Experimental Sealers Research Articles

Physicochemical properties of calcium silicate cement based endodontic sealers

AimTo mensure the physicochemical properties of three ceramic cement endodontic sealers AH Plus Bioceramic, Bio-C Sealer and Bio-C Sealer Ion+ with an epoxy resin sealer, AH Plus. Material and methodsThese properties were measured: hardening time (HT), dimensional change (DC), solubility (SL), flow (FL) and radiopacity (RD). The distilled water obtained from the SL test was analyzed with atomic absorption spectrometry. A sample calculation was made considering n = 5 repetitions for each experimental sealer evaluated. Statistical analysis was performed using one-way ANOVA and post hoc Tukey tests (p < 0.05). ResultsFor the HT, AH Plus (484 ± 2.76 min) and AH Plus Bioceramic (424 ± 1.23 min) set more slowly than of Bio-C Sealer (370 ± 4.50 min) and Bio-C Sealer Ion+ (380 ± 1.42 min) (p < 0.05). AH Plus Bioceramic (12.56 ± 2.71 %) was more soluble than Bio-C Sealer (6.69 ± 1.67 %), Bio-C Sealer Ion+ (5.67 ± 2.16 %) and AH Plus (0.15 ± 0.01 %) (p < 0.05). AH Plus (0.03 ± 0.01 %) had slight expansion while the cement-based sealers had shrinkage: AH Plus Bioceramic (−1.60 ± 0.63 %) and Bio-C Sealer (−1.38 ± 0.69 %), Bio-C Sealer Ion+ (−5.19 ± 1.23 %) (p < 0.05). Bio-C Sealer Ion+ (59.80 ± 0.86 mm) and Bio-C Sealer (58.60 ± 0.98 mm) had the highest flow compared with AH Plus (56.90 ± 0.56 mm) and AH Plus Bioceramic (49.50 ± 0.63 mm) (p < 0.05). AH Plus (9.17 ± 0.06 mmAl) and AH Plus Bioceramic (8.27 ± 0.84 mmAl) showed radiopacity values when compared with those of Bio-C Sealer (4.90 ± 0.08 mmAl) and Bio-C Sealer Ion+ (4.14 ± 0.05 mmAl) (p > 0.05). ConclusionIon release is inhered to these cement-based sealers and this result in calcium ion release.

Microstructural and Elemental Characterization of Root Canal Sealers Using FTIR, SEM, and EDS Analysis

Background: Root canal sealers and repair materials should have the desirable physical, chemical, and biological characteristics, and an antibacterial effect if possible. There is little information available on the biocompatibility of new sealers on the market. Fourier transform infrared spectroscopy (FTIR) can offer trustworthy data to examine chemical structures; another technique for revealing the elements in the constituents that may contribute to the cytotoxicity of these sealers is scanning electron microscopy (SEM), with the goal of elemental mapping utilizing energy-dispersive X-ray spectroscopy (EDX). Methodology: All the root canal sealers were mixed as per the manufacturers’ instructions and allowed to set in molds for 24 h. Then, the samples were placed into an incubator (Memmert GmbH + Co. KG, Schwabach, Germany for 72 h, in a moist environment to allow complete chemical setting of the sealers. The organic and inorganic components of the sample were identified using FTIR with the wavelength length in the infra-red region measuring 400–450 nm. The finely crushed samples were coated with gold metal; following that, the sealer samples were examined under a scanning electron microscope (SEM) at 5000×, 10,000×, and 20,000× magnification, followed by energy-dispersive X-ray spectroscopy. Results: The surfaces of BioRoot and DiaRoot sealers revealed a relatively uniform distribution of irregular micro-sized particles aggregated in clusters, with the particle size ranging from 1 to 65 µm and 0.4 to 55 µm, respectively. OneFill, iRoot, and CeraSeal demonstrated irregularly shaped particles with particle sizes of 0.5 to 105 µm, 0.5 to 195 µm, and 0.3 to 68 µm, respectively. The EDX microanalysis revealed that oxygen, calcium, and carbon were found in all the tested sealer materials. Silicone and zirconium were absent in DiaRoot, but DiaRoot contained fluoride and ytterbium. Moreover, aluminum was noted in DiaRoot, One Fill, and CeraSeal, and chloride was only observed in BioRoot. FTIR analysis revealed strong absorption bands at 666 cm−1 and 709 cm−1 in BioRoot. Bands at 739 cm−1, 804 cm−1, 863 cm−1, 898 cm−1, and 1455 cm−1 were observed in DiaRoot. Bands at 736 cm−1 and 873 cm−1 in OneFill suggested the presence of C-H bending. Similarly, bands were observed at 937 cm−1, 885 cm−1, 743 cm−1, and 1455 cm−1 in iRoot, representing C-H stretching. Conclusions: All root canal sealers had diverse surface morphologies that contained irregular, micro-sized particles that were uniformly distributed, and they lacked heavy metals. All the experimental sealers comprised mainly calcium, oxygen, and carbon.

