Orientador: Mario Tanomaru Filho / Banca: Milton Carlos Kuga / Banca: Fábio Luiz Camargo Villela Berbet / Banca: Celso Luiz Caldeira / Banca: Ivaldo Gomes de Moraes / Resumo: O objetivo deste estudo foi avaliar a capacidade de preenchimento de canais laterais simulados pela guta-percha e Resilon, empregando diferentes técnicas termoplastificadoras de obturação: Condensação Vertical Aquecida (CVA), Compactação Termomecânica (CT) e Sistema Obtura II (SO). Foram utilizados 135 dentes humanos unirradiculados extraídos. Após preparo biomecânico, foram confeccionados seis canais laterais simulados em suas raízes, de acordo com a técnica proposta por Venturi et al. (2005). O diâmetro desses canais foi correspondente aos instrumentos # 08 e 10, sendo estabelecidos a 2, 5 e 8 mm do comprimento de trabalho (CT). Os espécimes foram divididos em 9 grupos (n=15), sendo: Grupo I (CVA + guta-percha Dentsply), Grupo II (CVA + Resilon), Grupo III (CVA + guta-percha Odous), Grupo IV (CT + guta-percha Dentsply), Grupo V (CT + Resilon), Grupo VI (CT + guta-percha Odous), Grupo VII (SO + guta-percha Obtura Flow 150), Grupo VIII (SO + Resilon) e Grupo IX (SO + guta-percha Odous Flow). Após a realização das obturações, os espécimes foram analisados pelos métodos radiográfico e diafanização, em função do percentual de preenchimento nos canais laterais, nos três terços. Os resultados foram submetidos ao teste de Kruskal-Wallis, com 5% de nível de significância, de acordo com avaliações específicas intra-grupos: CVA (Grupos I, II e III), CTH (Grupos IV, V e VI), SO (Grupos VII, VIII e IX) e Resilon (Grupos II, V e VIII). As avaliações CVA e CTH mostraram que o Resilon apresentou maior capacidade de preenchimento nas duas análises, em relação aos demais materiais, nos terços apical e médio (p<0,05). Quanto à avaliação SO, todos os materiais apresentaram boa capacidade de preenchimento dos canais laterais em todos os terços, com exceção do terço cervical onde o Resilon foi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the ability of gutta-percha and Resilon to fill simulated canals using different thermoplastic obturation techniques: Warm Vertical Compaction (CVA), Thermomechanical Compaction (CTE) and Obtura II System (SO). It was used 135 extracted human teeth uniradicular. After biomechanical preparation, six simulated lateral canals were prepared in the roots, according to the technique proposed by Venturi et al. (2005). The diameter of these canals was equivalent to # 08 and 10 instruments and are set at 2, 5 and 8 mm to working length (WL). The specimens were divided into nine groups (n=15), as follow: Group I (CVA + gutta-percha Denstply), Group II (CVA + Resilon), Group III (CVA + gutta-percha Odous), Group IV (CTE + gutta-percha Dentsply), Group V (CTE + Resilon), Group VI (CTE + gutta-percha Odous), Group VII (SO + gutta-percha Obtura Flow 150), Group VIII (SO + Resilon) and Group IX (SO + gutta-percha Odous Flow). After the obturation, the samples were analyzed by radiographic and clearing methods, according to percentage of filling the lateral canals, in the three thirds. The result were submitted to the Kruskal-Wallis test at 5% significance level, according to specific intra-group evaluations: CVA (Groups I, II and III), CTH (Groups IV, V and VI), SO (Groups VII, VIII and IX) and Resilon (Groups II, V and VIII). CVA and CTH assessments showed that the Resilon has great ability to fill lateral canals in the two tests, compared to the other materials, in the apical and middle thirds (p < 0.05). As for SO evaluation, all materials showed good filling capacity of the lateral canals in all thirds, except in the cervical third where Resilon was better by radiographic analysis (extension and area) and in the cervical and middle thirds for clearing analysis (extension)... (Complete abstract click electronic access below) / Doutor

