A comparison of the physicochemical properties of AH Plus Jet with samples taken from the beginning, middle and final portions of the automix syringe system

Aim To evaluate physicochemical properties and semi-quantitative elemental analysis of AH Plus Jet with samples from the beginning, middle and final portions of the automix syringe system. Methodology Three experimental groups based on the source of the material used (beginning, middle and final portion) were established for each of the evaluated properties. Setting time, flow and radiopacity were evaluate following ANSI/ADA n. 57 specification. Set specimens was used in the semi-quantitative elemental analysis in an energy-dispersive X ray spectroscopy and scanning-electron microscopy (EDS/SEM). Statistical analysis was performed using one-way ANOVA followed by Tukey test (P<0.05). Results Flow, setting time, solubility and EDS/SEM tests showed no significant differences among the three portions of the automix syringe (P>0.05). Radiopacity test showed significant differences in the beginning of the syringe comparing to the middle and final portions (P<0.05). EDS/SEM analysis identified the presence of C, O, Al, Ca, Zr and W. The element Al, however, was found only in the final portion of the syringe. Conclusions The results of AH Plus Jet suggested an adequate ratio of the components, without segregation between organic and inorganic components, since the results of setting time, flow, solubility and EDS/SEM analysis presented similar values regardless of the portion of the syringe from where the sealer was taken.

CAMPANELLIProgrammed Death 1 (PD-1) and PD-1 Ligand (PD-L1) Expression in Chronic Apical Periodontitis.

OBJECTIVE: This study aimed to examine programmed death protein 1 (PD-1) and programmed death lig-and 1 (PD-L1) expression on leukocytes from chronic apical periodontitis, and to determine the levels of cytokines in the apical periodontitis lesions. METHODS: Leukocytes from healthy gingival tissue (n=16) and chronic apical periodontitis (n=10) were eval-uated using flow cytometry. The PD-1 and PDL-1 expressions were evaluated using flow cytometry. The cy-tokine levels were evaluated by enzyme-linked immunosorbent assay. Data were analyzed using one-way ANOVA. The statistical significance level was set at P<0.05. RESULTS: Results showed that the apical periodontitis lesions are more infiltrated by PD-1+ and PDL1+ lym-phocytes than the control samples. In addition, the PDL-1 expression was detected on macrophages in the apical periodontitis lesions, and was significantly higher compared to leukocytes from healthy gingival tis-sue. The IFN-γ, TGF-ß, IL-10, and TNF-α levels were significantly higher in the apical periodontitis lesions com-pared to control samples. CONCLUSION: The PD-1, PD-L1, and CTLA-4 molecules are evident in apical periodontitis, and can be an impor-tant immune checkpoint in chronic periapical periodontitis.

Analysis of mandibular second molars with fused roots and shallow radicular grooves by using micro-computed tomography.

AIM: This study aimed to describe the morphological and morphometric aspects of fused mandibular second molars with radicular shallow grooves using micro-computed tomography (CT). MATERIALS AND METHODS: Eighty-eight mandibular second molars with fused roots were scanned in a micro-CT scanner at a voxel size of 19.6 µm. After reconstruction, only molars without C-shaped roots and presenting shallow radicular grooves were selected. 30 molars were chosen for further analysis. Canal cross-sections were classified according to Fan's modified classification (C1, C2, C3, and C4) and morphometric parameters at the apical region, examination of accessory foramina and tridimensional configuration were evaluated. RESULTS: Three-dimensional reconstructions indicated a higher prevalence of merging type (n = 22). According to Fan's modified classification, the C4 configuration was predominant in the 3 apical mm. Roundness median values revealed a more round-shaped canals at 3 mm (0.72) than at 2 (0.63) and 1 (0.61) mm from the apex. High values of major and minor diameters were observed in the canals of these evaluated sections. In addition, few accessory apical foramina were observed at 1 and 2 mm from the apex. The average distance between last accessory foramina and the anatomic apex was 1.17 mm. A less complex internal anatomy is found when a mandibular second molar presents fused roots with shallow radicular grooves. The merging type canal was frequently observed. Moreover, the C4 configuration was predominant at a point 3 mm from the apex and presented rounded canals, large apical diameters, and few accessory foramina. The cervical and middle thirds presented C3 and C1 canal configurations most frequently. CONCLUSION: A minor morphological complexity is found when fused mandibular second molars present shallow radicular grooves.

