Pulp Canal Sealer EWT Research Articles

Bacterial Leakage Evaluation of Three Root Canal Sealers with Two Obturation Techniques: An in Vitro Study

Background: The purpose of this study was to compare the quality of the coronal seal of three root canal sealers and two obturation techniques using the bacterial penetration method. Methods and Results: A total of 132 single-rooted human teeth with fully developed apices were used. The teeth were randomly assigned to three experimental groups according to the endodontic sealer used. Group 1: Samples (n=44) were obturated using a zinc oxide eugenol-based sealer, Pulp Canal Sealer EWT. Group 2: Samples (n=44) were obturated using an epoxy resin-based sealer, AH Plus. Group 3: Samples (n=44) were obturated using a bioceramic-based root canal sealer, Well-Root ST. Each group was subdivided into 2 equal subgroups in accordance with the obturation technique being used: CLCT and ThOT. Thus, 6 subgroups were formed: Sub-1A: Pulp Canal Sealer/CLCT; Sub-2A: AH Plus/CLCT; Sub-3A: Well-ROOT ST/CLCT; Sub-1B: Pulp Canal Sealer/ThOT; Sub-2B: Ah Plus/ThOT; Sub-3B: Well-ROOT ST/ThOT. A dual-chamber device was used to evaluate bacterial leakage. Fresh medium and E. faecalis were added to the upper chamber every 4 days. The broth was monitored for color change daily for 33 days. Significant differences were found among Sub-2A vs. Sub-1B (P=0.023), Sub-1A vs. Sub-3A (P=0.014), Sub-1A vs. Sub-2B (P=0.024), Sub-1A vs. Sub-3B (P=0.002), Sub-3A vs. Sub-1B (P=0.003), Sub-2B vs. Sub-1B (P=0.005), and Sub-1B vs. Sub-3B (P<0.0001). There was no significant difference in the average occurrence of turbidity between CLCT and ThOT (P=0.718) Conclusion: Regardless of the obturation technique, all root canal sealers exhibited leakage; however, the bioceramic-based root canal sealer appeared to perform better than the epoxy resin-based sealer and the zinc oxide eugenol-based sealer.

Comparison of physico-chemical properties of zinc oxide eugenol cement and a bioceramic sealer.

The aim of the present study was to compare the physico-chemical properties of EssenSeal with AH PLUS bioceramic and Pulp Canal Sealer EWT. Flow, solubility, film thickness, radiopacity and setting time were evaluated according to ISO 6876 (2012) specifications. External and cross-section surface characteristics were analysed under a scanning electron microscope. Statistical analysis was performed using Shapiro-Wilk's test, one-way ANOVA and the Tukey HSD test. All the sealers conformed to the ISO 6876 (2012) standards, except for the setting time for AH plus bioceramic, which exceeded more than 10% of the time indicated by the manufacturer. Statistically significant differences were found between the three study sealers regarding the physico-chemical properties tested (p < 0.05). EssenSeal demonstrated characteristics respecting the ISO 6876 (2012) standards and can be considered a predictable alternative in root canal sealing.

Effectiveness of the REvision System and Sonic Irrigation in the Removal of Root Canal Filling Material from Oval Canals: An In Vitro Study.

This study aimed to evaluate the effectiveness of the Endostar REvision system (Poldent, Warsaw, Poland) in the removal of filling materials from oval root canals using sonic irrigation as an additional cleaning method. Thirty human-extracted mandibular premolars with oval canals were prepared using the ProTaper Universal system (Dentsply Maillefer, Ballaigues, Switzerland) up to instrument F1 (20/.07), and then filled by the continuous wave vertical compaction technique using pulp canal sealer EWT (Sybron Dental Specialties, Orange, CA, USA). The teeth were randomly divided into two groups (n = 15) according to the instrumentation system and the additional cleaning method, as follows: REvision (30/.08, 25/.06) with EQ-S sonic activation (Meta Biomed, Chungcheongbuk-do, Korea), REvision (30/.08, 25/.06) without additional activation. All specimens were sectioned longitudinally at 3 and 7 mm from the apex, and analyzed using digital microscopy (KEYENCE, Osaka, Japan) to measure the total area of the residual obturation materials, followed by SEM analysis. The data on the percentage of remaining filling material were analyzed by Kruskal–Wallis one-way Analysis of Variance on ranks. None of the retreatment protocols completely removed the filling material from the root canals (p > 0.05); the retreatment technique using sonic activation showed statistically less residual filling materials than the retreatment technique using irrigants without activation at the coronal third (p < 0.05), whilst no significant difference was found between both tested groups at the apical and middle thirds (p > 0.05). The REvision system showed promising results in the removal of filling materials from oval canals.

