Analysis of the cytotoxicity and bioactivity of CeraSeal, BioRoot™ and AH Plus® sealers in pre-osteoblast lineage cells.

BACKGROUND: The objective of the present study was to evaluate in vitro the cytotoxicity and bioactivity of various endodontic sealers (CeraSeal, BioRoot™ and AH Plus®) in pre-osteoblast mouse cells (MC3T3 cells). METHODS: MC3T3 cells (ATCC CRL-2594) were plated in 1 × 104 cells/well in 96-well plates in contact with endodontic sealers at concentrations of 1:10 and 1:100. Cell viability was evaluated by MTT assay after 24 and 48 h. In addition, sealer bioactivity was measured by RT-PCR for mediator of inflammation (Tnf, Ptgs2) and mineralization (Runx2, Msx1, Ssp1 and Dmp1) after 24 h and by Alizarin Red S Assay of mineralization after 28 days. Data were analyzed using one-way ANOVA followed by the Tukey's post-test at a significance level of 5%. RESULTS: BioRoot™ presented 24-hour cytotoxicity (p < 0.05) at 1:10 concentration. In the period of 48 h, no endodontic cement was cytotoxic to the cells compared to the control (p > 0.05). TNF-α gene expression was induced by AH Plus® (p < 0.05), while Ptgs2 was induced by the CeraSeal and BioRoot™ (p < 0.05). The expression of Runx2 was stimulated by BioRoot™ and AH Plus® (p < 0.05). In contrast, the expression of Dmp-1 Dmp1 was higher for the CeraSeal and BioRoot™ (p < 0.05). Nonetheless, the sealers did not impact the formation of mineralization nodules (p > 0.05). CONCLUSION: CeraSeal, BioRoot™ and AH Plus® sealers were not cytotoxic to MC3T3 cells within 48 h, but differentially induced the expression of genes related to inflammation and mineralization without impacting biomineralization by the cells.

In silico toxicity and immunological interactions of components of calcium silicate-based and epoxy resin-based endodontic sealers.

OBJECTIVES: The present study aimed to determine in silico toxicity predictions of test compounds from hydraulic calcium silicate-based sealers (HCSBS) and AH Plus and computationally simulate the interaction between these substances and mediators of periapical inflammation via molecular docking. MATERIALS AND METHODS: All chemical information of the test compounds was obtained from the PubChem site. Predictions for bioavailability and toxicity analyses were determined by the Molinspiration Cheminformatics, pkCSM, ProTox-II and OSIRIS Property Explorer platforms. Molecular docking was performed using the Autodock4 AMDock v.1.5.2 program to analyse interactions between proteins (IL-1ß, IL-6, IL-8, IL-10 and TNF-α) and ligands (calcium silicate hydrate, zirconium oxide, bisphenol-A epoxy resin, dibenzylamine, iron oxide and calcium tungstate) to establish the affinity and bonding mode between systems. RESULTS: Bisphenol-A epoxy resin had the lowest maximum dose tolerated in humans and was the test compound with the largest number of toxicological properties (hepatotoxicity, carcinogenicity and irritant). All systems had favourable molecular docking. However, the ligands bisphenol-A epoxy resin and dibenzylamine had the greatest affinity with the cytokines tested. CONCLUSION: In silico predictions and molecular docking pointed the higher toxicity and greater interaction with mediators of periapical inflammation of the main test compounds from AH Plus compared to those from HCSBS. CLINICAL RELEVANCE: This is the first in silico study involving endodontic materials and may serve as the basis for further research that can generate more data, producing knowledge on the interference of each chemical compound in the composition of different root canal sealers.

A critical analysis of research methods and experimental models to study biocompatibility of endodontic materials.

Materials used for endodontics and with direct contact to tissues have a wide range of indications, from vital pulpal treatments to root filling materials and those used in endodontic surgery. In principle, interaction with dental materials may result in damage to tissues locally or systemically. Thus, a great variety of test methods are applied to evaluate a materials' potential risk of adverse biological effects to ensure their biocompatibility before commercialization. However, the results of biocompatibility evaluations are dependent on not only the tested materials but also the test methods due to the diversity of these effects and numerous variables involved. In addition, diverse biological effects require equally diverse assessments on a structured and planned approach. Such a structured assessment of the materials consists of four phases: general toxicity, local tissue irritation, pre-clinical tests and clinical evaluations. Various types of screening assays are available; it is imperative to understand their advantages and limitations to recognize their appropriateness and for an accurate interpretation of their results. Recent scientific advances are rapidly introducing new materials to endodontics including nanomaterials, gene therapy and tissue engineering biomaterials. These new modalities open a new era to restore and regenerate dental tissues; however, all these new technologies can also present new hazards to patients. Before any clinical usage, new materials must be proven to be safe and not hazardous to health. Certain international standards exist for safety evaluation of dental materials (ISO 10993 series, ISO 7405 and ISO 14155-1), but researchers often fail to follow these standards due to lack of access to standards, limitation of the guidelines and complexity of new experimental methods, which may cause technical errors. Moreover, many laboratories have developed their testing strategy for biocompatibility, which makes any comparison between findings more difficult. The purpose of this review was to discuss the concept of biocompatibility, structured test programmes and international standards for testing the biocompatibility of endodontic material biocompatibility. The text will further detail current test methods for evaluating the biocompatibility of endodontic materials, and their advantages and limitations.

The evaluation of cytotoxicity and cytokine IL-6 production of root canal sealers with and without the incorporation of simvastatin: an invitro study.