Enhanced mass transport in carbon-based nanoscale conduits (e.g. carbon nanotubes, graphene nanochannels/capillaries, graphene/graphene oxide membranes) has attracted tremendous interest over the last decade due to its significant implications for water desalination/purification, nanofiltration, electronic cooling, battery/fuel cells, and lab-on-a-chip. Further development of carbon-based nanoscale conduits for practical applications relies on understanding fundamental mechanisms of transport through individual conduits, which have not been well studied due to challenges in fabrication and measurement. In this thesis, the construction of two-dimensional planar graphene nanochannel devices and the studies of enhanced water and ion transport inside the graphene nanochannels are reported for the first time. The graphene nanochannels are fabricated by conformally covering high-quality graphene on the surfaces of silica nanochannels. A new fabrication scheme consisting of graphene wet transfer, graphene patterning and vacuum anodic bonding is developed to create such graphene nanochannels with heights ranging from 24 to 124 nm. Using these nanochannels and a new hybrid nanochannel based capillary flow measurement technique, we successfully measured the hydraulic resistance (water permeability) of single graphene nanochannels. Our results demonstrate that the frictionless surface of graphene induces a boundary slip and enhances water flow inside the graphene nanochannel. The measured slip length of graphene in the graphene nanochannels poses a median value around 16 nm, albeit with a large variation from 0 to 200 nm regardless of the channel height. The small-yet-widely-varying values of the graphene slip length are attributed to the surface charge of graphene and the interaction between graphene and underneath silica substrate, which are in good agreement with the prediction of our molecular dynamics (MD) simulation. In addition, we also investigated enhanced ion transport inside the graphene nanochannels. Higher electroosmotic conductance at low electrolyte concentrations (10-6 M~10-2 M) is observed in graphene nanochannels when compared with silica nanochannels with the same geometry. Our results suggest that the enhanced electroosmotic flow is also due to the boundary slip at the graphene/electrolyte interface. Besides, our analysis shows that the surface charge on the graphene, originating from the dissociation of oxygen-containing functional groups, is crucial to the enhanced electroosmotic flow inside nanochannels.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-08-08T20:51:33Z No. of bitstreams: 1 LEYDSON GALVÍNCIO DANTAS – DISSERTAÇÃO (PPGMET) 2016.pdf: 2738181 bytes, checksum: db3cee5c7f083124e00eb4eb3220492c (MD5) / Made available in DSpace on 2018-08-08T20:51:33Z (GMT). No. of bitstreams: 1 LEYDSON GALVÍNCIO DANTAS – DISSERTAÇÃO (PPGMET) 2016.pdf: 2738181 bytes, checksum: db3cee5c7f083124e00eb4eb3220492c (MD5) Previous issue date: 2016-02-19 / CNPq / A variabilidade espacial e temporal das precipitações no estado da Paraíba, proporciona irregularidades na distribuição da mesma, como frequentemente observado nos eventos de secas prolongadas e excesso de precipitação em intervalos curtos de tempo, comprometendo em termos gerais a qualidade de vida da população. Neste trabalho é elaborado o preenchimento das falhas encontradas nas séries temporais em alguns municípios do Estado, obtendo deste modo, uma séria robusta o bastante, na qual tem a função de auxiliar, as análises dos resultados ao ser trabalhada com a metodologia de Box-Jenkins para séries temporais. Visando assim, a elaboração de prognósticos pluviométricos em algumas cidades do Estado por intermédio de modelos estocásticos, onde nota-se que a forma do modelo SARIMA(1,0,1)×(1,1,1) é o que melhor se ajusta pela análise dos critérios e resíduos, dentre os municípios onde as previsões chegaram a equivaler alguns dos valores observados nas estações pluviométricas. Os municípios localizados nas proximidades do Planalto da Borborema foram os que demonstraram a melhor acurácia em termos de previsibilidade ao ser comparado com os outros analisados neste estudo. / The spatial and temporal variability of rainfall in the state of Paraiba, provides irregularities in the distribution of the same, as often observed in prolonged droughts events and excess rainfall in short time intervals, affecting generally the quality of life of the population. This paper prepared filling the gaps found in the time series in some cities of the State, thereby obtaining a robust serious enough, which has a helper function, the analysis of the results to be crafted with the Box-Jenkins methodology for time series. Aiming thus the development of rainfall predictions in some cities of the State through stochastic models, where it is noted that the model shape SARIMA(1,0,1)×(1,1,1) is the best fit for analysis the criteria and waste from the municipalities where the predictions come to equate some of the values observed in the rainfall stations. The Cities located near of the Planalto of Borborema were the ones that showed the best accuracy in terms of predictability when compared to the other analyzed in this study.