Antimicrobial Efficacy of Plant Extracts Combined with Endodontic Sealer on the Growth of Oral Pathogen - An In Vitro Study

Aim: The aim of this study is to evaluate the antimicrobial efficacy of synthetic sealing material (Zinc oxide eugenol based sealer- Pulp canal sealer EWT) and medicinal plant extracts (Glycyrrhiza glabra, Zingiber officinale, Cinnamon zeylanicum) individually and in combination against oral pathogen (Enterococcus faecalis). Methods: The herbal extracts were independently mixed in different ratios with zinc oxide powder, followed by mixing with eugenol to know the effective concentration using antibacterial assay. Different concentrations of each test material were placed into Agar diffusion wells and zones of inhibition were measured against the selected bacteria. The concentration with maximum zone of inhibition for each test material was assessed and grouped as group I- Glycyrrhiza glabra and pulp canal sealer EWT, group II-Zingiber officinale and pulp canal sealer EWT, group III-Cinnamon zeylanicum and pulp canal sealer EWT,Group IV- Plain pulp canal sealer EWT and compared. Results: It was found that all the groups exhibited varied antimicrobial activity against test microorganism. Highest antimicrobial efficacy was noticed in group III followed by group II, group I and least with group IV samples. Conclusion: Zinc oxide eugenol based sealer with plant extracts produced inhibitory zones against tested microorganism. Hence the plant extract can be added as one of the component of endodontic sealer, but further clinical trials need to be conducted before recommending them as sealers.

Wettability of endodontic sealers on the root surface using different irrigants

Objetivo: o presente estudo teve como objetivo avaliar a molhabilidade de diferentes cimentos em contato com a dentina tratada com irrigantes utilizados na remoção da smear layer, após o uso da clorexidina como substância auxiliar química. Material e Métodos: trinta dentes unirradiculares foram utilizados. As coroas foram removidas e as raízes seccionadas verticalmente, resultando em dois segmentos, que foram então achatados. Assim, foram obtidas 120 amostras medindo 5 mm. Eles foram imersos em gel de clorexidina 2% (CHX) por 10 minutos e lavados com água destilada (AD) antes de serem submetidos ao irrigante final para remoção da smear layer. Os seguintes protocolos de irrigação foram avaliados: grupo controle - CHX + AD + AD + AD; grupo E-CHX + AD + 17% EDTA + AD; grupo Q-CHX + AD + QMix + AD; grupo Et-CHX + DA + 18% HEBP + DA. As amostras foram secas e o ângulo de contato foi analisado por meio de um goniômetro. Os selantes avaliados foram: AH Plus (AH), Pulp Canal Sealer EWT (PCS) e MTA Fillapex (MTAF). Em cada gota de cimento, 60 medidas foram feitas e o fluxo foi observado por 1 minuto. A molhabilidade dinâmica dos selantes foi calculada. Os dados foram analisados ??estatisticamente. Resultados: em todos os cimentos, a presença de smear layer desfavoreceu a molhabilidade. EDTA e QMix favoreceram a molhabilidade de AH e PCS. Para o MTAF, o QMix apresentou o melhor desempenho, seguido pelo EDTA. A HEBP apresentou resultados estatisticamente inferiores, semelhantes ao controle. Conclusão: As soluções utilizadas para remoção da smear layer, após o uso de clorexidina durante o preparo, influenciaram a umectabilidade dos selantes AH Plus, Pulp Canal Sealer EWT e MTA Fillapex.

Cytotoxicity Profile of Endodontic Sealers Provided by 3D Cell Culture Experimental Model.