BACKGROUND: Freshly mixed root canal sealers when proximate the periapical tissues, trigger varying degrees of cytotoxicity/inflammatory reactions. Simvastatin, a class of the drug statin, is a widely used cholesterol-lowering agent with additional anti-inflammatory activities. This study assessed the effects of simvastatin on cytotoxicity and the release of IL-6 (Interleukin-6) production when incorporated in zinc oxide eugenol and methacrylate resin-based sealers. METHODS: Experimental groups consisted of conventional zinc oxide eugenol and methacrylate based-EndoREZ sealers (ZE & ER respectively) and 0.5 mg/mL simvastatin incorporated sealers (ZES & ERS). L929 mouse fibroblast cells were exposed to freshly mixed experimental sealers and evaluated for cytotoxicity (MTT assay) and inflammation levels (inflammatory marker IL-6 for ELISA) at various time intervals (0h, 24h and 7th day). The values were compared to the cell control (CC; L929 cells alone) and solvent control (SC; L929 cells + DMSO) groups. All the experiments were conducted in triplicates and subjected to statistical analysis using IBM SPSS Statistics software. Non parametric tests were conducted using Kruskal-Wallis and Friedman tests for inter-group and intra-group comparisons respectively. Pairwise comparison was conducted by post hoc Dunn test followed by Bonferroni correction. P values < 0.05 were considered statistically significant. RESULTS: All the experimental groups (ZE, ER, ZES, ERS) exhibited varying degree of cytotoxicity and IL-6 expression compared to the control groups CC and SC. The cell viability for ZE and ER decreased on day 7 as compared to 24 h. ZES and ERS had higher viable cells (75.93% & 79.90%) compared to ZE and ER (54.39% & 57.84%) at all time periods. Increased expression of IL-6 was observed in ZE & ER (25.49 pg/mL & 23.14 pg/mL) when compared to simvastatin incorporated ZE & ER (ZES-12.70 pg/mL & ERS-14.68 pg/mL) at all time periods. Highest level of cytotoxicity and inflammation was observed in ZE compared to all the other groups on day 7. CONCLUSIONS: Addition of 0.5 mg/mL of simvastatin to the sealers (ZES and ERS) decreased the cytotoxicity in the freshly mixed state and reduces their inflammatory effect.

Investigation of a modified hydraulic calcium silicate-based material - Bio-C Pulpo

Abstract This study evaluated the physicochemical, biological, and antimicrobial properties of a new hydraulic calcium silicate-based modified material, and compared it with MTA Repair HP and MTA Angelus. The materials were assessed regarding color luminosity (L), color change, radiopacity, setting time, and ISO 6876:2012 linear flow. Volumetric filling and volume change were evaluated using microcomputed-tomography (µCT). Chemical characterization after 28 days in Hank's Balanced Salt Solution (HBSS) and pH analysis were also assessed. Biological characterization of cytotoxicity and microbiological assessment were also undertaken. Shapiro-Wilk, ANOVA, Levene and post hoc analyses with Bonferroni correction were performed, adopting a 5% significance level (p <0.05). Bio-C Pulpo exhibited the highest L values after 90 days. All tested materials demonstrated color change during the analyses, and had radiopacity above 5 mm Al. MTA Repair HP set faster than Bio-C Pulpo, whereas the latter had the highest linear flow. MTA Repair HP had the highest volumetric filling in µCT analysis. Bio-C Pulpo showed the highest alkalinity during all tested periods, and the highest volumetric loss (above 9%), in comparison with MTA Repair HP and MTA Angelus. Bio-C Pulpo did not form calcium hydroxide after hydration. MTA Repair HP demonstrated the highest cytocompatibility, and Bio-C Pulpo, the highest cytotoxicity. No inhibition halos were observed for any material, and similar higher turbidity values were seen after direct contact. Composition additives used in Bio-C Pulpo modified its properties, and both the absence of calcium hydroxide deposition after hydration, and the related cytotoxicity of this material are of particular concern.

Cytotoxicity, and antimicrobial and physicochemical properties of sealers incorporated with Uncaria tomentosa

Abstract This study evaluated the cytotoxicity, the antimicrobial and physicochemical properties of root canal sealers incorporated with phytotherapic Uncaria tomentosa (UT). Unmodified AH Plus (Dentsply, DeTrey, Germany) and MTA Fillapex (Angelus, Londrina, Brazil) were used as controls. UT was incorporated into AH Plus and MTA Fillapex, at concentrations of 2% and 5% of the total weight of these sealers (w/w). Flowability, setting time, and solubility were evaluated following ISO requirements. The pH values were measured at periods of 12, 24, 48 hours, and 7 days. The antimicrobial activity of the sealers against Enterococcus faecalis was analyzed by both direct contact tests in freshly prepared sealers, and after 7 days. The cytotoxicity of the samples was evaluated by the MTT assay, to check Balb/c 3T3 cell viability. The statistical analysis was performed by one-way ANOVA and Tukey's test (p < 0.05). The incorporation of UT was associated with a decrease in flow, for both sealers, an increase in AH Plus setting time, increase in MTA Fillapex pH values, and solubility (after 14 days), for both sealers (p < 0.05). Regarding the antibacterial evaluation, bacterial reduction was reported after incorporation of UT into both AH Plus and MTA Fillapex, up to 7 days after handling of the material (P<0.05). UT incorporation decreased the cytotoxic effects of both AH Plus and MTA Fillapex sealers in a way directly proportional to their respective concentrations (p < 0.05). In conclusion, UT can be added to both sealers to reduce their cytotoxicity, and improve their antibacterial effects, without compromising their original physicochemical properties.