Variação do ângulo vertical na radiografia periapical para o diagnóstico, planejamento e tratamento endodôntico / Vertical angle variation of periapical radiograph for the diagnosis, planning and endodontic treatment

Objetivo: o objetivo do presente trabalho é discutir a importância da variação do ângulo vertical na radiografía periapical, em algumas situações clínicas especiais. Métodos: foram consultadas algumas fontes com o intuito de analisar a utilidade dessa técnica na Endodontia. Resultados: a variação do ângulo vertical na radiografía periapical pode ser empregada em diversas situações clínicas na Endodontia, tais como: a sobreposição do arco zigomático sobre os ápices dos molares superiores, para visualizar ápices muito finos, em casos de fraturas radiculares transversais, para evitar sobreposições das asas dos grampos do isolamento absoluto sobre os ápices dos dentes, durante o tratamento endodôntico. Também, poder ser útil para a detecção de obstruções cervicais do canal radicular e pinos intrarradiculares curtos, em dentes portadores de coroas metálicas, onde é difícil sua visualização. Conclusões: o uso adequado da variação na angulação vertical pode auxiliar na resolução satisfatória desses casos.

The Influence of Humidity on Intra-tubular Penetration and Bond Strength of AH Plus and MTA Fillapex: An In Vitro Study.

OBJECTIVE: The aim of this study was to evaluate the influence of humidity on the intra-tubular penetration, bond strength and failure mode associated with AH Plus (AH) and MTA Fillapex (MTAF) sealers. METHODS: For this analysis, an apparatus was created to maintain the humidity of the specimens. Sixty bovine single-rooted teeth with similar anatomy were used. The teeth were randomly divided into 4 groups (n=15): G1 - AH/moist, G2 - AH/dry, G3 - MTAF/moist and G4 - MTAF/dry. A laser scanning confocal microscope was used to analyse the penetrability of the sealers into the dentinal tubules. A push-out test was performed to examine the diameter and height of the root canal fillings. The failure mode was analysed under a stereomicroscope at 40× magnification. The data were submitted to non-parametric Kruskal-Wallis and Dunn's tests. The significance level was P<0.05. RESULTS: The MTAF sealer exhibited higher intra-tubular penetration values compared to AH Plus (P<0.05) sealer. AH Plus showed the highest bond strength values. Regarding the type of failure mode, a majority of cohesive failures was identified, irrespective of the moisture conditions, which were not statistically significant among the sealers (P<0.05). CONCLUSION: Humidity conditions did not influence the intra-tubular penetration, bond strength and failure mode of AH Plus and MTAF sealers.

Evaluation of Physicochemical Properties of a New Root Canal Sealer.

INTRODUCTION: The aim of this study was to evaluate some of the physicochemical properties of a new root canal sealer. METHODS: The sealers tested were Sealer Plus compared with AH Plus. For the radiopacity, flow, solubility, and fabrication of test specimens relative to setting times, the American National Standards Institute/American Dental Association No. 57 (2000) and International Organization for Standardization 6876 (2012) specifications were followed. To measure the initial and final setting times, the ASTM C266/2008 standard was used. pH was evaluated in the time intervals of 3, 24, 72, and 168 hours. Statistical tests were applied to the results obtained at a level of significance of 5%. RESULTS: The results demonstrated that the Sealer Plus sealer showed a lower radiopacity value than AH Plus sealer (P < .05); however, this was higher than the minimum value recommended by the specifications (ie, 3 mm Al). Relative to flow, the value for Sealer Plus was 19.19 mm and for AH Plus, 19.81 mm (P > .05). Sealer Plus presented initial and final setting times of 138 minutes and 210 minutes, respectively, whereas the values for AH Plus were 437 minutes and 849 minutes, respectively (P < .05). Relative to solubility, Sealer Plus presented 0.21% and AH Plus, 0.27% (P > .05). None of the sealers showed a significant increase in pH (P > .05). CONCLUSIONS: Sealer Plus sealer presented physicochemical properties in accordance with American National Standards Institute/American Dental Association (2000) No. 57 and International Organization for Standardization 6876 (2012) specifications.