The aim of the present study was to evaluate the cytotoxic effects of five endodontic sealers (AH Plus, Endomethasone N, EndoSequence BC, MTA Fillapex and Pulp Canal Sealer EWT) using a three-dimensional (3D) cell culture model. A conventional bi-dimensional (2D) cell culture model was used as reference technique for comparison. Balb/c 3T3 fibroblasts were cultured in conventional bi-dimensional cell culture and in rat-tail collagen type I three-dimensional cell culture models. Then, both cell cultures were incubated with elutes of freshly mixed endodontic sealers for 24 h. Cell viability was measured by the methyl-thiazol-diphenyltetrazolium assay (MTT). Data were statistically analyzed using ANOVA and the Tukey test at a significance level of p<0.05. All tested sealers exhibited cytotoxic effects; however, cytotoxic effect was culture model- and sealer-dependent. Sealers showed higher cytotoxicity in 2D than in 3D cell culture model (p<0.05). In both conditions, EndoSequence BC showed the lowest cytotoxicity (p<0.05). MTA Fillapex was much more cytotoxic than the other tested endodontic sealers (p<0.05), with the exception of AH Plus in the 2D cell culture model (p>0.05). Endomethasone N and Pulp Canal Sealer EWT showed lower cytotoxic effects than AH Plus in 2D cell culture model (p<0.05); however no statistical differences was observed among these sealers in 3D cell culture model. It may be concluded that cytotoxicity was higher in 2D cell culture compared to 3D cell culture. EndoSequence BC sealer exhibited the highest cytocompatibility and MTA Fillapex the lowest cytocompatibility.

Efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl

Resumo Introdução O tratamento de plasma é uma tecnologia eficaz que pode manter as propriedades internas dos materiais inalteradas após o tratamento, modificando apenas a superfície. Objetivo Avaliar o efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl 6%. Material e método Foram utilizados 60 incisivos bovinos. A coroa foi removida, a raiz foi dividida e as faces planificadas, totalizando 120 segmentos referentes ao terço cervical. As amostras foram divididas em dois grupos: controle (imersa em NaOCl 6%, lavada com água destilada, seca, imersa em EDTA 17%, lavada e seca) e plasma de oxigênio (após tratamento descrito no grupo controle, plasma de oxigênio foi aplicado por 30 s). As amostras foram avaliadas qualitativamente em relação à topografia por microscopia eletrônica de varredura, utilizando-se microfotografias com ampliação de 1.000×. O goniômetro Ramé-hart foi utilizado para a mensuração do ângulo de contato entre as superfícies e as seguintes soluções foram utilizadas: água, etilenoglicol e di-iodometano. Em seguida, a energia de superfície, representada pelas componentes polar e dispersiva, foi calculada. Avaliou-se também o escoamento dos cimentos Pulp Canal Sealer EWT (PCS) e Real Sal SE (RS) na superfície dentinária. Os dados foram analisados estatisticamente utilizando os testes Kruskal-Wallis e Mann-Whitney U (p&lt;0,05). Resultado O tratamento com plasma levou à formação de uma camada semelhante à smear layer na superfície dentinária. Este tratamento levou a um aumento da energia de superfície e da componente polar, favorecendo a hidrofilicidade da superfície. Entretanto, desfavoreceu o escoamento do cimento PCS e não influenciou no escoamento do cimento RS. Conclusão O plasma de oxigênio ocasionou mudanças topográficas na superfície dentinária, favorecendo a hidrofilicidade desta. Contudo, não favoreceu o escoamento dos cimentos endodônticos na dentina.

Surface modification of gutta-percha cones by non-thermal plasma

This study was designed to evaluate the effects of Oxygen and Argon plasma on gutta-percha surfaces. A total of 185 flat smooth gutta-percha surfaces were used. Samples were divided into groups: control: no plasma treatment; Oxygen: treatment with Oxygen plasma for 1min; Argon: treatment with Argon plasma for 1min. Samples were evaluated topographically by scanning electron microscopy and atomic force microscopy; and chemically by Fourier Transform-infrared Spectroscopy. A goniometer was used to determine the surface free energy and the wettability of the endodontic sealers. Additionally 60 bovine teeth were filled using pellets of gutta-percha (control, oxygen and argon plasma) and the sealers. Teeth were evaluated by push-out and microleakage tests. Data were statistically analyzed using specific tests. Argon plasma did not change the surface topography, while Oxygen plasma led to changes. Both treatments chemically modified the gutta-percha surface. Argon and Oxygen plasma increased the surface free energy and favored the wettability of AH Plus and Pulp Canal Sealer EWT. Regarding bond strength analysis, for AH Plus sealer, both plasma treatments on gutta-percha favored the bond strength to dentin. However, for Pulp Canal Sealer, there is no statistically significant influence. For leakage test, dye penetration occurred between sealer and dentin in all groups. In conclusion, Oxygen plasma led to both topographic and chemical changes in the gutta-percha surface, while Argon plasma caused only chemical changes. Both treatments increased the surface free energy, favoring the wettability of AH Plus and Pulp Canal Sealer EWT sealers and influenced positively in the adhesion and leakage.