Antibacterial activity and physicochemical properties of a sealer containing copaiba oil

This study aimed to evaluate the antimicrobial activity and physicochemical properties of a novel dual-cure endodontic sealer containing copaiba oil. The copaiba oil was obtained and characterized by gas chromatography (GC), and the minimum inhibitory concentration (MIC) was performed. The experimental sealers were formulated with copaiba oil concentrations of 0, 0.5, 1, and 2%, and the RealSeal™ (Sybron endo, Orange, USA) and AH Plus (Dentsply De Trey Gmbh, Konstanz, Germany) were used as the commercial references. The antimicrobial activity of the sealers was evaluated by the direct contact test for 1h and 24h. To evaluate the physicochemical properties of the sealers, the degree of conversion, setting time, film thickness, dimensional stability, and radiopacity tests were performed. The data were statistically analyzed by one-way ANOVA and Tukey’s test (α = 0.05). Concerning the results, the sealers containing copaiba oil showed antimicrobial activity without harming the physicochemical properties.

Comparison of dimensional stability and pH of experimental root canal sealer with commercially available root canal sealers: An in vitro study

ABSTRACT Aim: The goal of the study is to evaluate and compare the pH and dimensional stability of the experimental root sealer to those of existing root sealers commonly used in endodontic therapy. Methods: The study samples were produced using commercially available sealers as well as experimental sealers containing nanoparticles. The pH was measured using a digital pH meter (accuracy of 0.01). Before each pH measurement, the pH meter’s accuracy was calibrated with a solution. Once the relevant dimension samples were generated, the dimensional stability of the materials was evaluated. L 30 - L/L × 100 was the formula used to calculate the percentage of dimensional change. Results: The Apexit Plus demonstrated a 1.33% expansion compared to the experimental sealer’s 0.43%. The contraction was 0.37% for AH Plus. The mean pH of the experimental root canal sealer utilized at various periods of immediate, 24 h and 1 week after is 9.51, 8.48, and 8.17. The mean pH of the AH Plus root canal sealer immediately, 24 h and 1 week was 8.30, 7.70, and 6.80, respectively. Conclusion: Within the constraints of the studies, the experimental sealer had stronger pH and dimensional stability than commercially available sealers. In vivo studies can be performed to reassess the qualities.

Penetration of Three Endodontic Sealers in Simulated Lateral Canals during the Lateral Condensation Technique: An In Vitro Study.

This study aimed to compare the penetration depths of AH Plus, BioRoot RCS, and GuttaFlow 2 into simulated lateral canals when used with the cold gutta-percha lateral compaction technique. Twelve resin training blocks (4 canals perch each resin block) were used. Each primary artificial canal had two lateral canals (apical and coronal). The main canals were instrumented with WaveOne Gold and irrigated with distilled water. The resin blocks were divided into three groups (N = 4 each/16 artificial canals), according to the type of root canal sealer; Group I: AH Plus, Group II: BioRoot RCS, and Group III: GuttaFlow 2. All canals were obturated with the cold lateral condensation technique. The linear extension of each endodontic sealer into the apical and coronal lateral canals was measured using a digital stereomicroscope and measuring software. Data were statistically analyzed using a one-way analysis of variance. The percentages of filling of the lateral canals were calculated and statistically compared using the Mann-Whitney test. The experimental sealers exhibited variable penetration depths into the lateral canals. All sealers showed significantly better penetration ability into the apical lateral canals than the coronal lateral canals (P < 0.05). AH Plus (3.184 ± 0.012 mm/99.5%) and GuttaFlow 2 (3.176 ± 0.017 mm/99.25%) were significantly better than BioRoot RCS (3.096 ± 0.026 mm/96.75%) in filling the apical lateral canals (P < 0.05). BioRoot RCS was the best sealer to fill coronal lateral canals (3.322 ± 0.085 mm/83.05%). During the lateral condensation technique, the filling of the lateral canals is affected by the type of root canal sealer and the location of the lateral canals All the sealers tested have a good ability to fill the apical lateral, while BioRoot RCS was effective in filling both the coronal and apical lateral canals.

