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, 1×105 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 MTT 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

Push-out bond strength of MTA HP, a new high-plasticity calcium silicate-based cement

This study was designed to investigate the resistance to dislodgment provided by MTA HP, a new high-plasticity calcium silicate-based cement. Biodentine and White MTA Angelus were used as reference materials for comparison. Three discs 1 ± 0.1 mm thick were obtained from the middle third of the roots of 5 maxillary canines. Three 0.8-mm-wide holes were drilled on the axial surface of each root disc. Standardized irrigation was performed. Then the holes were dried with paper points and filled with one of the three tested cements. The filled dental slices were immersed in a phosphate-buffered saline (PBS) solution (pH 7.2) for 7 days before the push-out assessment. The Kruskal-Wallis test was applied to assess the effect of each endodontic cement on the push-out bond strength. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05. All specimens had measurable push-out values and no premature failure occurred. There were significant differences among the materials (p <0.05). The Biodentine specimens had the highest push-out bond strength values (p < 0.05). MTA HP had significantly higher bond strength than White MTA (p < 0.05). MTA HP showed better push-out bond strength than its predecessor, White MTA; however, Biodentine had higher dislodgment resistance than both MTA formulations301FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJE-26/010.001243/2015; E-26/201.491/201

Monitoring the effectiveness of root canal procedures on endotoxin levels found in teeth with chronic apical periodontitis

Objective: The aim of this study was to monitor the effectiveness of root canal procedures by using different irrigants and intracanal medication on endotoxin levels found in root canals of teeth with chronic apical periodontitis. Material and Methods: Thirty root canals of teeth with pulpal necrosis associated with periapical lesions were selected and randomly divided into groups according to the irrigants used: GI - 2.5% NaOCl, GII - 2% chlorhexidine (CHX) gel, and GIII - saline solution (SS) (all, n=10). Samples were collected with sterile/apyrogenic paper points before (S1) and after root canal instrumentation (S2), after use of 17% ethylenediaminetetraacetic acid (EDTA) (S3), and after 30 days of intracanal medication (Ca(OH)2+SS) (S4). A turbidimetric kinetic Limulus Amebocyte Lysate assay was used for endotoxin measurement. Results: Endotoxins were detected in 100% of the root canals investigated (30/30), with a median value of 18.70 EU/mL. After S2, significant median percentage reduction was observed in all groups, irrespective of the irrigant tested: 2.5% NaOCl (99.65%) (GI), 2% CHX (94.27%) (GII), and SS (96.79%) (GIII) (all p;0.05). Intracanal medication for 30 days was able to significantly reduce residual endotoxins: 2.5% NaOCl (90%) (GI), 2% CHX (88.8%) (GII), and SS (85.7%) (GIII,

Monitoring the effectiveness of root canal procedures on endotoxin levels found in teeth with chronic apical periodontitis

Objective: The aim of this study was to monitor the effectiveness of root canal procedures by using different irrigants and intracanal medication on endotoxin levels found in root canals of teeth with chronic apical periodontitis. Material and methods: Thirty root canals of teeth with pulpal necrosis associated with periapical lesions were selected and randomly divided into groups according to the irrigants used: GI - 2.5% NaOCl, GII - 2% chlorhexidine (CHX) gel, and GIII - saline solution (SS) (all, n=10). Samples were collected with sterile/apyrogenic paper points before (S1) and after root canal instrumentation (S2), after use of 17% ethylenediaminetetraacetic acid (EDTA) (S3), and after 30 days of intracanal medication (Ca(OH)2+SS) (S4). A turbidimetric kinetic Limulus Amebocyte Lysate assay was used for endotoxin measurement. Results: Endotoxins were detected in 100% of the root canals investigated (30/30), with a median value of 18.70 EU/mL. After S2, significant median percentage reduction was observed in all groups, irrespective of the irrigant tested: 2.5% NaOCl (99.65%) (GI), 2% CHX (94.27%) (GII), and SS (96.79%) (GIII) (all p0.05). Intracanal medication for 30 days was able to significantly reduce residual endotoxins: 2.5% NaOCl (90%) (GI), 2% CHX (88.8%) (GII), and SS (85.7%) (GIII, p<0.05). No differences were found in the endotoxin reduction when comparing S2 and S4 treatment groups. Conclusion: Our findings demonstrated the effectiveness of the mechanical action of the instruments along with the flow and backflow of irrigant enduring root canal instrumentation for the endotoxin removal from root canals of teeth with chronic apical periodontitis. Moreover, the use of intracanal medication for 30 days contributed for an improvement of endotoxin reduction226490495CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302575/2009-0sem informação13/02402- 9; 10/13743-3; 10/19136-1; 10/17877-4; 11/09047-

