RealSeal SE Research Articles

Comparative Evaluation of the Apical Sealability of AH Plus and RealSeal SE Using 5.25% Sodium Hypochlorite with 17% EDTA and 10% Citric Acid as Irrigants-An In Vitro Study.

Apical microleakage is considered to be a common reason for the clinical failure of endodontic therapy. Three dimensional sealing of the root canal is one of the main goals of endodontic treatment and is essential for preventing reinfection of the canal and for preserving the health of the periapical tissues, Recently Epoxy resin sealers have been used because of their reduced solubility apical seal and micro-retention to root dentine. This in vitro study was done to evaluate and compare the apical sealability of AH Plus and RealSeal SE using 5.25% sodium hypochlorite with 17% EDTA and 10% citric acid as irrigants. Materials and methods: 44 single-rooted premolars were selected and the teeth are randomly divided into 4 groups (n=10) and 2 control groups (n=2). The extent of dye penetration, from the apical to the coronal part of the root canal, was assessed using a stereomicroscope at 10x magnification for all groups.One-way ANOVA and Kruskal-Wallis tests were performed to compare statistically significant differences among the groups, using SPSS software version 10.0. Group IV (Citric acid + RealSeal SE) showed a statistically lower mean microleakage when compared to all other groups. From, the present study, it was concluded that, RealSeal SE sealer with 10% citric acid as irrigant (group IV) showed better apical sealability followed by RealSeal SE sealer with 17% EDTA as irrigant (group III), when compared to AH Plus groups which showed least sealability.

On the biocompatibility of endodontic sealers.

Periapical tissue may be exposed to root canal filling materials in consequence of root canal therapy. There is scant scientific data about the biocompatibility of root canal filling materials of various chemistry on the periapical area. This study aimed to investigate the effects of different root canal sealers and their eluates on human alveolar osteoblasts in terms of cell proliferation, adhesion, morphology and gene expression in vitro. Five endodontic sealers (AH Plus®, Apexit®, Tubli-Seal®, Real Seal SE®, EndoRez®) and one gutta-percha obturation material (BeeFill®) were tested. Human alveolar osteoblasts derived from 3 different donors following incubation with sealer eluates after 24 h and 72 h were investigated by means of qPCR (gene expression). Morphological reactions of the alveolar osteoblasts were measured by culturing the cells for 3 d, and 7 d and 14 d, respectively, followed by scanning electron microscopy (morphology, adhesion) and fluorescence imaging of the actin cytoskeleton (morphology, proliferation). A repeated measures analysis was performed and p-values were adjusted by Tukey. While all sealers influenced the cell morphology and the expression of genes associated with apoptosis (Casp3), proliferation (histone H3), and inflammation (interleukin-6 and matrix metalloproteinases 1 and 3), mainly AH Plus® and Apexit® yielded a regular actin cytoskeleton and beneficial gene expression patterns. Regarding cell adhesion, only AH Plus® supported proper anchorage for alveolar osteoblasts. Our results provide evidence for the biocompatibility of epoxy resin-based endodontic sealers, i.e. AH Plus®, while other sealers proved cytotoxic for alveolar osteoblasts. Further studies are needed for understanding the bone cell reactions after endodontic treatment and the clinical decision-making regarding the sealer of choice for root canal fillings.

Evaluation of Bond Strength of Four Different Root Canal Sealers.

The purposes of the study were to evaluate the influence of the sealer’s chemical composition on the interfacial strength between root canal dentin and root filling material, for two different classes of endodontic sealers, and to assess their failure modes. Methods: Forty extracted single-rooted teeth were randomly divided into four groups using the following endodontic sealers: RealSeal SE and Resilon (RSSE); EndoSequence BC sealer and BC Point (EBCS); Endoseal MTA and gutta-percha (EDS); Bioroot RCS and gutta-percha (BRS). Teeth were embedded in acrylic resin, and the roots were sectioned horizontally into 1 mm slices. For each slice, the perimeter was measured. A push-out test was performed using an Instron universal testing machine. For each sample, bond strength was calculated. Specimens were examined by SEM investigation in order to analyze the dentin–sealer–core interface. Results were assessed using analysis of variance (ANOVA) and Tukey and Bonferroni test. Results: Statistical analysis revealed that EDS and gutta-percha had significantly higher resistance to dislodgement compared to the other three groups (p < 0.05). EBCS and BC Point showed significantly greater push-out bond strength values compared to RSSE and Resilon (p < 0.05). Conclusions: Bioceramic endodontic sealers showed a higher bond strength to root dentin than methacrylate resin-based endodontic sealer.