Setting Time and Solubility of Thymol Incorporated Zinc Oxide-Guaiacol Root Canal Sealer: An in Vitro Study

Aims: This study aimed to establish whether changes in setting time and solubility of the locally prepared zinc oxide-guaiacol endodontic sealer when incorporated with thymol crystals as an antibacterial agent. Materials and Methods: zinc oxide-guaiacol endodontic sealer with thymol crystals incorporated at three different concentrations (2%, 5%, and10%) were tested, For setting time test similar specimens were prepared using ring molds with an internal diameter of (10 mm) and a height of (2 mm), nearly (120±10) seconds once mixing, the sample was located on a metal block in an incubator. A Gilmore needle with a mass of (100±0.5 g) which had (2±0.1 mm measurement) was used; the period of “no indent” was noted from the start of mixing. For the solubility test, similar specimens were prepared using ring molds with an internal diameter of (20 ± 0.1 mm) and a height of (1.5 ± 0.1 mm) and digitally weighted to register the mass of each specimen before and after immersion in distilled water. Solubility was determined after 24 hours and statistically analyzed using descriptive statistics, a One-Way ANOVA test, and post-hoc Duncanʼs Multiple Range Test was used. Results: The means of setting time of three experimental sealers were decreased as thymol crystal concentrations increased and the means of solubility for three experimental sealers were increased as the concentrations of thymol crystal increased. Conclusions: This study concluded that the prepared sealers with three concentrations were still adapted within the requirements of ANSIADA specifications NO.572008 for root canal sealer materials.

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

BackgroundFreshly 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.MethodsExperimental 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.ResultsAll 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.ConclusionsAddition 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.

Biological and antimicrobial properties of the association Ambroxol and a water-soluble viscous liquid as a vehicle for a tricalcium silicate-based sealer

This study aimed to investigate the antimicrobial and biological properties of Ambroxol associated with glycerin (GLI), propylene glycol (PG), and polyethylene glycol (PEG) as a possible vehicle for an experimental tricalcium silicate sealer, with the intention of developing a new biomaterial. Mouse undifferentiated dental pulp cells (OD-21) were cultured, and the effects of different association on cell proliferation and inflammatory cytokine production were investigated. Antimicrobial adhesion of Enterococcus faecalis to setting sealers at 2 h was evaluated. Polyethylene tubes containing experimental sealers and empty tubes were implanted into dorsal connective tissues of 12 male 3- to 4-months-old Wistar rats (250–280 g). After 7 and 30 days, the tubes were removed and processed for histological and immunohistochemical analyses. ANOVA followed by Bonferroni correction and ANOVA followed by Tukey test was used for parametric data and Kruskal–Wallis followed by Dunn for nonparametric (p < 0.05). Cell proliferation was dose-dependent, since all association were cytotoxic at higher concentrations; however, Ambroxol–PEG showed significantly higher cytotoxicity than other association (p < 0.05). In addition, irrespective of the association, no cytokine production was observed in vitro. Ambroxol–GLI reduced bacterial viability, whereas Ambroxol–PEG increased (p < 0.05). Histological examination showed no significant difference in the inflammatory response (p > 0.05) and mineralization ability in all association. Additionally, IL-1β and TNF-α were upregulated on Ambroxol–PEG in relation to Control at 07 days (p < 0.05). Ambroxol–GLI was the best vehicle for experimental tricalcium silicate sealer, as it promoted an increase in antimicrobial activity without altering the inflammatory response or mineralization ability.