Influence of the apical enlargement size on the endotoxin level reduction of dental root canals

Gram-negative bacteria play an essential role in endodontic infections because they have virulence factors such as endotoxin. Due to its potential cytotoxic activity, special attention has been given to the removal/neutralization of this endotoxin in the root canal system. OBJECTIVE: The aim of this study was to evaluate the influence of the apical enlargement size (AES) by using rotary instruments on the endotoxin level reduction of dental root canals. MATERIAL AND METHODS: Forty root canals of the mandibular premolar teeth were used. Escherichia coli endotoxin (055: B55) was inoculated into thirty root canals. Ten teeth served as the negative control group. After the incubation period, the first endotoxin samples were collected from the root canals with a sterile/apyrogenic paper point for the analysis of the endotoxin units (EU/mL) present before instrumentation (S1). Specimen instrumentation was performed with the Mtwo® rotary system in the sequence 10/.04, 15/.05, 20/.06, 25/.06, 30/.05, 35/.04 and 40/.04. To monitor the effectiveness of increasing apical enlargement on endotoxin removal, the second endotoxin samples were collected from all the root canals after instrumentation with the following instruments: #25/.06- (S2); #30/.05- (S3); # 35/.04- (S4); and #40/.04- (S5). Limulus amebocyte lysate (LAL) was used to quantify the levels of endotoxin. The results were statistically compared by using repeated measures of ANOVA with post hoc Tukey testing. RESULTS: Increasing levels of endotoxin removal was achieved by large sized apical enlargement: S2 (AES #25/.06)- 89.2%, S3 (AES #30/.05)- 95.9%, S4 (AES #35/.04)- 97.8% and S5 (AES #40/.04)- 98.2%. Substantial reduction of endotoxin content was obtained in S4 and S5 compared to S2 (

Evaluation of cytotoxicity, antimicrobial activity and physicochemical properties of a calcium aluminate-based endodontic material

A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey's test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (P.05). Conclusion: Under these experimental conditions, we concluded that the calcium aluminate-based endodontic material EndoBinder demonstrated suitable biological and physicochemical properties, so it can be suggested as a material of choice in root resorption, perforations and root-end filling221616

Evaluation of cytotoxicity, antimicrobial activity and physicochemical properties of a calcium aluminate-based endodontic material

A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey`s test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>;.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (

In vitro evaluation of the antimicrobial activity of five root canal sealers

The aim of the present study was to analyze the antimicrobial properties of five endodontic sealers: Endo Fill, Endomethasone, Endomethasone N, Sealer 26 and AH-Plus, against the following microorganisms: Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus sanguis and Actinomyces naeslundii. The sealers were tested immediately, 24 h, 48 h and 7 days after manipulation.The direct contact method through the observation of the microbial growth in liquid medium and the agar diffusion test were used to evaluate the antimicrobial properties of the sealers. The results, in both methodologies used, showed that immediately after manipulation, Endo-Fill and Endomethasone demonstrated the highest antimicrobial activity, with no statistically significant difference between them. Sealer 26 demonstrated the lowest antimicrobial activity. At all other times after manipulation, there were no statistically significant differences among all the sealers tested. In conclusion, none of the sealers totally inhibited the growth of the microorganisms. Furthermore, the antimicrobial activity of each sealer decreased with time and was dependent upon the microbial susceptibility to them.O objetivo do presente estudo foi analisar as propriedades antimicrobianas de cinco cimentos endodônticos: Endo Fill, Endomethasone, Endomethasone N, Sealer 26 e AH-Plus, em diferentes períodos pós-manipulação, i.e., imediatamente e após 24 horas, 48 horas e 7 dias, contra os seguintes microrganismos: Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus sanguis e Actinomyces naeslundii. Os métodos usados foram o contato direto através da observação do crescimento microbiano em meio líquido e o teste de difusão em agar. Os resultados, nas duas metodologias usadas, mostraram que: 1) imediatamente após a manipulação, Endo-Fill e Endomethasone apresentaram a maior atividade antimicrobiana, sem diferenças estatisticamente significantes entre eles. Sealer 26 teve a menor atividade antimicrobiana; 2) nos outros tempos pós-manipulação, não houveram diferenças estatisticamente significantes entre os cimentos testados. Foi concluído que nenhum dos cimentos inibiu completamente o crescimento dos microrganismos testados. A atividade antimicrobiana de cada cimento diminuiu com o tempo e dependeu da suscetibilidade microbiana a eles.3035Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Antimicrobial and cytotoxic effects of phosphoric acid solution compared to other root canal irrigants

Phosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer. The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics. The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (solution and gel), and 5.25% NaOCl were evaluated. The antimicrobial activity was tested against Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Actinomyces meyeri, Parvimonas micra, Porphyromonas gingivalis, and Prevotella nigrescensaccording to the agar diffusion method. The cytotoxicity of the irrigants was determined by using the MTT assay. Phosphoric acid presented higher antimicrobial activity compared to the other tested irrigants. With regard to the cell viability, this solution showed results similar to those with 5.25% NaOCl and 2% chlorhexidine (gel and solution), whereas 17% EDTA and 10% citric acid showed higher cell viability compared to other irrigants. Phosphoric acid demonstrated higher antimicrobial activity and cytotoxicity similar to that of 5.25% NaOCl and 2% chlorhexidine (gel and solution).232158163CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302575/2009-0Sem informação2009/53976-0; 2010/50817-5; 2011/09047-

Surface Morphology Alterations In Bovine Dentin Exposed To Different Bleaching Agents

Aim: This study evaluated the morphological changes caused by internal bleaching agents on dentin surface. Methods: Twenty crowns of bovine incisors were cut into slabs that were randomly distributed in six experimental groups (n = 5), according to the bleaching agent used: G1 – sodium perborate + water, G2 – sodium perborate + 2% chlorhexidine gel, G3 – sodium perborate + 30% hydrogen peroxide, G4 – 30% hydrogen peroxide, G5 – 37% carbamide peroxide and G6 – gel base without carbamide. Two Control Groups were used: C1 with distilled water and C2 with 2% chlorhexidine gel. The specimens were immersed in the respective test bleaching agent and incubated at 37 °C for seven days. Following, they were prepared for scanning electron microscopy and five images from each tooth segment were recorded and analyzed for surface morphological alterations, by three previously calibrated examiners. Inter-examiner agreement was verified using the Kappa test. The rank averages obtained for the groups were subjected to Kruskal-Wallis analysis of variance at 5% significance level. Results: The analysis of the scores obtained indicated that all tested materials caused some morphological alteration on dentin, except for sodium perborate + water (G1) and Control Groups 1 and 2. Hydrogen peroxide and carbamide peroxide caused significantly more severe alterations (p < 0.05) to dentin structure, than the other bleaching agents evaluated. Conclusions: Sodium perborate-based pastes seemed to be the most harmless agent to dentin structures in non-vital tooth bleaching, while hydrogen peroxide solutions and carbamide peroxide agents caused the greatest alterations.8125-2