Evaluación de la citotoxicidad de Biodentine, IRM y MTA en cultivos de fibroblastos del ligamento periodontal humano / An evaluation of the cytotoxicity of Biodentine, IRM and MTA in cultures of human periodontal ligament fibroblasts

Introducción: Los materiales para la obturación retrógrada son diversos. Actualmente, IRM y MTA son las alternativas clínicas más utilizadas, no obstante, es relativamente reciente la introducción de materiales a base de silicatos tricálcicos tal como Biodentine. Objetivo: Determinar la citotoxicidad de fibroblastos del ligamento periodontal humano expuestos a medios de cultivo condicionados con Biodentine, IRM y MTA. Material y métodos: 1 × 103 fibroblastos del ligamento periodontal humano fueron expuestos a medios DMEM/F12 condicionados con MTA, IRM y Biodentine en tres protocolos diferentes. Se realizó un ensayo de MTT para determinar la viabilidad celular a las cero, 24, 48, 72 horas, siete y 14 días. Se realizó una prueba ANOVA (p < 0.05). Resultados: En los tres protocolos con los diferentes medios de cultivo condicionados, la viabilidad de las células fue predominantemente proliferativa; sin embargo, las células expuestas a Biodentine mostraron una tendencia mayor que la MTA o la IRM. Conclusión: Las células expuestas a la Biodentine mostraron un comportamiento proliferativo a los 14 días de análisis. Se debe realizar más investigación a nivel in vivo y clínico para obtener más información sobre la conducta de estos materiales empleados para la obturación retrógrada (AU)

Introduction: The materials for retrograde filling are diverse. Currently, IRM and MTA are the most commonly used clinical alternatives, however, the introduction of materials based on tricalcium silicates such as Biodentine is relatively recent. Objective: To determine the cytotoxicity of human periodontal ligament fibroblasts exposed to culture media conditioned with Biodentine, IRM and MTA. Material and methods: 1 × 103 fibroblasts of the human periodontal ligament were exposed to DMEM/F12 media conditioned with MTA, IRM and Biodentine in 3 different protocols. An MTT assay was performed to determine cell viability at 0, 24, 48, 72 hours, seven and 14 days. An ANOVA test was performed (p < 0.05). Results: In the three protocols with the different conditioned culture media, the viability of the cells was predominantly proliferative, however, the cells exposed to Biodentine showed a higher tendency than the MTA or the IRM. Conclusion: The cells exposed to the Biodentine showed a proliferative behavior at 14 days of analysis. More research should be done at in vivo and clinical level to obtain more information about the behavior of these materials used for retrograde filling (AU)

Cytotoxicity, Cell Adhesion, and Apoptotic Gene Expression in Periodontal Ligament Fibroblasts treated with Endodontic Sealers.

OBJECTIVE: The present study assessed cytotoxicity, cell adhesion, and apoptotic gene expression in periodontal ligament fibroblasts (PLF) treated with 2 endodontic sealers. METHODS: PLF cells were obtained from nonerupted third molars and cultured. MTS and LIVE/DEAD assays were performed using different treatments and time periods. Cellular adhesion was evaluated using immunocytochemistry for integrin ß1 and vinculin expression, and the gene expressions of nuclear factor kB (NF-кB), P53, and apoptotic protease-activating factor 1 (Apaf-1) were evaluated using PCR. RESULTS: Cell proliferation at 12, 24, and 48 h was statistically significant in the control and PLF groups receiving different treatments; PLF treated with culture medium containing non-hardened (NH) sealers showed a decrease in the number of cells. PLF treated with culture medium containing hardened (H) sealers also exhibited a decreased cell population. Integrin ß1 and vinculin were expressed in both cell cultures treated with Acroseal (NH and H); however, the cell morphology changed and the cell population decreased. The gene expression of NF-kB and that of P53 were significantly different between the control group and the groups treated with the different sealers; mineral trioxide aggregate (MTA) (NH and H) inhibited Apaf-1, and PLF treated with Acroseal H exhibited increased Apaf-1 expression. CONCLUSION: Both sealers showed a certain level of cytotoxicity. The gene expression of NF-κB and P53 in PLF treated with the sealers showed significant changes compared to that of the control group, and MTA inhibited Apaf-1.

Cytotoxicity and biocompatibility of a new bioceramic endodontic sealer containing calcium hydroxide

Abstract: This study evaluated the cytotoxicity and biocompatibility of a new bioceramic endodontic sealer (i.e., Sealer Plus BC) in comparison with those of MTA Fillapex and AH Plus. L929 fibroblasts were cultured and Alamar Blue was used to evaluate cell viability of diluted extracts (1:50, 1:100, and 1:200) from each sealer at 24 h. Polyethylene tubes that were filled with material or empty (as a control) were implanted in the subcutaneous tissue of rats. The rats were killed after 7 and 30 d (n = 8), and the tubes were removed for histological analysis. Parametric data was analyzed using a one-way ANOVA test, and nonparametric data was analyzed via the Kruskal-Wallis test followed by the Dunn test (p < 0.05). A reduction in cell viability was observed in the extracts that were more diluted for Sealer Plus BC when compared to that of Control and AH Plus (p < 0.05). However, the 1:50 dilution of the Sealer Plus BC was similar to that of the Control (p > 0.05). Conversely, more diluted extracts of MTA Fillapex (1:200) and AH Plus (1:100 and 1:200) were similar to the Control (p > 0.05). Histological analysis performed at 7 d did not indicate any significant difference between tissue response for all materials, and the fibrous capsule was thick (p > 0.05). At 30 d, Sealer Plus BC was similar to the Control (p > 0.05) and MTA Fillapex and AH Plus exhibited greater inflammation than the Control (p < 0.05). The fibrous capsule was thin for the Control and for most specimens of Sealer Plus BC and AH Plus. Thus, Sealer Plus BC is biocompatible when compared to MTA Fillapex and AH Plus, and it is less cytotoxic when less-diluted extracts are used.