Filling Effectiveness and Dentinal Penetration of Endodontic Sealers: A Stereo and Confocal Laser Scanning Microscopy Study.

The aim of this study was to evaluate the filling effectiveness and dentinal penetration of the sealers AH Plus, Pulp Canal Sealer EWT, Sealapex and MTA Fillapex applied according to the vertical condensation technique using thermoplastic gutta-percha. Forty single-rooted teeth were selected. After chemical-mechanical preparation and root-canal filling, sections of the root (2, 4 and 6 mm from the apex) were obtained and analyzed by stereo microscopy and confocal laser scanning microscopy. Data were tabulated and statistically analyzed. With regard to the assessment of void spaces in the filling material at 2 mm from the apex, the sealers showed similar results, but at 4 and 6 mm from the apex, MTA Fillapex had inferior performance compared to AH Plus (at 4 mm), Pulp Canal Sealer EWT (at 4 and 6 mm) and Sealapex (at 6 mm) (p<0.05). With regard to the penetration into dentinal tubules at 2 mm from the apex, the sealers also showed similar results, but at 4 and 6 mm Pulp Canal Sealer EWT had an inferior performance compared to MTA Fillapex and AH Plus, respectively (p<0.05). All four sealers were found to be similar regarding adaptation of the filling material to the root canal walls, except the MTA Fillapex, which showed failures at 4 and 6 mm from the root apex. With regard to the ability to penetrate into the dentinal tubules, the sealers were found to be equivalent, except for the Pulp Canal Sealer EWT as it had poorer results at 4 and 6 mm compared to MTA Fillapex and AH Plus, respectively.

Response of Human Osteoblastic and Osteoclastic Cells to AH Plus and Pulp Canal Sealer Containing Quaternary Ammonium Polyethylenimine Nanoparticles

IntroductionThe incorporation of quaternary ammonium polyethylenimine (QPEI) nanoparticles into endodontic sealers induces alterations in their structure and surface properties, which may affect the compatibility with the periapical tissues. This work addressed the behavior of human bone cells exposed to extracts from commercial and QPEI containing AH Plus (DeTrey, Konstanz, Germany) and Pulp Canal Sealer EWT (PCS; Kerr Italia Srl, Salerno, Italy). MethodsFreshly mixed AH Plus and PCS or containing 2% QPEI (0.3 mL spread over the well bottom of a 24-well plate) were extracted with culture medium (1.5 mL for 24 hours at 37°C) and diluted (1:20–1:5000). Osteoblastic or osteoclastic cells were cultured in the presence of QPEI particles (1%–10%) and were exposed to the extracts from unmodified and QPEI containing sealers. ResultsQPEI nanoparticles, at 1% and 2%, did not affect cell behavior. On osteoblastic cells, AH Plus and PCS increased DNA at 1:2500 dilution (levels ≤1:100 were cytotoxic). Alkaline phosphatase activity decreased at dilutions ≤1:500. Comparatively, QPEI containing AH Plus increased DNA at 1:2500 and 1:500 dilutions, and QPEI containing PCS induced ALP activity at 1:2500 and 1:500 dilutions. Regarding osteoclastic cells, DNA increased (AH Plus) or was not affected (PCS) at dilutions up to 1:500 and decreased with more concentrated extracts. Tartrate-resistant acid phosphatase activity decreased with dilutions ≤1:500 for both sealers. QPEI containing sealers presented a similar behavior. The sealers affected some intracellular signaling pathways, and QPEI containing sealers further modulate these mechanisms. ConclusionsQPEI nanoparticles, at 2%, did not affect cell behavior. However, the incorporation of 2% QPEI particles into AH Plus and PCS modulates the proliferation and differentiation of bone cells, depending on the sealer and the cell type, without increasing the sealers' cytotoxicity.