Smear layer na endodontia, preservar ou remover? / Smear layer in endodontics, preserve or remove?

Introdução: todo canal radicular instrumentado, seja por métodos manuais ou rotatórios, apresentará a formação de uma lama de detritos sobre a parede dentinária, sendo esta composta tanto por matéria orgânica quanto inorgânica, denominada de smear layer. Em relação a sua remoção ou manutenção das paredes do canal, diversos autores apresentaram opiniões e resultados divergentes, gerando dúvidas aos clínicos em relação à conduta mais adequada a ser empregada no tratamento endodôntico. Objetivo: este trabalho, por meio de uma revisão de literatura, visa fornecer uma resposta clara, capaz de melhorar o prognóstico do tratamento. Metodologia: para isso, foram utilizados 25 trabalhos desde o ano de 1975 a 2014, coletados por meio das bases de dados PubMed e Web of Science, com as palavras chaves: "smear layer", "smear layer removal", "smear layer permeability", "smear layer bacteria" e "smear layer sealing". Conclusão: baseado na metodologia proposta pode-se concluir que a remoção da smear layer é a melhor conduta a ser tomada durante o tratamento endodôntico, pois proporciona uma ação antimicrobiana mais eficiente das substâncias irrigadoras e medicações intracanais, além de permitir um melhor selamento entre dentina e material obturador, reduzindo as chances de uma infiltração.

Introduction: the root canal instrumentation, either by manual or mechanicals methods, will result in a formation of debris layer on dentin surface composted by organic and inorganic tissues, denominated smear layer. Due to the several divergent opinion about its removal or maintenance into the root canal, the clinicians may have a doubt for the most appropriate conduct to be performed in endodontics treatments. Objective: this article aimed collect the mains results obtained by different authors to provide a clear answer capable of improving the treatment prognosis. Methods: for this, were used 25 articles since 1975 to 2014 collected by date base PubMed and Web of Science with the keywords "smear layer", "smear layer removal", "smear layer permeability", "smear layer bacteria" and "smear layer sealing". Conclusion: based in the informations obtained in this review, its was concluded that the smear layer removal can, not only, improve the antimicrobial action of the irrigants agents and intracanal medicaments, but also provide a most efficient sealing of the fillingmaterial to dentine wall, reducing the chances to occur a leak in its interface.

Influência do hidróxido de cálcio na adaptação e na penetração às paredes do canal de dentes obturados com um cimento resinoso à base de metacrilato / The influence of calcium hydroxide on adaptation and root canal penetration in teeth filled with methacrylate-based resin sealer

Introdução: o objetivo deste trabalho foi avaliar, por meio da microscopia confocal de varredura a laser (MCVL), o efeito da medicação intracanal com pasta de hidróxido de cálcio sobre a penetração e a porcentagem de adaptação — nos terços cervical, médio e apical — de canais obturados com o sistema obturador à base de metacrilato (Sistema Epiphany). Métodos: trinta incisivos inferiores humanos foram instrumentados até a lima 40.04 do sistema ProFile e a solução irrigadora usada foi o hipoclorito de sódio. Os dentes foram aleatoriamente divididos em três grupos (n = 10): Grupo I = sem hidróxido de cálcio (Ca(OH)2) (grupo controle); Grupo II = com Ca(OH)2 por 14 dias e remoção com solução salina + lima K #40; e Grupo III = similar ao Grupo II, mas utilizando o EDTA a 17% para remoção da medicação. O cimento Epiphany foi corado com rodamina B, e todos os canais foram obturados com o sistema Epiphany. Três secções de cada dente foram avaliadas sob magnificações de cinco e de quarenta vezes. Resultados: os testes estatísticos de ANOVA e Tukey indicaram significância estatística na redução dos valores de penetração do cimento no terço apical, comparado aos outros terços (p < 0,05). A maior profundidade de penetração foi observada nos terços coronal e médio do Grupo II. Os Grupos II (93%) e III (86%) tiveram as maiores porcentagens de adaptação, comparados ao Grupo I (78%) (p < 0,05). Conclusões: o Ca(OH)2 favoreceu a profundidade de penetração do cimento e a porcentagem de adaptação na interface dentina/cimento em dentes obturados com o cimento à base de metacrilato.