Leachables and cytotoxicity of root canal sealers.

This in vitro study aimed to detect leaching components from an epoxy resin- and a methacrylate-based endodontic sealer and correlate them to cytotoxicity induced by material extracts for up to 36 weeks. We qualitatively determined the substances released by aged AH Plus and RealSeal SE specimens at seven intervals between 0 and 36 weeks. Quantification was performed by ultra-performance liquid chromatography/mass spectrometry (UPLC/MS). We determined the viability of murine macrophage J774 cells after 24 h exposure to material extracts, at each interval, using a fluorescence staining/microscopy method. The leachables detected were 1-adamantylamine and bisphenol A diglycidyl ether from AH Plus and N-(p-tolyl) diethanolamine and caprolactone-2-(methacryloyloxy) ethyl ester from RealSeal SE. The largest UPLC/MS chromatogram peak areas of the leachables were detected within 72 h. Induction of cytotoxicity after exposure to AH Plus and RealSeal SE extracts coincided with leachant detected within the first 72 and 24 h, respectively. The clinical impact of the cytotoxicity due to resin-based endodontic sealers is unknown.

Novel endodontic sealers induced satisfactory tissue response in mice.

OBJECTIVES: The aim of this study was to evaluate the subcutaneous response induced by Roeko Guttaflow2 (RG), Sealapex Xpress (SX), AH Plus (AHP) sealers. METHODS: 100 BALB/c mice received implants in the subcutaneous tissue with the tested materials (10 animals per period for each evaluated sealer) and were evaluated after different experimental periods (7, 21 and 63 days), in each animal was placed a tube, the control group was an empty tube. Histological analysis evaluated semi-quantitatively the inflammatory infiltration, collagen fiber formation and tissue thickness. In addition, immunohistochemistry was performed for interleukin-6 (IL-6). Data were statistically analyzed (α = 0.05). RESULTS: RG promoted a greater collagen fiber formation at 7 days and 63 days compared to the CG (p = 0.004) and AHP (p = 0.005) respectively, while at 21 days, the SX promoted a greater reaction (p = 0.021). For the tissue thickness, there was a greater reaction at 7 days with CG (p = 0.0156) and with RG at 63 days (p = 0.03). Regarding the inflammatory infiltrate, there was no difference at 7 days and 63 days (p = 0.5; p = 0.27), while at 21 days, a statistically difference was found between SX, CG (p = 0.04) and RG (p = 0.027). In addition, the presence of IL-6 was observed in almost all groups, with a more intense marking at 7days. SIGNIFICANCE: All cements evaluated presented a satisfactory tissue response, however, RG was the one that presented a more satisfactory tissue response.

Cytotoxicity Evaluation of Root Canal Sealers Using an In Vitro Experimental Model with Roots

Abstract The aim of the present study was to evaluate the cytotoxicity of root canal sealers under conditions closely resembling a clinical reality. A primary human fibroblast cell line was seeded in 24-well acrylic plates with Dulbecco’s modified Eagle’s medium supplemented with 10% serum fetal bovine (SFB) and incubated for 24 h. Root canals from premolars were filled and individually attached to nylon devices to be stabilized in the wells with the already seeded cells. Specimens were divided into groups as follows: Control: gutta-percha cones (GPC); AH Plus+GPC; Sealapex+GPC; MTA Fillapex+GPC and Endofill+GPC. After 24 and 48 h, cell viability and morphology were evaluated by MTT assay and scanning electron microscopy (SEM), respectively. Statistical analysis was performed by Mann-Whitney test, complemented by Kruskal Wallis test (p<0.05). Only Endofill presented cytotoxicity after 24 h. MTA Fillapex and Endofill reduced the production of succinic desidrogenase after 48 h. AH Plus was non-toxic at any time point. SEM showed that the AH Plus and MTA Fillapex groups presented fibroblasts with morphology close to the control group, while the Endofill group presented few cells with thin extensions cells. The present study showed that good results were present in AH Plus and Sealapex, but not the Endofill group after 48 h. The method used enabled evaluation of the cytotoxicity of the studied sealers that diffused through the root apex.