Antibiofilm Effects of Endodontic Sealers Containing Quaternary Ammonium Polyethylenimine Nanoparticles

IntroductionThis study evaluated the antibiofilm effects of 2 endodontic sealers incorporated with quaternary ammonium polyethylenimine (QPEI) nanoparticles at a 2% concentration (w/w). MethodsThe materials tested were AH Plus and Pulp Canal Sealer EWT (PCS) in the commercial unmodified form or containing 2% QPEI. Antibiofilm assays were conducted by using direct-contact and membrane-restricted tests for evaluation of bacterial viability in biofilms grown onto membranes or paper disks and the crystal violet microtiter-plate assay to evaluate the effects of sealer extracts on the biofilm biomass. Two Enterococcus faecalis strains (ATCC and an endodontic isolate) were used. ResultsDirect contact and membrane-restricted antibiofilm tests revealed that PCS 2% was the only material to promote total killing of E. faecalis ATCC biofilms. All the materials significantly reduced bacterial counts in E. faecalis ATCC biofilms when compared with the positive control in both tests (P < .05). In the direct test against E. faecalis RW35, PCS 2% was significantly more effective than the other materials and was the only one that showed significantly lower counts than the positive control (P < .05). In the crystal violet assay, only AH Plus 2% presented optical density readings significantly lower than the positive control of the ATCC strain (P < .05). No other significant effects on the biofilm biomass of the 2 E. faecalis strains were observed for any of the sealers tested (P > .05). ConclusionsAddition of QPEI nanoparticles improved the killing ability of PCS against biofilms of both E. faecalis strains and the effects of AH Plus on the biomass of biofilms from the ATCC strain.

Dentin Extends the Antibacterial Effect of Endodontic Sealers against Enterococcus faecalis Biofilms

IntroductionThe purpose of this study was to evaluate the antimicrobial effects of root canal sealers on Enterococcus faecalis biofilms in dentinal tubules by using a novel dentin infection model. MethodsCells of E. faecalis were introduced into the dentinal tubules by centrifugation and incubated in brain-heart infusion broth for 3 weeks. An equal thickness of AH Plus, Endosequence BC sealer (BC sealer), and pulp canal sealer EWT (PCEWT) was placed on the root canal wall of the dentin specimens for 1, 7, and 30 days in humid conditions at 37°C. Gutta-percha and water were used in a similar manner as the tested sealers. The proportions of dead and live bacteria inside the dentinal tubules after exposure to root canal sealers were assessed by confocal laser scanning microscopy. ResultsSignificantly more bacteria were killed in the 3 sealer groups than in the 2 control groups (P < .05). BC sealer and AH Plus resulted in significantly more dead cells than PCEWT did. There was no statistically significant difference between BC sealer and AH Plus at any time point (P > .05). Thirty days of exposure to BC sealer and AH Plus resulted in significantly more dead bacteria in dentin than 7-day and 1-day exposures in the biofilms, whereas no statistically significant increase of the proportion of dead bacteria was detected between 7-day and 30-day PCEWT (P > .05). ConclusionsThe 3 endodontic root canal sealers had antibacterial effects against E. faecalis in the dentinal tubules. BC sealer and AH Plus had superior antibacterial effects compared with PCEWT. The antibacterial effects of sealers in dentinal tubules continued after setting.

Antibacterial, physicochemical and mechanical properties of endodontic sealers containing quaternary ammonium polyethylenimine nanoparticles

To evaluate the antibacterial, physicochemical and mechanical properties of two endodontic sealers incorporating quaternary ammonium polyethylenimine (QPEI) nanoparticles at concentrations of 1% and 2% (w/w). The sealers tested were AH Plus and Pulp Canal Sealer EWT in the commercial unmodified form or containing 1% or 2% QPEI. Antibacterial activity was evaluated using a direct contact test (DCT) against Enterococcus faecalis ATCC 29212 and two endodontic isolates (RW35 and RN44). Sealers freshly mixed or set for 7days were exposed to bacterial suspensions for 10, 30 and 60min. Setting time, flow test, solubility, apparent porosity, dimensional change following setting, wettability, zeta potential and compressive strength were assessed according to the International Standard Organization 6876:2001 (ISO 6876). DCT results revealed that both freshly prepared sealers had antibacterial effects unaffected by QPEI incorporation. Both unmodified sealers had lost much of their antibacterial effects after 7days. However, for Pulp Canal Sealer EWT incorporated with 1% and 2% QPEI nanoparticles, the antibacterial effects against all test E.faecalis strains within 30 and 60min of contact were significantly greater than the unmodified formula. Addition of QPEI resulted in no significant increase in the antibacterial effects of AH Plus after ageing. As for physicochemical and mechanical tests, setting time, wettability and zeta potential were influenced by the presence of QPEI nanoparticles. Incorporation of QPEI nanoparticles can improve the long-term antibacterial activity of Pulp Canal Sealer EWT without relevant changes in physicochemical and mechanical properties.