A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy

Objectives To compare three methods of intratubular contamination that simulate endodontic infections using confocal laser scanning microscopy (CLSM). Material and Methods Two pre-existing models of dentinal contamination were used to induce intratubular infection (groups A and B). These methods were modified in an attempt to improve the model (group C). Among the modifications it may be included: specimen contamination for five days, ultrasonic bath with BHI broth after specimen sterilization, use of E. faecalisduring the exponential growth phase, greater concentration of inoculum, and two cycles of centrifugation on alternate days with changes of culture media. All specimens were longitudinally sectioned and stained with of LIVE/DEAD® for 20 min. Specimens were assessed using CLSM, which provided images of the depth of viable bacterial proliferation inside the dentinal tubules. Additionally, three examiners used scores to classify the CLSM images according to the following parameters: homogeneity, density, and depth of the bacterial contamination inside the dentinal tubules. Kruskal-Wallis and Dunn’s tests were used to evaluate the live and dead cells rates, and the scores obtained. Results The contamination scores revealed higher contamination levels in group C when compared with groups A and B (p<0.05). No differences were observed between group A and B (p>0.05). The volume of live cells in group C was higher than in groups A and B (p<0.05). Conclusion The new protocol for intratubular infection resulted in high and uniform patterns of bacterial contamination and higher cell viability in all specimens when compared with the current methods.

A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy.

OBJECTIVES: To compare three methods of intratubular contamination that simulate endodontic infections using confocal laser scanning microscopy (CLSM). MATERIAL AND METHODS: Two pre-existing models of dentinal contamination were used to induce intratubular infection (groups A and B). These methods were modified in an attempt to improve the model (group C). Among the modifications it may be included: specimen contamination for five days, ultrasonic bath with BHI broth after specimen sterilization, use of E. faecalisduring the exponential growth phase, greater concentration of inoculum, and two cycles of centrifugation on alternate days with changes of culture media. All specimens were longitudinally sectioned and stained with of LIVE/DEAD for 20 min. Specimens were assessed using CLSM, which provided images of the depth of viable bacterial proliferation inside the dentinal tubules. Additionally, three examiners used scores to classify the CLSM images according to the following parameters: homogeneity, density, and depth of the bacterial contamination inside the dentinal tubules. Kruskal-Wallis and Dunn's tests were used to evaluate the live and dead cells rates, and the scores obtained. RESULTS: The contamination scores revealed higher contamination levels in group C when compared with groups A and B (p<0.05). No differences were observed between group A and B (p>0.05). The volume of live cells in group C was higher than in groups A and B (p<0.05). CONCLUSION: The new protocol for intratubular infection resulted in high and uniform patterns of bacterial contamination and higher cell viability in all specimens when compared with the current methods.

Efeitos de diferentes aditivos sobre as propriedades antimicrobianas, físicas e químicas do agregado trióxido mineral (MTA) / Effects of various additives on antimicrobial, physical and chemical properties of mineral trioxide aggregate (MTA)