Resumo O objetivo do presente estudo foi avaliar a citotoxicidade dos cimentos dos canais radiculares em condições próximas à realidade clinica. Uma linhagem primária de fibrolastos humanos foi semeada em placas acrílicas de 24-poços com meio de cultura Dulbecco’s modified Eagle’s medium suplementado com 10% de soro fetal bovino e incubados por 24 h. Os canais radiculares de pré-molares foram obturados e individualmente adaptados aos dispositivos de nylon para serem estabilizados nos poços com as células já semeadas. Amostras foram dividas de acordo com os grupos: Controle: cones de gutta-percha (CGP); AH Plus+CGP; Sealapex+CGP; MTA Fillapex+CGP e Endofill+CGP. Após 24 e 48 h, a viabilidade e a morfologia celular foram avaliadas pelo ensaio de MTT e microscopia eletrônica de varredura (MEV), respectivamente. Análises estatísticas foram realizadas pelo teste de Mann-Whitney, complementadas por Kruskal Wallis (p<0,05). Apenas o Endofill apresentou citotoxicidade após 24 h. MTA Fillapex e Endofill reduziram a produção da enzima desidrogenase succinica após 48 h. AH Plus não apresentou toxicidade em nenhum momento. MEV mostrou que os grupos AH Plus e o MTA Fillapex apresentaram fibroblastos com morfologia próxima ao grupo controle, enquanto que o grupo do Endofill apresentou poucas células com finos prolongamentos. O presente estudo demonstrou que resultados satisfatórios foram apresentados nos grupos AH Plus e Sealapex, mas não para o Endofill após 48 h. O método utilizado permitiu avaliar a citotoxicidade dos cimentos que se difundem pelo ápice radicular.

Physical-chemical properties and cytotoxicity analysis of 5 different endodontic sealers / Propriedades físico-químicas e análise da citotoxicidade de 5 diferentes cimentos endodônticos

The aim of this study was to analyze the radiopacity, setting time, flowability, pH, calcium ion release, solubility and cytotoxicity of bioceramic cements Totalfill BC Sealer and Totalfill BC RRM, and compare them with AH Plus, MTA Fillapex and MTA Angelus. The groups were divided and compared among them according to the filling and retro-filling cement functions. Totalfill BC Sealer was compared with AH Plus and MTA Fillapex; and Totalfill BC RRM retrofilling cement with MTA Angelus. For radiopacity analysis, specimens were placed in metal rings measuring 10x1 mm placed on occlusal film together with the aluminum scale. Digora 1.51 software was used to evaluate the digitized images and determine radiographic density. Setting time was tested in accordance with the American Society for Testing and Materials C266-08 standard specifications, but specimens were fabricated in accordance with the International Organization for Standardization 6876: 2001. Flow was tested in accordance with ANSI/ADA No.57/200 specifications. In total 30 acrylic teeth were filled with filling-cements and 20, with (retrograde cavity) retro-filling cements. All teeth were immersed in ultrapure water for pH and calcium ion release measurement (atomic absorption spectrophotometer) for time intervals of 1, 3, 24, 72, 168 and 360 hours. Solubility was tested by scanning and digitizing 50 acrylic teeth twice by Micro- CT, before and after immersion in ultrapure water for time intervals of 168, 360 and 720 hours. The images were reconstructed and volume (mm3) values of samples obtained by means of CTan software (CTan v1.11.10.0, SkyScan). The in vitro effects on cells were analyzed at concentrations of 100, 50, 10, 5, 1 mg/mL, and 0 mg / mLnegative control group and recorded in time intervals of 24, 48 and 72 hours by MTT reduction assay. The results were statistically analyzed by the ANOVA, Tukey, Kruskal-Wallis and Dunn tests (P<0.05). All radiopacity values according to ISO 6876/2001, AH Plus (7.86 mm Al) being the most radiopaque followed by Totalfill BC Sealer (4.84 mm Al), MTA Fillapex (3.41 mm Al), Totalfill BC RRM (6.8 mm Al), and MTA Angelus (6.7 mm Al). The following values were the initial and final setting time (in hours), respectively: AH Plus (8 and 15); Totalfill BC Sealer (11 and 24); MTA Fillapex (13 and 26); MTA Angelus (10 and 120 minutes) and Totalfill BC RRM (3 hours and 22 hours). In flow analysis, the cements behaved as follows: MTA Fillapex (47 mm), Totalfill BC Sealer (41.5 mm), Totalfill BC RRM (33.5 mm), AH Plus (33 mm) e MTA Angelus (17.5 mm) (p < 0.05). pH analysis showed in general the lowest values for AH Plus cement, followed by Totalfill BC RRM, MTA Angelus, MTA Fillapex and Totalfill BC Sealer. AH Plus showed the highest Ca2+ release in time interval 1 hour (1.38 mg/L); MTA Fillapex, in 360 hours (3.81 mg/L); MTA Angelus, 1 hour (1.38 mg/L); Totalfill BC Sealer, 360 hours (6.77 mg/L) and Totalfill BC RRM, 360 hours (3.81 mg/L). Almost all the sealers presented solubility lower than 3% in all periods, as recommended by ISO 6876/2001. Whereas, the MTA Fillapex solubility value was higher than 5% in all periods. Relative to cytotoxicity, all the cements were shown to be toxic at the concentration of 100 mg/mL, however, Totalfill BC Sealer and Totalfill BC RRM showed the best cell viability result compared with the other cements tested. We concluded that all root canal filling and root retro-filling complied with the requisites of radiopacity, setting time, flow, pH, calcium ion release, solubility and cytotoxicity. With the exception of the MTA Fillapex that not only fulfilled the requirement of solubility. Of the sealers, Totalfill BC Sealer was outstanding: it showed the highest pH and Ca2+ release, and lowest cytotoxicity. Among the retrofilling cements, Totalfill BC RRM maintained its high pH, higher Ca2+ release, and lower cytotoxicity. (AU)