Fracture Resistance of Roots Obturated with Resilon and EndoREZ with Self-Adhesive Root Canal Sealers

&lt;sec&gt; &lt;title&gt;Objective:&lt;/title&gt; This laboratory study aimed to evaluate the effect of self-adhesive root canal sealers on the fracture strength of root canals filled with Resilon or EndoREZ. &lt;/sec&gt; &lt;sec&gt; &lt;title&gt;Materials and Methods:&lt;/title&gt; A total of eighty extracted mandibular premolar teeth were selected in this in-vitro study. All teeth were instrumented using a crown-down technique by FlexMaster rotary NiTi files. Specimens were divided into 4 test groups (n = 20) according to the sealer material: RS; RealSeal, RSS; RealSeal SE, MS; MetaSeal, and CG; (control group) zinc oxide eugenol-based sealer. Each main group was distributed into two subgroups (n = 10) according to the filling material either Resilon or EndoREZ and gutta-percha (n = 20) in the control group. Each root was mounted in acrylic resin blocks and subjected to fracture in a universal testing machine. The load values at root specimens fractured were registered in Newton’s and the data were analyzed using two-way analysis of variance and the Tukey HSD test (α = 0.05). &lt;/sec&gt; &lt;sec&gt; &lt;title&gt;Results:&lt;/title&gt; The two-way analysis of variance analysis indicated that the filling material had a significant effect on the fracture strength of endodontically treated teeth (p &lt; 0.05) but not the sealer materials (p≥.05). Higher mean fracture strength was recorded in MetaSeal and Resilon group (1281.90±200.34 N) and lower mean fracture strength was shown in RealSeal and EndoREZ group (847.55±191.04 N). &lt;/sec&gt; &lt;sec&gt; &lt;title&gt;Conclusion:&lt;/title&gt; Self-adhesive (fourth-generation) resin sealers increased the fracture strength of root teeth more than self-etching (third-generation) root canal sealers when used with EndoREZ points. &lt;/sec&gt;

Effect of two irrigation protocols and obturation techniques on the apical sealing ability of different root canal sealers: An in vitro study

Abstract Aim: The aim of this study was to compare the influence of two irrigation protocols and obturation techniques on the apical seal of three endodontic sealers. Materials and Methods: Crowns of 130 single-rooted teeth were cut and 10 roots were selected as controls, and the remaining roots were divided into four experimental groups (n = 30) according to the type of irrigation protocol and obturation technique. Each group was divided into three subgroups (n = 10) according to the type of root canal sealer. All root canals were prepared with size F4 Protaper Universal and irrigated with 3% sodium hypochlorite (NaOCl) + 3% hydrogen peroxide (H2O2) (Groups 1 and 3) or 3% NaOCl + 2% chlorhexidine (CHX) (Groups 2 and 4). Two gutta-percha obturation techniques were used: single-cone (Groups 1 and 2) and continuous wave (Groups 3 and 4) techniques. The following sealers were tested: MTA Fillapex (Subgroup A), AH Plus (Subgroup B), and Realseal SE (Subgroup C). The apical seal was assessed using dye penetration method, and the data were statistically analyzed. Results: In the first group, AH Plus showed the best apical seal (0.46 ± 0.098 mm), while RealSeal SE system showed the worst apical seal (3.47 ± 0.434 mm). In the second group, MTA Fillapex (0.58 ± 0.115 mm) and AH Plus (0.63 ± 0.109 mm) showed the best apical seal. In the third and fourth groups, all types of sealers showed similar high leakage patterns. Marked increase in the apical seal of RealSeal was observed in the third group (1.71 ± 0.453 mm). Conclusions: The type of irrigation protocol and obturation technique could affect the apical seal of tested sealers. When the single-cone technique was used, AH Plus with NaOCl + H2O2 and MTA Fillapex with NaOCl + CHX irrigation protocols showed significantly a high apical seal. RealSeal SE showed the worst apical seal when canals were irrigated with NaOCl/H2O2 and filled with the single-cone technique. All sealers showed inferior results when used with the continuous wave technique.