Latin hypercube designs (LHDs) have broad applications in constructing computer experiments and sampling for Monte-Carlo integration due to its nice property of having projections evenly distributed on the univariate distribution of each input variable. The LHDs have been combined with some commonly used computer experimental design criteria to achieve enhanced design performance. For example, the Maximin-LHDs were developed to improve its space-filling property in the full dimension of all input variables. The MaxPro-LHDs were proposed in recent years to obtain nicer projections in any subspace of input variables. This thesis integrates both space-filling and projection characteristics for LHDs and develops new algorithms for constructing optimal LHDs that achieve nice properties on both criteria based on using the Pareto front optimization approach. The new LHDs are evaluated through case studies and compared with traditional methods to demonstrate their improved performance.

Esta dissertação investiga soluções para o problema genérico de geração de vistas sintéticas a partir de um conjunto de imagens utilizando a abordagem Depth-Image-Based Rendering. Essa abordagem utiliza um formato compacto para a representação de imagens 3D, composto basicamente por duas imagens, uma colorida para a vista de referência e outra em tons de cinza com a correspondência de disparidade para cada pixel. Soluções para esse problema beneficiam aplicações como Free Viewpoint Television. O maior desafio é o preenchimento de regiões sem informação de projeção considerando o novo ponto de vista, genericamente denominados holes, além de outros artefatos como cracks e ghosts que ocorrem por oclusões e erros no mapa de disparidade. Nesta dissertação apresentamos técnicas para remoção e tratamento de cada uma das classes de potenciais artefatos. O conjunto de métodos propostos apresenta melhores resultados quando comparado com o atual estado da arte em geração de vistas sintéticas com o modelo DIBR para o conjunto de dados Middlebury, considerando-se as métricas SSIM e PSNR. / This dissertation investigates solutions to the general problem of generating synthetic views from a set of images using the Depth-Image-Based Rendering approach. This approach uses a compact format for the 3D image representation, composed basically of two images, one color image for the reference view and other grayscale image with the disparity information available for each pixel. Solutions to this problem benefit applications such as Free Viewpoint Television. The biggest challenge is filling in regions without projection information considering the new viewpoint, usually called holes, and other artifacts such as cracks and ghosts that occur due to occlusions and errors in the disparity map. In this dissertation we present techniques for removal and treatment of each of these classes of potential artifacts. The set of proposed methods shows improved results when compared to the current state of the art generation of synthetic views using the DIBR model applied to the Middlebury dataset, considering the SSIM and PSNR metrics.