O objetivo do presente estudo foi analisar a radiopacidade, tempo de presa, escoamento, pH, liberação de íons cálcio, solubilidade e citotoxicidade dos cimentos biocerâmicos Totalfill BC Sealer e Totalfill BC RRM e compará-los ao AH Plus, MTA Fillapex e MTA Angelus. Os grupos foram divididos e comparados entre si de acordo com as funções dos cimentos de obturação e retro-obturação. Comparamos o cimento obturador Totalfill BC Sealer com os cimentos AH Plus e MTA Filapex, e o cimento retrobturador Totalfill BC RRM com o cimento retrobturador MTA Angelus. Para análise da radiopacidade, os espécimes foram colocados em anéis metálicos medindo 10x1 mm, dispostos sobre um filme oclusal com uma escala de alumínio. O software Digora 1.51 foi utilizado para avaliar as imagens digitalizadas e determinar a densidade radiográfica. O tempo de presa foi realizado de acordo com as especificações da American Society for Testing and Materials C266-08 standard specifications, mas os espécimes foram feitos de acordo com a International Organization for Standardization 6876: 2001. O escoamento foi realizado de acordo com as especificações ANSI/ADA N0 57/2000. Trinta dentes acrílicos foram preenchidos com cimentos obturadores e vinte dentes de acrílico (com cavidade retrógrada) foram preenchidos com cimentos retro-obturadores e imersos em água ultrapura para mensuração do pH e liberação de íons cálcio (espectrofotômetro de absorção atômica) no período de 1, 3, 24, 72, 168 e 360 horas. Para o teste de solubilidade, foram escaneados 50 dentes acrílicos e digitalizados duas vezes pelo Micro-CT, antes e após a imersão em água ultrapura nos períodos de 168, 360 e 720 horas. As imagens foram reconstruídas e o volume (mm3) das amostras foi obtido usando o software CTan (CTan v1.11.10.0, SkyScan). Os efeitos celulares in vitro foram analisados nas concentrações de 100, 50, 10, 5, 1 mg/mL e 0 mg / mLgrupo controle negativo e registados nos períodos de 24, 48 e 72 horas através do ensaio de redução de MTT. Os resultados foram analisados estatisticamente pelos testes ANOVA, Tukey, Kruskal-Wallis e Dunn (p < 0.05). Todos os valores de radiopacidade estavam de acordo com a norma ISO 6876/2001, sendo o AH Plus (7.86 mm Al) o mais radiopaco seguido dos demais cimentos; Totalfill BC Sealer (4.84 mm Al), MTA Filapex (3.41 mm Al), Totalfill BC RRM (6,8 mm Al), MTA Angelus (6,7 mm Al). Os valores obtidos para o tempo de presa inicial e final foram respectivamente, AH Plus (8 e 15 horas), Totalfill BC Sealer (11 e 24 horas), MTA Filapex (13 e 26 horas), Totalfill BC RRM (3 horas e 22 horas) e MTA Angelus (10 e 120 minutos). Na análise de escoamento os cimentos se comportaram da seguinte forma: AH Plus (33 mm), MTA Filapex (47 mm), Totalfill BC Sealer (41,5 mm), Totalfill BC RRM (33,5 mm), e MTA Angelus (17,5 mm) (p < 0.05). A análise do pH mostrou que o cimento AH Plus de um modo geral, foi o que apresentou os menores valores, seguido do Totalfill BC RRM, MTA Angelus, MTA Filapex e Totalfill BC Sealer. A maior liberação de Ca2+ do AH Plus foi no período de 1 hora (1.38 mg/L), MTA Filapex foi em 360 horas (3.81 mg/L), Totalfill BC Sealer 360 horas (6.77 mg/L), Totalfill BC RRM 360 horas (3.81 mg/L) e MTA Angelus em 1 hora (1.38 mg/L). Todos os cimentos apresentaram solubilidade menor que 3% em todos os períodos, como recomendado pela ISO 6876/2001. Entretanto, os valores de solubilidade do MTA Fillapex excedeu mais que 5% em todos os períodos. Com relação à citotoxicidade, todos os cimentos mostraram-se tóxicos na concentração de 100 mg/mL, porém o Totalfill BC Sealer e Totalfill BC RRM apresentaram melhor resultado de viabilidade celular comparado aos demais cimentos testados. Concluiu-se que os cimentos de obturação e retro-obturação cumpriram os requisitos de radiopacidade, tempo de presa, escomento, pH, liberação de íons cálcio, solubilidade e citotoxicidade. Com exceção do MTA Fillapex que não cumpriu somente o requisito de solubilidade. Dos cimentos obturadores, o que melhor se portou foi o Totalfill BC Sealer, apresentando maior pH e liberação de íons cálcio e menor citotoxicidade. Dentre os cimentos retro-obturadores, Totalfill BC RRM foi o que melhor se destacou, mantendo seu pH elevado, possuindo maior liberação de Ca2+ e menor citotoxicidade. (AU)

Interaction of dental pulp stem cells with Biodentine and MTA after exposure to different environments

ABSTRACT Objective: The aim of the present study was to evaluate and compare the cytotoxic effects of Biodentine and MTA on dental pulp stem cells (DPSCs) and to assess cell viability and adherence after material exposure to an acidic environment. Material and Methods: DPSCs were cultured either alone or in contact with either: Biodentine; MTA set for 1 hour; or MTA set for 24 hours. After 4 and 7 days, cell viability was measured using the MTT assay. Biodentine and MTA were also prepared and packed into standardized bovine dentin disks and divided into three groups according to the storage media (n=6/group): freshly mixed materials without storage medium (Group A); materials stored in saline (Group B); materials stored in citric acid buffered at pH 5.4 (Group C). After 24 hours, DPSCs were introduced in the wells and cell adherence, viability, and cellular morphology were observed via confocal microscopy after three days of culture. Cell viability was analyzed using repeated-measures analysis of variance test with Tukey's post hoc tests (α=0.05). Results: Biodentine expressed significantly higher cell viability compared with all other groups after 4 days, with no differences after 7 days. Notably, cell viability was significantly greater in 24-hour set MTA compared with 1-hour set MTA and control groups after 7 days. Material exposure to an acidic environment showed an increase in cell adherence and viability in both groups. Conclusions: Biodentine induced a significantly accelerated cell proliferation compared with MTA. Setting of these materials in the presence of citric acid enhanced DPSC viability and adherence.

