Cytotoxicity, inflammation, biomineralization, and immunoexpression of IL-1β and TNF-α promoted by a new bioceramic cement

Aim: To evaluate the cytotoxicity, biocompatibility and mineralization capacity of BIO-C PULPO, and MTA. Methodology: L929 fibroblasts were cultured and MTT assay was used to determine the material cytotoxicity on 6, 24, and 48 h. A total of 30 male rats (Wistar) aged between 4 and 6 months, weighing between 250 and 300 g were used. Polyethylene tubes containing BIO-C PULPO, MTA, and empty tubes were implanted into dorsal connective tissue. After the experimental periods (7, 15, 30, 60, and 90 days) the tubes were histologically analyzed using hematoxylin-eosin (H&E), immunolabeling of IL-1β and TNF-α, and von Kossa staining, or without staining for polarized light analysis. The average number of inflammatory cells was quantified; the mineralization assessment was determined by the area marked in μm2 and semiquantitative immunolabeling analyses of IL-1β and TNF-α were performed. Then, data underwent statistical analysis with a 5% significance level. Results: It was observed that BIO-C PULPO and MTA presented cytocompatibility at 6, 24, and 48 similar or higher than control for all evaluated period. On periods 7 and 15 days, BIO-C PULPO was the material with the highest number of inflammatory cells (p<0.05). On periods 30, 60, and 90 days, BIO-C PULPO and MTA presented similar inflammatory reactions (p>0.05). No statistical differences were found between Control, BIO-C PULPO, and MTA for immunolabeling of IL-1β and TNF-α in the different periods of analysis (p<0.05). Positive von Kossa staining and birefringent structures under polarized light were observed in all analyzed periods in contact with both materials, but larger mineralization area was found with BIO-C PULPO on day 90 (p<0.05). Conclusion: BIO-C PULPO was biocompatible and induced mineralization similar to MTA

Influence of the Vehicle on the Tissue Reaction and Biomineralization of Fast Endodontic Cement

Objective: To investigate the tissue response and the biomineralization ability of CER prepared with epoxy resin or water compared to Mineral Trioxide Aggregate (MTA). Material and Methods: Polyethylene tubes containing materials or empty tubes for control were inserted into the subcutaneous tissues of 30 rats. After 7, 15, 30, 60, and 90 days, the rats were killed and the tubes were removed for analysis using hematoxylin-eosin staining, von Kossa staining, and under polarized light. Inflammation was graded through a score system; the thickness of the fibrous capsule was classified as thin or thick; the biomineralization ability was recorded as present or absent. The results were statistically analyzed using the Kruskal-Wallis test (p<0.05). Results: Histologic analysis performed after 7 and 15 days for CER prepared with epoxy resin or water and for MTA showed moderate inflammation and a thick fibrous capsule (p>0.05). After 30, 60, and 90 days, mild inflammation, and a thin fibrous capsule were observed in all groups (p>0.05). Conclusion: All materials had structures positive for von Kossa and birefringent to polarized light. CER epoxy resin showed biocompatibility and biomineralization similar to CER water and MTA

Antimicrobial action of calcium hydroxide-based endodontic sealers after setting, against E. faecalis biofilm

Abstract Enterococcus faecalis are gram positive bacteria that can mostly resist endodontic therapy, inducing persistent infection in the root canal system. Endodontic sealers with antimicrobial activity may help eliminate residual microorganisms that survive endodontic treatment. The present study aimed at comparing the antimicrobial activity of Acroseal, Sealapex and AH Plus endodontic sealers in an in vitro biofilm model. Bovine dentin specimens (144) were prepared, and twelve blocks for each sealer and each experimental time point (2, 7 and 14 days) were placed and left in contact with plates containing inoculum of E. faecalis (ATCC 51299), to induce biofilm formation. After 14 days, the samples were transferred to another plate with test sealers and kept at 37°C and 5% CO2 for 2, 7 and 14 days. The specimens without sealers were used as a control for each period. The samples were agitated in a sonicator after each experiment. The suspensions were agitated in a vortex mixer, serially diluted in saline, and triple plated onto m-Enterococcus agar. Colonyforming units were counted, and the data were statistically analyzed using ANOVA, Shapiro-Wilk and Kruskal-Wallis one-way tests (p < 0.05) to determine antimicrobial potential. Sealapex showed significant differences at all the experimental time points, in comparison with all the other groups. AH Plus and Acroseal showed antimicrobial activity only on the 14th experimental day. Neither of the sealers tested were able to completely eliminate the biofilm. Sealapex showed the highest antimicrobial activity in all the experimental periods. The antimicrobial activity of all the sealers analyzed increased over time