Objetivo: verificar a ação antimicrobiana, solubilidade, tempo de presa, escoamento, pH, liberação de cálcio e característica da superfície do MTA associado as substancias hipoclorito de sodio gel a 1%, clorexidina gel a 2%, água destilada associada a 10% de propilenoglicol (CCPG), K-Y gel, solução salina e, por fim, água destilada. Métodos: para o teste antimicrobiano, utilizou-se o Streptococcus mutans, Lactobacillus casei, Enterococcus faecalis e Candida albicans, por meio do método de contato direto. Para avaliação do tempo de presa e escoamento, foram utilizadas as especificações ASTM 266/08 e ADA 57/2007. Para o pH e liberação de cálcio, os materiais foram inseridos em cavidades retrogradas de dentes de resina acrílica e imersos em água ultrapura, para avaliação em diferentes períodos, utilizando um pHmetro e um espectrofotômetro de absorção atômica. Para a analise das características de superfície, os dentes de acrílico foram analisados com microscopia eletrônica de varredura (MEV). Resultados: os resultados dos testes antimicrobianos mostraram que os diferentes aditivos associados ao MTA apresentaram maior propriedade inibitória do que bactericida, sendo que a clorexidina apresentou os melhores resultados. As amostras que utilizaram o K-Y gel como veiculo apresentaram maiores índices de solubilidade. Houve diferença estatística entre os grupos (p > 0,05) quanto ao escoamento. O grupo que utilizou o CCPG apresentou o menor tempo de presa. O grupo K-Y apresentou os menores pH e liberação de cálcio no período de três horas. Nos outros períodos, houve maior uniformidade entre os grupos. Com relação as características da superfície, o grupo CCPG apresentou a maior porosidade (p < 0,05). Conclusão: o único veiculo avaliado que proporcionou alguma melhora no efeito antimicrobiano foi a clorexidina gel a 2%. Ja o K-Y gel interferiu nas propriedades físico-químicas do MTA, e a adição de CCPG proporcionou a maior porosidade.

Micro-computed Tomographic Analysis of Mandibular Second Molars with C-shaped Root Canals.

INTRODUCTION: The goal of the present study was to evaluate the morphometric aspects of the internal anatomy of the root canal system of mandibular second molars with C-shaped canals. METHODS: Fifty-two extracted second mandibular molars with C-shaped canals, fused roots, and radicular grooves were selected from a Brazilian population. The samples were scanned with a micro-computed tomographic scanner at a voxel size of 19.6 µm. The root canal cross sections were recorded as C1, C2, C3, and C4 root canal configurations according to the modified Melton classification. Morphometric parameters, including the major and minor diameters of the root canals, the aspect ratio, the roundness, and the tridimensional configuration (merging, symmetric, and asymmetric), were evaluated. RESULTS: The 3-dimensional reconstruction images of the teeth indicated an even distribution within the sample. The analysis of the prevalence of the different cross-sectional configurations of the C-shaped molars revealed that these were predominantly of the C4 and C3 configurations (1 mm from the apex) and the C1 and C2 configurations in the cervical third. According to the morphometric parameters, the C1 and the distal aspect of the C2 configurations exhibited the lowest roundness values and higher values for the area, major diameter, and aspect ratio in the apical third. CONCLUSIONS: Mandibular molars with C-shaped root canals exhibited similar distributions of symmetric, asymmetric, and merging type canals. The C1 configuration and the distal aspect of the C2 configuration exhibited the highest area values, low roundness values, and large apical diameters.

Rat subcutaneous tissue response to calcium silicate containing different arsenic concentrations

Objective: To evaluate the response of rat subcutaneous tissue in implanted polyethylene tubes that were filled with GMTA Angelus and Portland cements containing different arsenic concentrations. Material and Methods: Atomic absorption spectrophotometry was utilized to obtain the values of the arsenic concentration in the materials. Thirty-six rats were divided into 3 groups of 12 animals for each experimental period. Each animal received two implants of polyethylene tubes filled with different test cements and the lateral of the tubes was used as a control group. After 15, 30 and 60 days of implantation, the animals were killed and the specimens were prepared for descriptive and morphometric analysis considering: inflammatory cells, collagen fibers, fibroblasts, blood vessels and other components. The results were analyzed utilizing the Kuskal-Wallis test and the Dunn's Multiple test for comparison (p<0.05). Results: The materials showed, according to atomic absorption spectrophotometry, the following doses of arsenic: GMTA Angelus: 5.01 mg/kg, WPC Irajazinho: 0.69 mg/kg, GPC Minetti: 18.46 mg/kg and GPC Votoran: 10.76 mg/kg. In a 60-day periods, all specimens displayed a neoformation of connective tissue with a structure of fibrocellular aspect (capsule). Control groups and MTA Angelus produced the lower amount of inflammatory reaction and GPC Minetti, the highest reaction. Conclusions: There was no direct relationship between the concentration of arsenic present in the composition of the materials and the intensity of the inflammatory reactions. Higher values, as 18.46 mg/kg of arsenic in the cement, produce characteristics of severe inflammation reaction at the 60-day period. The best results were found in MTA angelus. .