Evaluation of the genotoxicity and cytotoxicity of filling pastes used for pulp therapy on deciduous teeth using the micronucleus test on bone marrow from mice (Mus musculus).

Pulp therapy is the last resort for preserving deciduous teeth. However, the genotoxic and cytotoxic effects of many products used in this therapy are not well established. The aim of this study was to use the micronucleus test on bone marrow from mice to evaluate the genotoxic and cytotoxic effects of four filling pastes: zinc oxide, calcium hydroxide P.A., mineral trioxide aggregate and an iodoform paste (iodoform + camphorated + paramonochlorophenol + rifamycin + prednisolone). Male Swiss mice were divided into 4 groups of 10 animals, each exposed to one of the pastes, and were subdivided according to the dilutions tested: 1/10, 1/50, 1/500 and 1/1000 administered intraperitoneally (0.1ml/10g of weight). Cyclophosphamide was the positive control. The negative controls were dimethylsulfoxide and buffered saline solution. Five animals were killed 24h and five 48h after the treatment. The material was processed in accordance with Schmid (1976) and micronuclei were counted in 1000 polychromatic erythrocytes (PCE), under an optical microscope in a blinded test. Cytotoxicity was evaluated using the PCE/normochromatic erythrocyte (NCE) ratio in 200 erythrocytes. The micronucleus analysis results were evaluated using the conditional test for comparing proportions in situations of rare events. Analysis of variance and Tukey's test were used to evaluate the PCE/NCE ratio. There was significantly greater occurrence of micronuclei in the animals treated with iodoform paste at all the dilutions tested, at both sacrifice times. Greater occurrence of micronuclei was observed among the animals treated with zinc oxide and sacrificed 48h after the treatment, at the dilutions 1:50; 1:500 and 1:1000. Calcium hydroxide P.A. and mineral trioxide aggregate did not present any genotoxic or cytotoxic effects. The genotoxicity and cytotoxicity of zinc oxide and iodoform paste revealed here constitute an initial step towards their contraindication, but additional studies will be necessary in order to securely establish the risks involved in their use.

Cytotoxic effects of new MTA-based cement formulations on fibroblast-like MDPL-20 cells

Abstract The present study aimed at evaluating the cytotoxic effects of a novel cement called CER on periodontal fibroblast-like cells of mice (MDPL-20), in comparison with different formulations of Mineral Trioxide Aggregate (MTA), by means of the cell viability test (MTT) and cell morphology analysis. Thirty-two round-shaped samples were fabricated with the following cements: white MTA, white and gray CER and experimental white MTA. The samples were immersed in serum-free culture medium for 24 hours or 7 days (n = 16). The extracts (culture medium + components released from the cements) were applied for 24 hours to previously cultured cells (40.000 cells/cm2) in the wells of 24-well plates. Cells seeded in complete culture medium were used as a negative control. Cell viability was assessed using the MTT assay. Two samples of each cement were used for cell morphology analysis by Scanning Electron Microscopy (SEM). The extracts obtained at the 7-day period presented higher cytotoxicity compared with the 24-hour period (p < 0.05). The gray CER obtained at 24 hours presented the highest cytotoxic effect, whereas the experimental white MTA presented the lowest, similar to the control (p > 0.05). However, at the 7-day period, the experimental white MTA presented no significant difference in comparison with the other cements (p > 0.05). At the 7-day period, CER cement presented cytotoxic effects on fibroblast-like cells, similar to different MTA formulations. However, the immersion period in the culture medium influenced the cytotoxicity of the cements, which was greater for CER cement at 24 hours.

Analysis of radiopacity, pH and cytotoxicity of a new bioceramic material.

OBJECTIVE: RetroMTA® is a new hydraulic bioceramic indicated for pulp capping, perforations or root resorption repair, apexification and apical surgery. The aim of this study was to compare the radiopacity, pH variation and cytotoxicity of this material to ProRoot® MTA. MATERIAL AND METHODS: Mixed cements were exposed to a digital x-ray along with an aluminum stepwedge for the radiopacity assay. pH values were verified after incubation period of 3, 24, 48, 72 and 168 hours. The cytotoxicity of each cement was tested on human periodontal ligament fibroblasts using a multiparametric assay. Data analysis was performed using ANOVA and Tukey'spost hoc in GraphPad Prism. RESULTS: ProRoot® MTA had higher radiopacity than RetroMTA®(p<0.001). No significant differences were observed for the pH of the materials throughout experimental periods (p>0.05) although pH levels of both materials reduced over time. Both ProRoot® MTA and RetroMTA® allowed for significantly higher cell viability when compared with the positive control (p<0.001). No statistical difference was observed between ProRoot® MTA and RetroMTA® cytotoxicity level in all test parameters, except for the ProRoot® MTA 48-hour extract media in the NR assay (p<0.05). CONCLUSION: The current study provides new data about the physicochemical and biological properties of Retro® MTA concerning radiopacity, pH and cytotoxic effects on human periodontal ligaments cells. Based on our findings, RetroMTA® meets the radiopacity requirements standardized by ANSI/ADA number 572, and similar pH values and biocompatibility to ProRoot® MTA. Further studies should be performed to evaluate additional properties of this new material.