Muitas informações disponíveis na Web estão armazenadas em bancos de dados on-line e são acessíveis somente após um usuário enviar uma consulta por meio de uma interface de busca. Essas informações estão localizadas em uma parte da Web conhecida como Web Oculta ou Web Profunda e, geralmente, são inacessíveis por máquinas de busca tradicionais. Uma vez que a forma de acessar os dados na Web Oculta se dá por intermédio de submissões de consultas, muitos trabalhos têm focado em como preencher automaticamente campos de formulários. Esta tese apresenta uma metodologia para o preenchimento de formulários na Web Oculta. Além disso, descreve uma categorização das técnicas de preenchimento de formulários existentes no estado da arte de coleta na Web Oculta, produzindo uma análise comparativa entre elas. A solução proposta descreve um método automático para seleção de valores para campos de formulários combinando heurísticas e técnicas de aprendizagem de máquina. Experimentos foram realizados em formulários reais da Web, de vários domínios, e os resultados indicam que a abordagem proposta apresenta desempenho comparável aos obtidos pelas técnicas do estado da arte, sendo inclusive significativamente diferente com base em avaliação estatística. / A large portion of the information on the Web is stored inside online databases. Such information is accessible only after the users submit a query through a search interface. TheWeb portion in which that information is located is called HiddenWeb or DeepWeb, and generally this part is inaccessible by traditional search engines crawlers. Since the only way to access the Hidden Web pages is through the query submissions, many works have focused on how to fill in form fields automatically, aiming at enhancing the amount of distinct information hidden behind Web forms. This thesis presents an automatic solution to value selection for fields in Web forms. The solution combines heuristics and machine learning techniques for improving the selection of values. Furthermore, this proposal also describes a categorization of form filling techniques and a comparative analysis between works in the state of the art. Experiments were conducted on real Web sites and the results indicated that our approach significantly outperforms a baseline method in terms of coverage without additional computational cost.

Made available in DSpace on 2014-06-11T19:31:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-04-30Bitstream added on 2014-06-13T20:02:13Z : No. of bitstreams: 1 souza_em_dr_arafo.pdf: 523065 bytes, checksum: 1f16938a629ebc74f2bcba8ab193a12c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Diferentes técnicas de compactação da guta-percha (GP) e cimentos oburadores podem alterar a qualidade final da obturação do canal radicular. Recentemente foi introduzido um novo modelo de análise da qualidade de obturações endodônticas baseado na mensuração da concentração da glicose que passa pela falha na obturação. Este trabalho é composto por três capítulos cujos objetivos foram: a) determinar os efeitos de variações na técnica de condensação lateral (LC) e da área do canal na qualidade da obturação; b) verificar se diferentes materiais obturadores alteram a concentração do traçador utilizado no modelo de penetração de glicose, e; c) determinar se são similares os resultados de infiltração dos mesmos espécimes avaliados pelos modelos de penetração de glicose e transporte de fluidos. No primeiro estudo sessenta caninos humanos foram instrumentados e divididos em três grupos obturados por diferentes técnicas de LC e cimento AH Plus. Uma nova técnica usando uma seqüencia de espaçadores antes da colocação de um cone acessório foi comparada com duas técnicas comumente utilizadas. As raízes obturadas foram seccionadas nos níveis 3 mm e 6 mm a partir do ápice e as secções fotografadas. Usando um software de análise de imagens, as áreas do canal e de GP em cada nível foram mensuradas e a porcentagem de área obturada por guta-percha (PGP) foi calculada. Análise múltipla de variância foi utilizada para verificar as variáveis influenciando a PGP. Teste de regressão linear foi utilizado para verificar a influência da área do canal na PGP em cada nível de secção. Em ambas as secções o canal mais largo foi 2-3 vezes maior que o menos largo. Quanto maior a área do canal, menor a PGP nos níveis 6 mm (r2=0,154, P=0,02) e 3 mm (r2=0,119, P=0,007). A PGP no nível 3 mm foi menor que a 6 mm (P=0.003). A nova técnica atingiu maior PGP que as demais em ambos os níveis (P<0.05). / Different