Rat subcutaneous tissue response to calcium silicate containing different arsenic concentrations.

OBJECTIVE: To evaluate the response of rat subcutaneous tissue in implanted polyethylene tubes that were filled with GMTA Angelus and Portland cements containing different arsenic concentrations. MATERIAL AND METHODS: Atomic absorption spectrophotometry was utilized to obtain the values of the arsenic concentration in the materials. Thirty-six rats were divided into 3 groups of 12 animals for each experimental period. Each animal received two implants of polyethylene tubes filled with different test cements and the lateral of the tubes was used as a control group. After 15, 30 and 60 days of implantation, the animals were killed and the specimens were prepared for descriptive and morphometric analysis considering: inflammatory cells, collagen fibers, fibroblasts, blood vessels and other components. The results were analyzed utilizing the Kuskal-Wallis test and the Dunn's Multiple test for comparison (p<0.05). RESULTS: The materials showed, according to atomic absorption spectrophotometry, the following doses of arsenic: GMTA Angelus: 5.01 mg/kg, WPC Irajazinho: 0.69 mg/kg, GPC Minetti: 18.46 mg/kg and GPC Votoran: 10.76 mg/kg. In a 60-day periods, all specimens displayed a neoformation of connective tissue with a structure of fibrocellular aspect (capsule). Control groups and MTA Angelus produced the lower amount of inflammatory reaction and GPC Minetti, the highest reaction. CONCLUSIONS: There was no direct relationship between the concentration of arsenic present in the composition of the materials and the intensity of the inflammatory reactions. Higher values, as 18.46 mg/kg of arsenic in the cement, produce characteristics of severe inflammation reaction at the 60-day period. The best results were found in MTA angelus.

Influência do perborato de sódio na desadaptação marginal de tampões cervicais confeccionados com diferentes materiais / Influence of sodium perborate on marginal misfit in cervical barrier made by different materials

Frente aos efeitos deletérios da reabsorção cervical externa, é de grande importância a confecção do tampão cervical quando do clareamento de dentes despolpados. Objetivo: este estudo avaliou a influência do perborato de sódio (PS) e o número de aplicações na desadaptação marginal do tampão cervical. Metodologia: Vinte e quatro pré-molares inferiores foram divididos em três grupos (n=8), de acordo com o material utilizado na confecção do tampão: Cimento de Ionômero de Vidro (CIV), Bioplic (BP) e Agregado de Trióxido Mineral branco (MTA B). Após a aplicação dos materiais, os espécimes foram aplainados e registrados por uma câmera fotográfica acoplada ao Esteromicroscópio. O PS diluído em soro fisiológico foi acomodado sobre os tampões e em seguida selados por 15 dias. Em seguida, o PS foi removido e novas imagens realizadas no Estereomicroscópio. Este ciclo foi repetido, determinando três períodos de avaliação. A desadaptação marginal foi calculada por meio do Software Image J, e os dados submetidos ao teste estatístico de Kruskal-wallis com post-hoc de Dunn para comparação intergrupos (α menor ou igual a 0,05), e teste de Friedman para comparação intragrupos (α menor ou igual a 0,05). Resultados: Verificou-se um aumento significativo na desadaptação marginal do BP e CIV entre os períodos controle e 2ª sessão. Na comparação intergrupos, o MTA B apresentou maior desadaptação quando comparado ao BP em todos os períodos. Conclusão: o PS foi capaz de aumentar a desadaptação marginal de dois materiais após 30 dias, e o MTA B seria o material menos indicado para confecção do tampão cervical...