In Vitro Evaluation of ProRoot MTA, Biodentine, and MM-MTA on Human Alveolar Bone Marrow Stem Cells in Terms of Biocompatibility and Mineralization.

INTRODUCTION: Stem cell technology has been a great hope for the regeneration of cells of pulp-dentin complex and dental structures together with surrounding bone and periodontium. The main challenge in the regeneration process is a successful combination of stem cells and efficient inductors such as inductive biomaterials. In this regard, today, manufacturers propose novel tooth filling materials. The current study was aimed to compare the effect of ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), Biodentine (Septodont, Saint Maur des Fossés, France), and MM-MTA (Micro-Mega, Besançon Cedex, France) on the cell viability, hard tissue deposition capacity, and osteogenic differentiation of human bone marrow stem cells (hBMSCs) derived from mandibular bone. METHODS: Dental materials were packed into Teflon rings (Grover Corp, Milwaukee, WI) and placed on Transwell inserts (Corning, Corning, NY) to determine the toxicity of tooth filling materials by the 3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H tetrazolium assay on days 1, 3, 7, and 14; 20% dimethyl sulfoxide (DMSO) was used as a positive control for the toxicity assay. hBMSCs were characterized by their surface markers with mesenchymal stem cell antibodies. Teflon rings were cocultured with hBMSCs followed by the induction of osteogenic differentiation. The osteogenic differentiation of hBMSCs and hard tissue formation of the materials were evaluated by analyzing the messenger RNA expression levels of osteonectin, Runt-related transcription factor 2, and collagen type 1A by real-time polymerase chain reaction expression analysis, measurement of alkaline phosphatase activity, and visualization of calcium deposits by alizarin red staining. RESULTS: MTA, Biodentine, and MM-MTA did not exhibit a cytotoxic effect on hBMSCs after 14 days in culture. Even though all the materials significantly stimulate (P < .05) osteogenic differentiation of hBMSCs compared with the negative control, ProRoot MTA showed greater osteoinductivity than Biodentine or MM-MTA according to the messenger RNA expression, alkaline phosphatase, immunocytochemistry, and alizarin red staining data. CONCLUSIONS: All of the dental materials used in this study show the osteogenic differentiation potential of hBMSCs. Therefore, newly introduced MM-MTA can also be used as a material of choice in routine dental treatment.

Analysis of radiopacity, pH and cytotoxicity of a new bioceramic material

AbstractObjective RetroMTA® is a new hydraulic bioceramic indicated for pulp capping, perforations or root resorption repair, apexification and apical surgery. The aim of this study was to compare the radiopacity, pH variation and cytotoxicity of this material to ProRoot® MTA.Material and Methods Mixed cements were exposed to a digital x-ray along with an aluminum stepwedge for the radiopacity assay. pH values were verified after incubation period of 3, 24, 48, 72 and 168 hours. The cytotoxicity of each cement was tested on human periodontal ligament fibroblasts using a multiparametric assay. Data analysis was performed using ANOVA and Tukey’spost hoc in GraphPad Prism.Results ProRoot® MTA had higher radiopacity than RetroMTA®(p<0.001). No significant differences were observed for the pH of the materials throughout experimental periods (p>0.05) although pH levels of both materials reduced over time. Both ProRoot® MTA and RetroMTA® allowed for significantly higher cell viability when compared with the positive control (p<0.001). No statistical difference was observed between ProRoot® MTA and RetroMTA® cytotoxicity level in all test parameters, except for the ProRoot® MTA 48-hour extract media in the NR assay (p<0.05).Conclusion The current study provides new data about the physicochemical and biological properties of Retro® MTA concerning radiopacity, pH and cytotoxic effects on human periodontal ligaments cells. Based on our findings, RetroMTA® meets the radiopacity requirements standardized by ANSI/ADA number 572, and similar pH values and biocompatibility to ProRoot® MTA. Further studies should be performed to evaluate additional properties of this new material.

Assessment of the cytotoxicity of a mineral trioxide aggregate-based sealer with respect to macrophage activity.

AIM: To assess the influence of co-culture with mineral trioxide aggregate (MTA) and MTA Fillapex (FLPX) on the viability, adherence, and phagocytosis activity of peritoneal macrophages from two mouse strains. METHODOLOGY: Cellular viability, adherence, and phagocytosis of Saccharomyces boulardii were assayed in the presence of capillaries containing MTA and MTA Fillapex. The data were analyzed using parametric (Student's t) and non-parametric (Mann-Whitney) tests. RESULTS: FLPX was severely cytotoxic and decreased cell viability, adherence, and phagocytic activity of both macrophage subtypes. Cells that were treated with MTA Fillapex remained viable (>80%) for only 4 h after stimulation. Macrophages from C57BL/6 mice presented higher adherence and higher phagocytic activity compared with macrophages from BALB/c mice. CONCLUSION: Comparison of MTA and FLPX effects upon macrophages indicates that FLPX may impair macrophage activity and viability, while MTA seems to increase phagocytic activity.