Comparison of warm vertical compaction and cold lateral condensation of α, β gutta-percha and resilon on apically extruded debris during retreatment

This study was performed to evaluate the amount of apically extruded debris removed from a root canal filled with cold lateral condensation (CLC), and warm vertical compaction (WVC) techniques, using b or a phase gutta-percha with AH-Plus (Dentsply DeTrey, Konstanz, Germany) or Resilon (Resilon Research LLC, Madison, WI) with RealSeal SE (SybronEndo, Amersfoort, The Netherlands). About 100 human incisor teeth were prepared with a #25.06 NiTi rotary system and divided into five groups according to the filling material used: Group 1: CLC (gutta-percha, AH-Plus); Group 2: WVC (b phase gutta-percha, AH-Plus); Group 3: WVC (a phase gutta-percha, AH-Plus); Group 4: CLC (Resilon, RealSeal SE); and Group 5: WVC (Resilon, RealSeal SE). Extruded debris during the retreatment procedure was collected in preweighed Eppendorf tubes. The times required for retreatment were recorded. The amount of debris extrusion was significantly greater with WVC than CLC in the gutta-percha and Resilon groups (P < 0.001). Using a phase gutta-percha resulted in significantly more debris extrusion than b phase gutta-percha (P < 0.001). In the WVC groups, Resilon caused significantly more debris extrusion than gutta-percha (P < 0.05). Retreatment was faster for CLC than WVC (P < 0.05). In the retreatment procedure, the amount of apically extruded debris and retreatment duration were dependent on the type of obturation material and technique used.

Effect of Different Irrigation Solutions on the Apical Sealing Ability of Different Single-cone Obturation Systems: An In Vitro Study

The aim of this study was to assess the effect of three root canal irrigants on the apical sealing ability of three single-cone obturation systems. One hundred maxillary central incisors were selected and their crowns were cut. The roots were divided into three experimental groups of 30 samples each, and one control group of 10 samples (5 positives and 5 negatives). Each experimental group was divided equally into three subgroups according to the obturation system. All root canals were instrumented using ProTaper Universal rotary system and irrigated with 3% sodium hypochlorite (Group 1), 2% chlorohexidine (Group 2), 3% hydrogen peroxide (Group 3). Finally, root canals were irrigated with 17% EDTA followed by distilled water, then obturated with a single-cone technique using gutta-percha/MTA Fillapex (Subgroup A), gutta-percha/ AH Plus (Subgroup B), and Resilon/Relseal SE (Subgroup C). The microleakage was assessed using linear dye penetration method and data were statistically analyzed. Significant differences were found between all groups and subgroups (p < 0.005). When 3% of hydrogen peroxide was used, no leakage was observed with AH Plus sealer, and a high amount of leakage (5.82 ± 0.47 mm) was observed with Realseal SE. MTA Fillapex (0.49 ± 0.08 mm) and Realseal SE (1.11 ± 0.50 mm) showed the lowest amounts of leakage when 2% chlorohexidine and 3% sodium hypochlorite were used, respectively. The type of irrigating solution and obturation system could affect the apical leakage value when single-cone obturation technique was used. AH Plus/gutta-percha obturation system showed no apical leakage when root canals were irrigated with 3% hydrogen peroxide. The using of 2% chlorohexidine improved sealing ability of MTA Fillapex/gutta-percha. The apical sealing ability of Realseal SE/Resilon decreased when 3% hydrogen peroxide or 2% chlorhexidine was used. Proper selection of irrigating solutions may positively influence the apical sealing ability of single-cone obturation systems.