Due to the deleterious effects of the external cervical resorption, it is extremely important the use of an appropriate cervical barrier in non-vital bleaching. Objective: this study evaluated the influence of sodium perborate (SP) and the number of its application on cervical barrier marginal misfit. Methods: twenty- four human premolars were divided into 3 groups (n=8) according to the material used in manufacture of barrier: Glass Ionomer cement (GIC), Bioplic (BP) and white Mineral Trioxide aggregate (W MTA). After the application of the materials, specimens were planed and registered with a camera mounted in a stereomicroscope. SP diluted in saline was accommodated on the barrier and then sealed for 15 days. Afterwards SP was removed and images were again obtained with stereomicroscope. This cycle was repeated once more, determine three periods of evaluation. Marginal misfit was obtained through Image J software, and the data was subjected to two-way analysis of variance, followed by Tukey post-hoc test (α or less 0,05). Results: there was a significant increase in the marginal misfit of BP and CIV between periods control and 2nd session. In the intergroup comparison, the MTA B showed larger marginal misfit when compared to BP in all periods. Conclusion: the PS was able to increase marginal misfit of 2 materials after 30 days, and the MTA B would be less suitable for making the cervical barrier...

Seladores coronários temporários usados em endodontia: revisão de literatura / Temporary Coronary Sealers used in Endodontics: Literature Review

Entende-se que o selamento coronário é tão importante para o sucesso da terapia endodôntica quanto o próprio tratamento em si, podendo ser considerado parte integral deste. Objetivo: realizar uma revisão de literatura sobre os principais seladores coronários temporários e suas propriedades, para elucidar aos endodontistas e clínicos gerais, qual as melhores opções. Resultados e Discussão: a melhor capacidade de vedamento foi atribuída a materiais fotoativados, cimento de ionômero de vidro e coltosol. Porém, a variação de metodologias encontrados na literatura é grande, tornando difícil suas comparações. Conclusões: existe a necessidade de padronização destes testes, e verificação de sua legitimidade para que possamos ter conclusões concretas sobre o assunto em questão...

It is known that the coronal sealing ability is so important to the endodontic therapy`s success, as the treatment itself, could being considered an integral part of it. Objective: a literature review of the main temporary filling materials and their properties, for the avoidance of the incorrect use of these, by endodontics and general practitioners. Results and Discussion: photoactive material, Ionomer Cement Glass and Coltosol were found to exhibit the best coronal seal. However, variation of regimens used in literature was large, making comparison of reports difficult. Conclusion: it is necessary the standardization of these tests and checking of its legitimacy, so we will have concrete conclusions on the subject in question...

Microscopic analysis of the quality of obturation and physical properties of MTA Fillapex.

This study analyzed the quality of obturation and physical properties of MTA Fillapex and AH Plus sealer. A sample of 30 human maxillary central incisors were instrumented with Protaper until a F5 (50/05) file. Both sealers were mixed with Rhodamine-B dye to allow visualization on a confocal laser-scanning microscope (CLSM). Next, the canals were filled using the single cone technique. After setting, all samples were sectioned at 2, 4, and 6 mm from the apex. CLSM was used to analyze the gaps and sealer penetration into the dentinal tubules. All samples were scanned 10 µm below the dentin surface and images were recorded at 100× magnification using the fluorescent mode. Additionally, the solubility, flowability and setting time of the sealers were evaluated. All the measured quantities of the examined materials were evaluated for significant differences by means of statistical analysis. The CLSM analysis of the MTA Fillapex showed the highest percentage of gaps at all sections (P = 0.0001). Physical tests revealed adequate properties for both sealers except for a higher solubility of the MTA Fillapex (P = 0.0001). The MTA Fillapex presented flowability and intratubular penetration similar to the AH Plus. Nevertheless, the MTA Fillapex sealer presented a higher solubility and considerable quantity of gaps between the sealer/dentin interface in relation to the AH Plus sealer. Clinicians must take into consideration, the quality of endodontic sealers as it is essential in the outcome of the root canal filling.

Apical adaptation, sealing ability and push-out bond strength of five root-end filling materials.

