ANOVA. RESULTADOS: observou-se que todos os grupos apresentaram um padrão de abertura em forma de "V" com maior expansão na região anterior da arcada, sendo mais expressivo no grupo G3 (29,58% em IP1 e 9,73% em IM). O aumento na medida CA foi semelhante para os grupos G1 e G3 (+12,65% e +12,13%, respectivamente), com menor valor para o G2 (+8,23%). CONCLUSÕES: concluiu-se que todos os parafusos com limitador posterior utilizados nesse estudo podem ser empregados no tratamento da deficiência transversa da arcada. Entretanto, o parafuso Morelli® apresentou maior abertura na região anterior em relação à posterior, característica importante no tratamento de pacientes com fissura labiopalatina. Recomenda-se a realização de estudos clínicos para confirmação desses achados.<br>INTRODUCTION: Severe constriction of the maxillary arch, especially in the anterior part of the maxilla, is a common finding in cleft lip and palate patients. The usual treatment generally involves the expansion of the arch. OBJECTIVE: The aim of this study was to evaluate the expansion pattern obtained with three different fan-type expander screws. METHODS: Using Typodont, 18 expansions were executed, six for each group, according to the expander tested: G1- DentaurumTM; G2- LeoneTM and G3- MorelliTM. For each essay, 13 activations of 2/4 of a turn were done in each appliance, leading to a total activation of 5.2mm. Using a caliper, measurements were taken in the beginning of the testing (T1); in half the total turnings (T2) and in the end of the testing (T3). Different measures were considered: interpremolar width (IP1), intersecond premolar width (IP2), intermolar width (IM) and also the arch length (CA). The data obtained was analyzed through Kolmogorov-Smirnov, Tukey and Freeman tests as well as by ANOVA. RESULTS: It could be observed that all tested groups showed a "V" expansion pattern, with major expansion in the anterior region of the arch, that was even more expressive in G3 (IP1=29.85% and IM=9.73%). Increases in the CA measurements were similar for groups G1 and G3 (+12.65% and +12.13%, respectively), and lower for G2 (+8.23%). CONCLUSIONS: It could be concluded that all the fan-type expander screws tested in the present study can be used for treating transverse constriction of the maxilla. However, Morelli expander showed a greater expansion in the anterior region of the arch in relation to the posterior region, which is an important characteristic when treating cleft lip and palate patients. Clinical studies are also necessary to confirm the findings of the present study
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