gutta-percha (GP) compaction techniques and root canal sealers may affect the final quality of the root canal filling. Recently, it was discussed a new method for evaluation of the quality of root fillings based on measuring the concentration of the glucose that penetrates through voids in the obturation. This work is divided in 3 chapters aiming to: a) determine the effects of different techniques and canal area on the quality of laterally compacted root fillings; b) verify whether different filling materials react with the tracer used in the glucose penetration model, and; c) determine whether leakage results of the same specimens measured by the glucose penetration and fluid transport are comparable. In the first study sixty extracted canines were instrumented to the same size and equally divided in three groups filled with laterally compacted GP cones and AH Plus sealer using different techniques. A new technique with use of a sequence of spreaders prior to the accessory cone placement was compared to two commonly used techniques. The filled roots were horizontally sectioned at 3 mm and 6 mm from the apex and micro-photographs of the cross-sections were taken. Using an image-analysis software, the canal and GP areas at each level were measured. The percentage of gutta-percha filled canal area (PGP) was calculated. A Multivariate analysis was used to account for the variables influencing the PGP. Linear regression test was used to verify the influence of canal area on PGP. At each level the largest canal was 2-3 times larger than the smallest. The larger the canal area, the lower the PGP at 6 mm level (r2= 0.154, P=0.02) and at 3 mm level (r2=0.119, P=0.007). The PGP at 3 mm was lower than at 6 mm (P=0.003). The new technique achieved higher PGP than other techniques (P=0.00002).

Made available in DSpace on 2014-06-11T19:32:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-23Bitstream added on 2014-06-13T20:44:30Z : No. of bitstreams: 1 santannajunior_a_dr_arafo.pdf: 417737 bytes, checksum: 315a69e964ad6046c2646a8d4a3142df (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo deste estudo foi avaliar a capacidade de preenchimento de canais laterais simulados pela guta-percha e Resilon, empregando diferentes técnicas termoplastificadoras de obturação: Condensação Vertical Aquecida (CVA), Compactação Termomecânica (CT) e Sistema Obtura II (SO). Foram utilizados 135 dentes humanos unirradiculados extraídos. Após preparo biomecânico, foram confeccionados seis canais laterais simulados em suas raízes, de acordo com a técnica proposta por Venturi et al. (2005). O diâmetro desses canais foi correspondente aos instrumentos # 08 e 10, sendo estabelecidos a 2, 5 e 8 mm do comprimento de trabalho (CT). Os espécimes foram divididos em 9 grupos (n=15), sendo: Grupo I (CVA + guta-percha Dentsply), Grupo II (CVA + Resilon), Grupo III (CVA + guta-percha Odous), Grupo IV (CT + guta-percha Dentsply), Grupo V (CT + Resilon), Grupo VI (CT + guta-percha Odous), Grupo VII (SO + guta-percha Obtura Flow 150), Grupo VIII (SO + Resilon) e Grupo IX (SO + guta-percha Odous Flow). Após a realização das obturações, os espécimes foram analisados pelos métodos radiográfico e diafanização, em função do percentual de preenchimento nos canais laterais, nos três terços. Os resultados foram submetidos ao teste de Kruskal-Wallis, com 5% de nível de significância, de acordo com avaliações específicas intra-grupos: CVA (Grupos I, II e III), CTH (Grupos IV, V e VI), SO (Grupos VII, VIII e IX) e Resilon (Grupos II, V e VIII). As avaliações CVA e CTH mostraram que o Resilon apresentou maior capacidade de preenchimento nas duas análises, em relação aos demais materiais, nos terços apical e médio (p<0,05). Quanto à avaliação SO, todos os materiais apresentaram boa capacidade de preenchimento dos canais laterais em todos os terços, com exceção do terço cervical onde o Resilon foi... / The aim of this study was to evaluate the ability of gutta-percha and Resilon to fill simulated canals using different thermoplastic obturation techniques: Warm Vertical Compaction (CVA), Thermomechanical Compaction (CTE) and Obtura II System (SO). It was used 135 extracted human teeth uniradicular. After biomechanical preparation, six simulated lateral canals were prepared in the roots, according to the technique proposed by Venturi et al. (2005). The diameter of these canals was equivalent to # 08 and 10 instruments and are set at 2, 5 and 8 mm to working length (WL). The specimens were divided into nine groups (n=15), as