Efficacy of several rotary systems in removal of two different obturation materials during endodontic retreatment

Background/Aim. In order to achieve good results in endodontic retreatment, satisfactory removal of filling material and adequate debridement of the root canal is necessary. The aim of this in vitro study was to evaluate the efficacy of three rotary systems in removing gutta-percha/AH Plus and RealSeal SE obturation materials during retreatment using scanning electron microscopy. Methods. A total of 72 freshly extracted mandibular first incisors were enlarged to a size #30 using iRaCe NiTi instruments. Teeth were randomly divided into 6 groups of 12 specimens each. 36 teeth (groups 1, 2 and 3) were filled with AH Plus?/gutta-percha and another 36 (groups 4, 5 and 6) with Resilon (RealSeal SE system), both using lateral condensation technique. In groups 1 and 4, the retreatment was performed using the ProFile System, in groups 2 and 5 using the ProTaper Universal Retreatment System and in groups 3 and 6 using the D-RaCe system. After retreatment the teeth were split vertically into halves and efficacy of retreatment techniques was evaluated by scanning electron microscopy. The assessment and comparisons of 3 parameters: smear layer, filling debris and surface profile irregularities were made using a predefined scale. These 3 parameters were evaluated in the coronal, middle and apical thirds of the root. Statistical analysis was performed using the Kruskal-Wallis test with the Bonferroni post-hoc test. Results. In the AH Plus/gutta-percha samples filling debris removal was significantly better when the D-RaCe and ProTaper System were used compared to the ProFile in the apical third. Less dentin irregularities were observed when the ProTaper was used compared to the ProFile system (p = 0.0139). In the RealSeal samples, no significant differences were found between the retreatment methods. Conclusion. None of the instrumentation technique completely removed filling material from the root canal, which implies the need for more research in this field. The apical third of the root canal was the most complicated area in terms of complete smear layer and filling debris removal and presence of surface profile irregularities regardless the filling materials.

The effect of chlorhexidine and dimethyl sulfoxide on long-term microleakage of two different sealers in root canals

Objective:The aim of root canal obturation is to prevent leakage and inhibit microbial invasion. This study aimed to determine the effect of chlorhexidine (CHX) and dimethyl sulfoxide (DMSO) as final irrigants on microleakage of root filling immediately and after 18 months. The hypothesis was that either CHX or DMSO would not affect the immediate or long-term microleakage.Methods:A total of 120 human third molar root canals were obturated with RealSeal SE or Topseal and gutta percha. Before obturation, the canals were irrigated with saline (control), 2% CHX or 5% DMSO. Microleakage of half of each groups (n=10) was measured after 3 days, and of the other half was measured after 18 months with fluid filtration method.Results:In immediate measurements, RealSeal SE performed significantly better in CHX-irrigated group (p=0.035; Mann-Whitney test). For both sealers, DMSO had the lowest mean microleakage values, which were also statistically significantly lower than with CHX irrigation within sealers (p<0.009 for Topseal and p=0.04 for RealSeal SE; Mann-Whitney test). With RealSeal SE, the microleakage with CHX was significantly higher than that in controls (p=0.022; Mann-Whitney test).Conclusion:Neither final irrigant showed statistically significant differences in the immediate microleakage within the two sealers. Irrigation with DMSO caused significantly less microleakage than CHX for both sealers after 18 months.

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.

Evaluation of apically extruded debris during removal of gutta-percha and ResilonTM using different instrumentation techniques

Background/Aim. Apical extrusion of material is considered as one of the very important factor for endodontic treatment success. Microorganisms, necrotic tissue, filling material and irrigants, which can be extruded apically during endodontic retreatment, may jeopardize the success of the therapy. The aim of this in vitro study was to quantitatively evaluate the amount of apically extruded debris during endodontic retreatment of teeth obturated with two different materials, using one hand and three rotary instrumentation techniques. Methods. Ninety-six extracted single-rooted teeth were endodontically treated and enlarged to size 40 using BioRaCe system, and then randomly divided into 8 groups of 12 specimens each. Half of the specimens were obturated with gutta-percha and AH Plus? sealer and another half with RealSeal SE system, using lateral condensation technique. Retreatment was performed using: Hedstr?m files; ProFile rotary files; ProTaper Retreatment system and D-RaCe system. Apically extruded debris was collected in pre-weighed Eppendorf tubes and evaluated using an electronic microbalance. Data were analyzed statistically using t-test and analysis of variance. Results. In the AH Plus/gutta-percha group, all tested rotary instruments gave significantly less extruded debris compared with Hedstr?m files (p &lt; 0.05). In theRealSeal group, there was significant difference between DRaCe and Hedstr?m instruments (p &lt; 0.05). Conclusion. All retreatment techniques resulted in apical extrusion. DRaCe system produced significantly less extruded debris compared to hand files. No significant difference was found when comparing two instruments specially designed for retreatment: D-RaCe and ProTaper systems.