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, 1x105 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.

Fluid filtration and dye leakage testing of Resilon/Epiphany and guttapercha/Pulp Canal Sealer root canal fillings

The aim of the present study was to compare sealing abilities of Resilon/Epiphany (R/E) with those of guttapercha and Kerr Pulp Canal Sealer EWT (GP/PCS). 50 single rooted teeth were randomly divided into 2 groups (n = 22) (R/E; GP/PCS), and 2 control groups (n = 3) (Positive, Negative). Fluid flow rate through the filled roots was measured using a fluid filtration device. The same specimens were immersed in a 2% Methylen Blue Solution. Roots were embedded in clear epoxy resin and cross sectionet at 1 mm intervals along the length of the root. Circumferential dye penetration was evaluated at 40× magnification. Fluid filtration of teeth obturated with the R/E system (0.085 [0.057, 0.113] μL·min-1), and dye penetration test showed no statistically significant difference compared to those obturated with GP/PCS (0.113 [0.057, 0.141] μL·min-1). Within the limits of the present study, there is no statistically significant difference between R/E and GP/PCS sealing abilities.

The effect of immediate and delayed post-space preparation using extended working time root canal sealers on apical leakage

Background/purposeThe purpose of this study was to compare the effect of different post-space preparation time intervals on the apical sealing ability of filling material using two different extended setting time root canal sealers. Materials and methodsA total of 100 single-canal teeth were incrementally cleaned with crown-down instrumentation using K3 rotary nickel–titanium instruments and randomly divided into four groups. There were 30 teeth in the experimental groups (Groups 1–3) and 10 teeth in the control group (Group 4). We obturated the teeth using a warm gutta-percha vertical compaction technique with pulp canal sealer (Group 1), Tubli-Seal EWT (Group 2), and pulp canal sealer EWT (Group 3). We then stored all the specimens in 100% humidity at 37°C for 1 week. We used heated pluggers to create post space at three different intervals postobturation (i.e., immediately after obturation, on Day 3, and on Day 7), leaving 5-mm gutta-percha filling at the apices. We then immersed the teeth in 2% methylene blue solution for 72 hours, and finally sectioned them longitudinally into two halves. The amount of apical dye leakage was measured under a stereomicroscope. ResultsThe results showed no significant difference (P > 0.05) in dye leakage between the standard and extended working time root canal sealers. Apical leakage tended to increase more severely in Group 1 at the three different intervals was considered. ConclusionExtended working time root canal sealers do not affect microleakage results using a warm gutta-percha vertical compaction technique. The sealing ability of extended working time root canal sealers on high heat conditions is as good as the standard working time root canal sealer during post-space preparation of different intervals.

Effects of calcium phosphate endodontic sealers on the behavior of human periodontal ligament fibroblasts and MG63 osteoblast‐like cells

In regard to biological properties of endodontic sealers, there are many characteristics that should be considered. The aim of this study was to examine the biological effects of new calcium phosphate-based root canal sealers, CAPSEAL I and CAPSEAL II (CPS), on human periodontal fibroblast cells by examining the expression levels of inflammatory mediators and to compare the effects of CPS on the viability and osteogenic potential of human osteoblast MG63 cells compared to those of other commercially available calcium phosphate sealers [Apatite Root Sealer type I (ARS I) and Apatite Root Sealer III (ARS III); Sankin Kogyo, Tokyo, Japan] and a zinc oxide eugenol-based sealer (Pulp Canal Sealer EWT [PCS EWT]; Kerr, Detroit, MI). The levels of IL-6 in the new CPS group (CAPSEAL I, II) were higher than those in the control and all experimental groups at all time points after 2 h. TGF-β1 and FGF-1 levels decreased at 72 h compared to the levels in the control, in cells treated with every sealers except ARS I. The new CPS sealers showed low cytotoxicity. Reverse transcription polymerase chain reaction showed that CAPSEAL I, II, and Apatite Root Sealer type III induced expression of early stage markers of differentiation (alkaline phosphatase and osteopontin) at 7 days. Also, new CPS showed higher mineralized nodule formation at 28 days. These results suggest that CAPSEAL I and II facilitate the periapical dentoalveolar and alveolar healing by controlling cellular mediators from PDL cells and osteoblast differentiation of precursor cells.