Influence of diabetes mellitus on tissue response to MTA and its ability to stimulate mineralization

AimTo evaluate the influence of diabetes mellitus on the tissue response to mineral trioxide aggregate (MTA) and its ability to stimulate mineralization.MethodsTwenty-four male Wistar rats were divided into a non-diabetic control group and another with Alloxan-induced diabetes. Two polyethylene tubes, one kept empty as a control and the other containing Angelus MTA((R)), were implanted into the dorsal connective tissue of all rats for 30days. Animals in each group received injections of calcein, alizarin, and oxytetracycline on day 7, 14, and 21, respectively. Animals were killed after 30days; specimens were prepared by staining with hematoxylin and eosin (HE) and von Kossa technique as well as for examination of unstained sections with polarized light and fluorescence microscopy.ResultsThe inflammatory reaction to the implanted tubes was equally mild in both groups. Structures staining with von Kossa were seen in response to Angelus MTA((R)), as were birefringent structures visualized on polarized light analysis; these had no relation to diabetic condition (P&lt;0.05). Fluorescence intensity was not changed in diabetic rats either (P&lt;0.05).ConclusionDiabetes mellitus did not influence the tissue response to Angelus MTA((R)) or the mineralization stimulated by it.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Terapia fotodinâmica na Endodontia: emprego de uma estratégia coadjuvante frente à infecção endodôntica

O tratamento endodôntico é de fundamental importância para abolir a infecção nos dentes com necrose pulpar. O sucesso desse tratamento depende: da eliminação eficiente da infecção no sistema de canais radiculares (SCR) e do correto selamento pela obturação dos canais radiculares. Devido à complexidade anatômica do SCR, certas áreas podem ser inacessíveis ao preparo biomecânico (PBM), portanto, o emprego de uma medicação intracanal potencializa a redução dos microrganismos (MO) e seus produtos tóxicos no SCR. Mesmo com o avanço técnico e científico da Endodontia, há MO que ainda sobrevivem ao PBM, sendo os principais responsáveis pela manutenção infecção endodôntica. Assim, novos tratamentos devem ser pesquisados. Com o advento dos aparelhos de laser e LED, surgiram alternativas de tratamentos na área da saúde, como a terapia fotodinâmica (TFD), que é um conjunto de procedimentos físicos, químicos e biológicos, que ocorrem após a administração de um agente fotossensibilizador (FS) ativado por meio de uma luz visível de comprimento de onda específico (laser ou LED) para destruir a célula-alvo, ou auxiliar no combate das infecções. Na Endodontia, foram demonstrados em estudos in vitro e in vivo que o emprego da TFD atua como um coadjuvante e potencializa a desinfecção do SCR, além de ser de fácil aplicação e não promover resistência microbiana. O objetivo da presente revisão é apresentar o estado atual da terapia fotodinâmica em Endodontia

Avaliação das nanopartículas de prata como solução irrigadora

Introdução: a irrigação é um procedimento importante durante o tratamento do canal radicular, auxiliando na limpeza de áreas do sistema de canais radiculares que não são alcançadas diretamente por instrumentos. Objetivo: o objetivo desse estudo foi avaliar a biocompatibilidade e a capacidade de desinfecção de nanopartículas de prata em dispersão, em comparação ao hipoclorito de sódio a 2,5%. Métodos: trinta ratos receberam, individualmente, quatro tubos de dentina infectados e não infectados, irrigados com dispersão de nanopartículas de prata 47ppm e 23ppm, hipoclorito de sódio a 2,5% e solução salina. Dezesseis ratos receberam um tubo de dentina infectada e um tubo de dentina não infectada como grupo controle. Após 7 e 30 dias, os animais foram sacrificados, os tubos e o tecido circundante foram removidos e preparados para análise em microscopia de luz. Avaliações qualitativas e quantitativas das reações foram realizadas. Resultados: todas as soluções em tubos não infectados causaram reações leves em 30 dias. Todas as soluções em tubos infectados causaram reações graves em 7 dias e leves em 30 dias. As respostas foram semelhantes às do grupo controle não infectado, mas melhores do que o grupo controle infectado. Conclusões: foi possível concluir que nanopartículas de prata em dispersão são biocompatíveis e podem atuar na desinfecção de tubos contaminados, especialmente em concentrações de 23ppm