Long-term cytotoxic effects of contemporary root canal sealers

Objectives: The aim of the present study was to investigate the effects of root canal sealers on the cytotoxicity of 3T3 fibroblasts during a period of 5 weeks. Material and Methods: Fibroblasts (3T3, 1x10(5) cells per well) were incubated with elutes of fresh specimens from eight root canal sealers (AH Plus, Epiphany, Endomethasone N, EndoREZ, MTA Fillapex, Pulp Canal Sealer EWT, RoekoSeal and Sealapex) and with elutes of the same specimens for 5 succeeding weeks after immersing in simulated body fluid. The cytotoxicity of all root canal sealers was determined using the MU assay. Data were analyzed using ANOVA and Tukey's test. Results: RoekoSeal was the only sealer that did not show any cytotoxic effects (p<0.05). All the other tested sealers exhibited severe toxicity initially (week 0). MTA Fillapex remained moderately cytotoxic after the end of experimental period. Toxicity of the other tested sealers decreased gradually over time. The evaluated root canal sealers presented varying degrees of cytotoxicity, mainly in fresh mode. Conclusions: RoekoSeal had no cytotoxic effect both freshly mixed and in the other tested time points. MTA Fillapex was associated with significantly less cell viability when compared to the other tested root canal sealers.211434

Effects of Reducing Agents on Birefringence Dentin Collagen after Use of Different Endodontic Auxiliary Chemical Substances

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Introduction: The aim of this study was to evaluate the effect of 10% ascorbic acid or 10% sodium ascorbate on organic matrix collagen of bovine dentin root canal walls after irrigation with 5.25% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA), or 0.9% sodium chloride. Methods: Eighty bovine incisors were randomly divided into 8 groups (n = 10): group 1, 0.9% sodium chloride (control); group 2, 5.25% NaOCl + 17% EDTA (NaOCl + EDTA); group 3, 5.25% NaOCl + 17% EDTA + 10% ascorbic acid (NaOCl + EDTA + AA); group 4, 5.25% NaOCl + 17% EDTA + 10% sodium ascorbate (NaOCl + EDTA + SA); group 5, 5.25% NaOCl (NaOCl); group 6, 17% EDTA; group 7, 10% ascorbic acid (AA); and group 8, 10% sodium ascorbate (SA). Teeth were chemomechanically prepared, submitted to histologic processing, and stained with Sirius Red dye to be analyzed under polarized light microscopy. Absorbance assay was also performed to confirm the loss of collagen. Results: NaOCl + EDTA and NaOCl groups presented a significantly different birefringence pattern compared with the control group (P < .05). The measurement of the optical retardations of NaOCl + EDTA + SA indicated that this group was not statistically different from the control group. Although the measurement of the optical retardations of NaOCl + EDTA + AA was statistically different from the control group, the results were significantly higher than for NaOCl + EDTA. The birefringence of EDTA, AA, and SA groups was not statistically different from that of control group. The absorbance assay of NaOCl + EDTA and NaOCl groups confirmed the loss of collagen (P<.05). Conclusions: It is possible to conclude that 5.25% NaOCl, whether associated or not with 17% EDTA, causes birefringence alterations and loss of dentin collagen. These alterations reduced the ability of Sirius Red to bind with collagen fiber molecules. The reductions in the optical retardation values could be reversed by the application of either 10% ascorbic acid or 10% sodium ascorbate after 5.25% sodium hypochlorite and 17% EDTA irrigation. (J Endod 2011;37:1406-1411)371014061411Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq [141281/2007-3

A multiparametric assay to compare the cytotoxicity of soy milk with different storage media

Background/Aim: The aim of this study was to evaluate the cytotoxicity of soy milk compared with several other storage media [coconut water, Hank's Balanced Salt Solution (HBSS) and whole milk], assessed through a multiparametric analysis employing 3T3 cells. Materials and methods: Plates containing confluent 3T3 fibroblasts were exposed to the various media for 24 h, at 37 degrees C with 5% CO2, and cell viability was evaluated by a multiparametric assay assessing sequentially, on the same cells, mitochondrial activity (XTT), membrane integrity (neutral red test) and total cell density (crystal violet dye exclusion test). Results from each test were compared by two-way analysis of variance (ANOVA). Results: Statistical analysis showed that whole milk, HBSS and soy milk were the most effective media in maintaining cell viability at all tested times (P < 0.05). The least amount of viable cells was observed when using coconut water. Conclusions: This study shows that the efficacy of soy milk in maintaining the viability of 3T3 fibroblasts is similar to that of HBSS and milk, as shown by three different cell viability tests.29431932

LARVA MIGRANS THAT AFFECT THE MOUTH

As air travel expands, tropical diseases are increasingly likely to be encountered. We report.a case of a nematode infection from dogs and cats that appeared in the mouth as larva migrans, and we review the literature.77436236

Analysis of the Contribution of Nonresident Progenitor Cells and Hematopoietic Cells to Reparative Dentinogenesis Using Parabiosis Model in Mice

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Introduction: The aim of this study was to analyze the contribution of nonresident progenitor/stem cells and hematopoietic cells to reparative dentinogenesis. Methods: Parabiosis was established between C57BL/6-TgN(ACTbEGFP)10sb/J transgenic mice (GFP+) and C57BL/6 wild-type mice (GFP-) to ensure blood cross-circulation between animals. Reparative dentinogenesis was stimulated by pulp exposures and capping on the first maxillary molar in the GFP- mice. Histologic sections of injured molars from GFP- Mice were analyzed by epifluorescence microscopy to examine the contributions of GFP+ cells (nonresident progenitor cells and hematopoietic cells originating from GFP+ mice) to reparative dentinogenesis. Results: GFP+ cells were detected in close association with reparative dentin formed at the site of pulp exposure in the maxillary first molars of the GFP- mice. Conclusions: The present study suggests the participation of the nonresident progenitor cells and hematopoietic cells in reparative dentinogenesis. (J Endod 2012;38:1214-1219)38912141219American Association of Endodontists FoundationCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)NIH [DE016689]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPES [3422/09-7]NIH [DE016689