Evaluation of the cytotoxicity of different root canal sealers on L929 cell line by MTT assay

The purpose of this study was to evaluate the cytotoxic effects of commercially available root canal sealers [Sealite Ultra (SU), Tubli-Seal (TS), Tubli-Seal EWT (TS-EWT), Pulp Canal Sealer (PCS), Pulp Canal Sealer EWT (PCS-EWT), Endomethasone N (En N), and Apexit Plus (AP)] on L929 cells by using MTT assay. After incubation with each sealer's extract at 37°C in a humidified air atmosphere containing 5% CO(2 )for 24 h, MTT (5 mg/mL) in saline was added into each well and further incubated at 37°C for 4 h. Formazan precipitate was dissolved in a buffer containing 23% sodium dodecyl sulfate and 50% N, N-dimethylformamide (pH 4.7). Optical densities of dissolved formazan were read using a microplate spectrophotometer. AP, TS, and TS-EWT showed no cytotoxicity at any dilution tested. Other sealers exhibited some degree of cytotoxicity at the 1/4 and 1/2 dilutions. PCS-EWT and SU exerted more potent cytotoxicity at 1/2 dilution than the other sealers.

Evaluation of cytotoxicity and up‐regulation of gelatinases in human fibroblast cells by four root canal sealers

To investigate the effects of root canal sealers on the cytotoxicity and gelatinolytic activity of matrix metalloproteinases (MMPs) in human fibroblasts. Human fibroblasts (MRC5, 3×10(5) cells per well) were incubated directly or indirectly with AH Plus, Endomethasone N, Pulp Canal Sealer EWT or Sealapex for 30 min, 1, 4 or 24 h (time-points). The cytotoxicity of all root canal sealers was determined by counting viable cells using the trypan blue exclusion assay. Supernatants of cell cultures incubated with root sealers directly or indirectly were collected after each time-point to determine the levels of MMP-2 and MMP-9 gelatinolytic activity by gelatin zymography. Data were analysed using anova and the Tukey's tests. Cells secreted MMP-2 after periods of 4 and 24 h; however, there were no significant differences between the sealers. Secretion of gelatinases was elevated by root canal sealers in direct contact with the cell monolayer when compared to indirect contact (P < 0.05). At the time-points tested, no gelatinolytic activity could be detected in the control group without the sealers. The cytotoxicity results revealed that all sealers were cytotoxic in both contact forms. Sealapex had the lowest cytotoxicity and AH Plus the most cytotoxicity. All root canal sealers induced the expression of MMP-2 in MRC5 fibroblasts. AH Plus had the highest cytotoxicity amongst the tested sealers, but all were associated with cytotoxic effects.

A multiparametric assay to compare the cytotoxicity of endodontic sealers with primary human osteoblasts

To compare the cytotoxicity of four endodontic sealers (Sealapex, Pulp Canal Sealer EWT, Real Seal and MTA Fillapex) either 1 or 7 days after mixing, when assessed through a multiparametric analysis employing human primary cells closely related to periapical tissues. Extracts of each sealer were prepared following 24-h exposure to culture media, at either 24 h or 7 days after mixing. Primary human osteoblasts were exposed to extracts for 24 h, at 37 °C with 5% CO(2) , 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 and experimental time were compared by 2-way analysis of variance (anova). All endodontic sealers had strong cytotoxicity 24 h after mixing, according to all parameters evaluated. At a longer setting period (7 days), viability for Sealapex was significantly increased (P < 0.05) and Pulp Canal Sealer achieved levels of cytocompatibility similar to the control group. The anova indicated a general correlation between the cytotoxicity of the materials and the time after mixing, with some level of dependence on the cell viability assay employed. All materials had high cytotoxic levels for human primary cells, mostly on a time-dependent basis, as shown by three different cell viability tests.