The Tubular Penetration Depth and Adaption of Four Sealers: A Scanning Electron Microscopic Study.

Background. The tubular penetration and adaptation of the sealer are important factors for successful root canal filling. The aim of this study was to evaluate the tubular penetration depth of four different sealers in the coronal, middle, and apical third of root canals as well as the adaptation of these sealers to root canal walls. Materials and Methods. 50 single-rooted teeth were prepared in this study. Forty-eight of them were filled with different sealers (Cortisomol, iRoot SP, AH-Plus, and RealSeal SE) and respective core filling materials. Then the specimens were sectioned and scanning electron microscopy was employed to assess the tubular penetration and adaptation of the sealers. Results. Our results demonstrated that the maximum penetration was exhibited by RealSeal SE, followed by AH-Plus, iRoot SP, and Cortisomol. As regards the adaptation property to root canal walls, AH-Plus has best adaptation capacity followed by iRoot SP, RealSeal SE, and Cortisomol. Conclusion. The tubular penetration and adaptation vary with the different sealers investigated. RealSeal SE showed the most optimal tubular penetration, whereas AH-Plus presented the best adaptation to the root canal walls.

The effect of three different antioxidants on the dentinal tubular penetration of Resilon and Real Seal SE on sodium hypochlorite-treated root canal dentin: An in vitro study.

Objective:The effect of 10% ascorbic acid, 10% tannic acid, and 10% gallic acid on the dentinal tubular penetration of Resilon and Real Seal SE on sodium hypochlorite-treated root canal dentin was evaluated.Materials and Methods:Fifty human premolars were decoronated to attain 14-mm root length and divided into five groups of 10 teeth each. Biomechanical preparation was done with rotary instruments. Group I specimens were irrigated with saline and 17% ethylenediaminetetraacetic acid (EDTA). Specimens from groups II, III, IV, and V were irrigated with 5.25% sodium hypochlorite and 17% EDTA. Specimens from groups III, IV, and V underwent additional irrigation with antioxidants–10% ascorbic acid, 10% tannic acid, and 10% gallic acid, respectively. Following obturation with Resilon and Real Seal SE, scanning electron microscope (SEM) analysis was done to note the maximum dentinal tubular penetration at the cervical, middle, and apical thirds of each specimen. The data were statistically analyzed using one-way analysis of variance (ANOVA), Post hoc and Dunnett's test.Results:Maximum dentinal tubular penetration of Resilon and Real Seal SE was obtained following irrigation with 10% gallic acid.Conclusion:10% gallic acid was superior among the antioxidant irrigants that enabled the increased dentinal tubular penetration of Resilon and Real Seal SE.

Degree of conversion of a self-adhesive endodontic sealer when used as bulk material.

This study tested the null hypothesis that the opacity of RealSeal SE (RSSE) sealer makes light-curing inefficient, while the degree of conversion (DC) is similar regardless of curing method. Fourteen uniradicular teeth were sectioned at 15 mm from the apex. Root canals were instrumented using the Reciproc file system, bulk-filled with RSSE, and divided randomly into two groups (dual-cure or self-cure). DC was determined by micro-Raman spectroscopy at 24 h, 48 h, and 1 week after filling, at 6, 9, and 12 mm from the coronal end. Contrast ratio (Yb/Yw) was used to determine the opacity of the material. Descriptive statistics and nonparametric tests were used, and significance was defined as a P value of less than 0.05. Opacity was almost total by the first section, at 6 mm. In dual-cure mode, DC values at 24 h were lower in the apical section (63.8%) than in the more coronal sections and were lower than in self-cured specimens (87.4%). Light-curing of the coronal end did not improve DC. These differences remained at 48 h and 1 week. Only a small (2%) but significant increase in DC was observed in evaluations at 24 h and 1 week. (J Oral Sci 58, 333-338, 2016).