follow: Group I (CVA + gutta-percha Denstply), Group II (CVA + Resilon), Group III (CVA + gutta-percha Odous), Group IV (CTE + gutta-percha Dentsply), Group V (CTE + Resilon), Group VI (CTE + gutta-percha Odous), Group VII (SO + gutta-percha Obtura Flow 150), Group VIII (SO + Resilon) and Group IX (SO + gutta-percha Odous Flow). After the obturation, the samples were analyzed by radiographic and clearing methods, according to percentage of filling the lateral canals, in the three thirds. The result were submitted to the Kruskal-Wallis test at 5% significance level, according to specific intra-group evaluations: CVA (Groups I, II and III), CTH (Groups IV, V and VI), SO (Groups VII, VIII and IX) and Resilon (Groups II, V and VIII). CVA and CTH assessments showed that the Resilon has great ability to fill lateral canals in the two tests, compared to the other materials, in the apical and middle thirds (p < 0.05). As for SO evaluation, all materials showed good filling capacity of the lateral canals in all thirds, except in the cervical third where Resilon was better by radiographic analysis (extension and area) and in the cervical and middle thirds for clearing analysis (extension)... (Complete abstract click electronic access below)

Le conditionnement, opération unitaire clé du processus industriel de fabrication des produits fromagers, consiste à remplir par un jet de façon homogène des emballages de formes variées par des produits à propriétés rhéologiques complexes tout en assurant des cadences optimisées. L’objectif de cette étude est de prédire le remplissage d’un emballage, à partir de la connaissance de la rhéologie des produits et des paramètres opératoires pour le dimensionnement de nouveaux procédés de conditionnement ou l’optimisation de procédés existants.Nécessaire à la poursuite de l’étude, le comportement rhéologique des produits fromagers dans les domaines de sollicitation du procédé à 80°C a été caractérisé comme rhéofluidifiant, à seuil de contrainte, élastique en-dessous et au-dessus du seuil d’écoulement.L’hydrodynamique des jets et du remplissage lors du conditionnement a été étudiée avec trois types de produits grâce au pilote à l’échelle laboratoire du procédé, dimensionné pour reproduire les conditions opératoires industrielles. Après avoir vérifié la cohérence des résultats obtenus avec le dispositif expérimental avec ceux de la littérature pour un fluide newtonien, l’étude s’est portée sur des fluides modèles viscoplastiques, gels de Carbopol®, et sur des produits fromagers.Cinq régimes d’écoulement ont été observés et caractérisés à partir des évolutions du diamètre de jet et de la vitesse d’atteinte des bords pendant le remplissage et de la hauteur de motte finale du dépôt après le remplissage, paramètre décisif de la qualité du conditionnement. Des diagrammes de fonctionnement adimensionnels d’observation des régimes ont été déterminés à partir des forces en jeu dans le système. Ainsi, le régime d’écoulement peut être prédit par ces diagrammes à partir des propriétés rhéologiques du produit et des paramètres géométriques et opératoires du procédé. / Packaging is a key step of cheese products industrial manufacturing process. It consists in filling containers of various shapes with non-Newtonian products while ensuring optimized rates. The aim of the present work is to describe the influence of cheese rheological properties as well as process parameters onto packaging, thereby contributing towards its optimization.Necessary for the study, the rheological behavior of cheese products on the process stress range at 80°C has been identified as shear-thinning with a yield stress, with elasticity both below and above the yield stress.Jets and filling hydrodynamics during packaging have been studied with three types of products by the means of the laboratory-scale process pilot, which is able to reproduce the industrial process conditions. After checking for consistency between experimental and litterature results for Newtonian products, the study focused on viscoplastic model fluids, Carbopol® hydrogels, and on cheeses.Five flow patterns have been observed and characterized through jet diameter, spread velocity during filling and final mound height after filling, which is a key factor of the packaging quality. Flow patterns dimensionless distributions have been determined from the forces involved in the system. Thus, the flow pattern can be predicted thanks to theses distributions from product rheological properties and geometrical and process parameters.