This study compared the fluid filtration, adaptation to the root canal walls, and the push-out bond strength of two resin-based sealers and three calcium silicate-based retrograde filling materials. Fifty maxillary canines were shaped using manual instruments and the apical portion was sectioned. Retrograde cavities of 3-mm depth were prepared. The specimens were divided into five groups (n = 10): Sealer 26 (S26); MBPc (experimental); MTA; Portland cement with 20% zirconium oxide (PC/ZO), and Portland cement with 20% calcium tungstate (PC/CT). The fluid filtration was measured at 7 and 15 days. To evaluate the interfacial adaptation, sections of the teeth, 1 and 2 mm from the apex, were prepared and the percentage of gaps was calculated. The push-out bond strength at 2 mm from the apex was evaluated. Statistical analysis was performed using the ANOVA/Tukey's test (p < 0.05). At 7 and 15 days (p = 0.0048, p = 0.006), the PC/CT group showed higher fluid filtration values when compared to other groups. At 1 mm from the apex, no statistical differences in the adaptation were found among the cements (p = 0.44). At 2 mm from the apex, the PC/ZO group presented statistically lower percentage of gaps than S26, MBPc, and MTA (p = 0.0007). The MBPc group showed higher push-out bond strength than other cements evaluated (p = 0.0008). The fluid filtration and interfacial adaptation of the calcium silicate-based cements were similar to those of the resin-based cements. The resinous cement MBPc showed superior push-out bond strength.

Biocompatibility and setting time of CPM-MTA and white Portland cement clinker with or without calcium sulfate.

OBJECTIVE: To evaluate the biocompatibility and the setting time of Portland cement clinker with or without 2% or 5% calcium sulfate and MTA-CPM. MATERIAL AND METHODS: Twenty-four mice (Rattus norvegicus) received subcutaneously polyethylene tubes filled with Portland cement clinker with or without 2% or 5% calcium sulfate and MTA. After 15, 30 and 60 days of implantation, the animals were killed and specimens were prepared for microscopic analysis. For evaluation of the setting time, each material was analyzed using Gilmore needles weighing 113.5 g and 456.5 g, according to the ASTM specification Number C266-08 guideline. Data were analyzed by ANOVA and Tukey's test for setting time and Kruskal-Wallis and Dunn test for biocompatibility at 5% significance level. RESULTS: Histologic observation showed no statistically significant difference of biocompatibility (p>0.05) among the materials in the subcutaneous tissues. For the setting time, clinker without calcium sulfate showed the shortest initial and final setting times (6.18 s/21.48 s), followed by clinker with 2% calcium sulfate (9.22 s/25.33 s), clinker with 5% calcium sulfate (10.06 s/42.46 s) and MTA (15.01 s/42.46 s). CONCLUSIONS: All the tested materials showed biocompatibility and the calcium sulfate absence shortened the initial and final setting times of the white Portland cement clinker.

Antimicrobial activity of calcium hydroxide and chlorhexidine on intratubular Candida albicans.

This study investigated the efficacy of calcium hydroxide and chlorhexidine gel for the elimination of intratubular Candida albicans (C. albicans). Human single-rooted teeth contaminated with C. albicans were treated with calcium hydroxide, 2% chlorhexidine gel, calcium hydroxide plus 2% chlorhexidine gel, or saline (0.9% sodium chloride) as a positive control. The samples obtained at depths of 0-100 and 100-200 µm from the root canal system were analyzed for C. albicans load by counting the number of colony forming units and for the percentage of viable C. albicans using fluorescence microscopy. First, the antimicrobial activity of calcium hydroxide and the 2% chlorhexidine gel was evaluated by counting the number of colony forming units. After 14 days of intracanal medication, there was a significant decrease in the number of C. albicans colony forming units at a depth of 0-100 µm with chlorhexidine treatment either with or without calcium hydroxide compared with the calcium hydroxide only treatment. However, there were no differences in the number of colony forming units at the 100-200 µm depth for any of the medications investigated. C. albicans viability was also evaluated by vital staining techniques and fluorescence microscopy analysis. Antifungal activity against C. albicans significantly increased at both depths in the chlorhexidine groups with and without calcium hydroxide compared with the groups treated with calcium hydroxide only. Treatments with only chlorhexidine or chlorhexidine in combination with calcium hydroxide were effective for elimination of C. albicans.