DNA double-strand breaks caused by new and contemporary endodontic sealers.

To investigate the cytotoxicity and genotoxicity of a new silicate-based BioRoot RCS® sealer in comparison with contemporary sealers. A periodontal ligament cell line using lentiviral gene transfer of human telomerase reverse transcriptase (hTERT) was used and exposed to subtoxic concentrations of 24-h eluates from two epoxy resin-based (AH Plus Jet® and Acroseal® ), four various methacrylate-based endodontic sealers (EndoREZ® , RealSeal® , RealSeal SE® and Hybrid Root SEAL® ) and three silicate-based sealers (BioRoot RCS® , iRootSP® and MTA Fillapex® ). The XTT-based cell viability assay was used for cytotoxicity screening of materials. The γ-H2AX assay was used for genotoxicity screening. In the γ-H2AX immunofluorescence assay, PDL-hTERT cells were exposed to eluates of the substances for 6h and DNA double-strand breaks (DSB) were detected microscopically. Induced foci represented DSBs, which can induce ATM-dependent phosphorylation of the histone H2AX. The statistical significance of the differences between the experimental groups was compared using the Student's t-test (P<0.05). The cytotoxicity of the 24-h eluates could be ranked in the following order: Hybrid Root SEAL® >RealSeal® >Acroseal® >RealSeal SE® ≥ AH Plus Jet® > EndoREZ® >MTA Fillapex® > iRoot SP® >BioRoot RCS® . In negative controls (cells which received medium only) 4.08±0.53 DSB foci (mean±SEM) whilst in positive controls 10.76±4.05DSB foci/cell were found. BioRoot RCS® and RealSeal SE® exhibited significant differences in foci formation at 1/3 EC50 compared with their 1/10 EC50 concentration (P<0.05). Both concentrations (1/10 and 1/3 of EC50) of AH Plus Jet® , Acroseal® , RealSeal® and MTA Fillapex® sealers were not significantly different when compared with the medium control (P<0.05). New BioRoot RCS® was not toxic whilst Hybrid Root SEAL® demonstrated more toxicity and DNA double-strand breaks when compared with other resin- and silicate-based root canal sealers.

STUDIUL INFILTRAŢIEI APICALE A OBTURAŢIILOR DE CANAL CU GUTAPERCĂ VERSUS RESILON

The purpose of the study is to assess the apical sealing ability of the endodontic space using two types of canal filling techniques: vertical compaction of warm gutta-percha and AhPlus sealer compared with Resilon and RealSeal SE. Two sets of extracted human teeth were prepared with rotary instruments, each 20 teeth being obturated by the two techniques: the classical and the adhesive root canal filling. The apical leakage of the root canal filling made with Resilon and RealSeal SE was higher than the one with gutta-percha and AhPlus. The difference was statistically significant.

Quantitative microleakage analysis of root canal filling materials in single-rooted canals.

The purpose of this study was to analyze the sealing ability of different root canal filling materials over a 6-week period using a glucose penetration model. Forty-six recently extracted human premolars were used in this study. The root canals were enlarged to 40/0.06. Prepared canals were randomly assigned into four groups (n = 10) as follows: Group 1, Gutta-Percha (GP)/AH Plus with cold lateral compaction; Group 2, GP/AH Plus with continuous wave compaction; Group 3, RealSeal SE obturation system; and Group 4, OrthoMTA. The remaining specimens were used as positive and negative controls, and all specimens underwent thermocycling (10,000; 5-55 °C). The sealing ability of all samples was evaluated at 24 h, 1, 2, 4, and 6 weeks using a quantitative glucose leakage model, and scanning electron microscope (SEM) images were taken. A mixed effect analysis using R statistical language was performed. Groups 1, 2, and 4 showed low leakage levels during experimental periods. Group 3 showed low leakage levels for the first 2 weeks; however, the leakage level was significantly increased after 2 weeks compared to negative control group (p < 0.05). In the SEM results, Group 3 showed imperfect dentin bonding, whereas Group 4 showed calcium silicate hydrate short tags, which are formed at the access of the dentin tubules. GP/AH Plus and OrthoMTA showed less microleakage than RealSeal SE obturation system when used as root canal filling materials. Traditional GP/AH Plus sealer and the newly developed OrthoMTA are more appropriate for ideal sealing of the root canals.