Made available in DSpace on 2014-06-11T19:24:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-26Bitstream added on 2014-06-13T19:52:09Z : No. of bitstreams: 1 guinesi_as_me_arafo.pdf: 754134 bytes, checksum: 23c103d33c850eddf1ca5b948632482a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O propósito do presente estudo foi avaliar os cimentos endodônticos Acroseal, AH Plus, Epiphany e Polifil (cimento endodôntico experimental), no que se refere às propriedades de solubilidade e desintegração, alteração dimensional e resistência à compressão. Os testes seguiram a Norma ISO 6876-2, de 2001 e ISO 9917-1, de 2003. Nos testes de solubilidade e desintegração foram utilizados moldes de teflon (4mm de espessura, 12mm de diâmetro interno e 2mm de parede) preenchidos com cimentos endodônticos e contendo perfuração com fio de nylon para suspensão das amostras. Os espécimes foram levados à estufa até a presa dos materiais. Em seguida, as amostras hidratadas e desidratadas tiveram sua massa mensurada imediatamente após sua retirada da estufa, e após períodos de 24h, 48h, 72h, 7, 14, 30, 60 e 90 dias. A solubilidade dos cimentos endodônticos foi identificada pela alteração da massa de cada amostra, expressa como o percentual de massa perdida em comparação à massa inicial. A desintegração foi identificada visualmente, pela observação de resíduos nos recipientes e pela turbidez da água destilada. Nos testes de alteração dimensional e resistência à compressão foram utilizados moldes de teflon (12mm de espessura e 6mm de diâmetro). Os moldes foram preenchidos com cimentos endodônticos e levados à estufa até a tomada de presa, então foram removidos dos moldes e, para os testes de alteração dimensional, suas dimensões foram medidas, no sentido longitudinal, com paquímetro digital, imediatamente após sua retirada da estufa e após períodos de 24, 48 e 72 horas, 7, 14, 30, 60 e 90 dias de armazenamento. A alteração dimensional foi identificada como a percentagem de alteração volumétrica no final de cada período, em comparação ao período inicial. / Considering all the steps of the endodontic therapy, their success depend on the root canals sealing when the professional uses an endodontic sealer that gathers physical, chemical and biological properties. The aim of this study was to evaluate the endodontic sealers: Acroseal, AH Plus, Epiphany and a castor-oil based experimental sealer (Polifil) concerning the properties of solubility and disintegration, dimensional change and compressive strength. All of these tests were supposed to follow the ISO Specification 6876-2, 2001 and ISO Specification 9917-1, 2003. To perform the solubility and disintegration tests teflon rings (4 mm thickness, 12 mm of internal diameter, and 2 mm height) filled with the endodôntico sealers were used, containing perforations that allow a nylon wire passing through it, in order to get the specimens raised up. They were storaged in the oven under 37º C up to the setting time. The specimens were hydrated and dehydrated to be weighted for 24h, 48h, 72h, 7, 14, 30, 60 and 90 days. The solubility of the endodontic sealers was identified as a percentage obtained through the difference between the last measure of weight and the initial one. The disintegration were visually identified by observating the residues and the water’s whirlwind. Teflon moulds (12 mm thickness and 6mm diameter) were used in dimensional change and compressive strength tests. They were filled with the endodontic sealers and storaged in the oven under 37º C up to the setting time. Afterwards, the moulds were removed and then, for the dimensional change test, they were measured under the longitudinal position with digital pachymeter for 24h, 48h, 72h, 7, 14, 30, 60 and 90 days. The dimensional change was identified as a percentage of the volumetrical change gotten in each time, compared with the first specimen.