Solubility evaluation of different root canal sealing materials.

To evaluate the solubility of five different root canal sealers (AH Plus Jet, RealSeal SE, MTA Fillapex, Tubli-Seal, and Acroseal) in chloroform, eucalyptol and Endosolv-E solvents. Ninety root canal sealer samples were prepared and then divided into three groups for immersion in a solvent for 2, 5 or 10 minutes. The mean values of the root canal sealers' dissolution in the solvents were obtained by the difference between the preimmersion original weight and the post-immersion weight on a digital analytical scale. Data were statistically analyzed by a Kruskal-Wallis test with a Bonferroni correction. Chloroform was a more effective solvent than eucaly-ptol or Endosolv E for all root canal sealers, except for RealSeal SE, at all time points (p < 0.003). RealSeal SE was the least soluble sealer in all solvents at all time points. Chloroform demonstrated a superior ability over other solvents in dissolving canal sealing materials, and eucaly-ptol was found to be the least effective solvent in this study. This study can help to the clinicians about which solvent should be preferred for solving the filling materials in retreatment cases.

Sealing properties of three resin-based sealers

To evaluate the sealing properties of three resin- based sealers, EndoREZ, RealSEAL and RealSEAL SE. Forthy-eight extracted human anterior teeth with single root and canal were prepared using ProTaper files with crown-down technique to F3. The teeth were filled with three sealer respectively with hot gutta- percha vertical condensation technique simulating the clinical situation. Leakage quantity was detected using computerized fluid filtration meter with 10 samples in each group. The cross section morphology of apical parts of roots of 5 mm was observed with scanning electron microscope and transmission electron microscope in 3 samples of each group, respectively. The leakage quantity of EndoREZ, RealSEAL and RealSEAL SE were (2.61±0.60), (1.43±0.11) and (1.76±0.18) µl/min, respectively. The gaps between the the sealer and the canal wall were increased in in order of RealSEAL, RealSEAL SE and EndoREZ. No obvious demineralized dentin under EndoREZ and the smear layer was not completed removed. The partly demineralized dentin was observed under RealSEAL and the smear layer was totally removed. The partly demineralized dentin was seen under RealSEAL SE and the majority of smear layer was removed. Among the three resin- based sealers, RealSEAL has the best sealing properties, followed by RealSEAL SE and EndoREZ.

Push-out Bond Strength of RealSeal SE and AH Plus after Using Different Irrigation Solutions

IntroductionThe aim of this investigation was to evaluate the influence of different endodontic irrigants (sodium hypochlorite [NaOCl], chlorhexidine [CHX], and EDTA) on the push-out bond strength of the obturation materials RealSeal SE (SybronEndo, Orange, CA) and AH Plus (Dentsply International Inc, York, PA). MethodsTwo hundred human root canals were prepared and divided into 2 groups according to the filling material (RealSeal SE vs AH Plus). Each group was subdivided into 5 groups according to the irrigation protocol (0.9% saline [control], 3% NaOCl, 3% NaOCl with saline, 17% EDTA, and 2% CHX). After obturation, roots were sliced into 1-mm discs for push-out assessment. Compressive loading was performed using an universal testing machine at a speed of 0.5 mm/min. Two-way analysis of variance and the Kruskal-Wallis test were performed for pair-wise comparisons to assess the differences between the experimental groups. ResultsAH Plus exhibited a significantly higher bond strength than RealSeal SE (mean = 2.53 and 1.53 MPa, respectively; P < .05), except with saline alone (P > .05). Within the AH Plus groups, no significant differences existed between the irrigants and saline alone (P > .05). The bond strength of RealSeal SE with saline alone or with NaOCl and saline did not differ from that of AH Plus with saline alone (P > .05). However, the push-out bond strength of RealSeal SE decreased by approximately half (P < .05 compared with RealSeal SE with saline alone) after rinsing with NaOCl alone, EDTA, or CHX. ConclusionsThe bond strength of RealSeal SE is highly influenced by the irrigant used.