Assessment of Root Canal Sealers Loaded with Drug-Silica Coassembled Particles Using an In Vitro Tooth Model

IntroductionThe purpose of this study was to assess the antimicrobial activity of root canal sealers modified with novel highly loaded antimicrobial drug-silica coassembled particles (DSPs) on Enterococcus faecalis–infected root canal dentin. MethodsDSPs were synthesized through coassembly of silica and octenidine dihydrochloride (OCT) surfactant drug (35% w/w OCT). DSPs (1% wt of the total mass of the sealer) were mixed homogenously with either epoxy resin sealer (AH Plus [AH]; Dentsply Sirona, Tulsa, OK) or calcium silicate–based sealer (EndoSequence BC Sealer [BC]; Brasseler, Savannah, GA). To assess the antimicrobial activity of DSP-loaded sealers, the apical third of single-rooted teeth was obtained and infected with E. faecalis for 3 weeks followed by the application of experimental (DSP-loaded) sealers or corresponding controls for up to 28 days. Microbiological analysis and laser scanning confocal and scanning electron microscopy were used to determine the colony-forming unit (CFU)/mL, the percentage of live bacteria, and the intratubular bacterial and sealer penetrations. Factorial analysis of variance and Tukey post hoc tests were used to assess the antimicrobial effect of DSPs on different sealers. ResultsAll experimental groups showed significant reductions in CFUs at all-time points compared with positive controls (P < .05). The addition of DSPs to BC significantly reduced the CFUs (2.11 ± 0.13, 2.22 ± 0.19, and 2.25 ± 0.17 at 1, 7, and 28 days, respectively) compared with the unmodified sealer (3.21 ± 0.11, 4.3 ± 0.15, and 4.2 ± 0.2 at 0, 7, and 28 days). DSPs enhanced the antimicrobial performance of AH only at 1 day (4.21 ± 0.17 vs 5.19 ± 0.12, P < .05). AH and AH + DSPs showed higher bacterial viability compared with BC and BC + DSPs at all incubation periods (P < .05). ConclusionsLoading endodontic sealers with DSPs had a material-dependent effect on the antimicrobial properties and could reduce the incidence of secondary infections.

Investigation of characteristics as endodontic sealer of novel experimental elastin-like polypeptide-based mineral trioxide aggregate

Although mineral trioxide aggregates (MTA) have been adopted as an endodontic sealer because of excellent sealing effect and bioactive property and been modified with improvement of its characteristics, the developed MTA sealers have not yet satisfied all the ideal requirements of endodontic sealers. The aim of this study was to assess the characteristics of elastin-like polypeptide (ELP)-incorporated MTA for use as an endodontic sealer and compare them with those of commercial MTA sealers. Two commercial MTA sealers and three experimental ELP-incorporated MTA sealers with 0.3, 0.4, and 0.5 liquid/powder (L/P) ratio for 10 wt% ELP liquid were evaluated. The push-out bond strength, flow rate, sealer penetrability and wash-out resistance were tested and the sealer-dentin interface was observed using a scanning electron microscope (SEM). Our study revealed the ELP-incorporated MTA sealer, especially in 0.4 L/P ratio, exhibited the higher push-out bond strength and flow rate (P < 0.05), and equal or superior sealer penetration and remarkable wash-out resistance compared to commercial MTA sealers. The groups of ELP-based experimental sealers also exhibited more intimate contact with dentin compared to the commercial MTA sealers. Our research will suggest the possible adoption of the ELP-incorporated MTA as endodontic sealer for clinical use.

In-Vitro Comparative Adhesion Evaluation of Bioceramic and Dual-Cure Resin Endodontic Sealers Using SEM, AFM, Push-Out and FTIR

(1) Background: Which are the adhesion characteristics of four root canal sealers: two experimental (dual cure resin based endodontic sealer (E1-DCR) and bioceramic based sealer (E2-BC)), and two commercial (RealSeal and TotallFill BC (FKG Germany)). (2) Methods. One-hundred-twenty extracted monoradicular teeth received mechanic-antiseptic preparation and then endodontic filling using gutta-percha in combination with one of the four sealers. Samples from the apical third were selected from each tooth and were randomly distributed for Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and push-out bond strength. Fourier Transform Infrared (FTIR) Spectroscopy was made exclusively for experimental sealers. (3) Results. The two experimental materials did not present a significant difference in apical sealing ability based on SEM evaluation. Gaps were identified in case of RealSeal samples and also lower penetration into the dentinal tubules compared to TotalFill BC. On AFM analysis a more pronounced penetration into the tubules was observed in case of E2-BC sealer was observed. E1-DCR registered a lower bond strength (0.7177 ± 0.55) in the apical third compared to Total Fill BC (p = 0.01). (4) Conclusions. Within the limitations of the current study, it can be stated that the two experimental sealers’ characteristics are comparable to that of the two consecrated materials.

Antimicrobial and physical properties of experimental endodontic sealers containing vegetable extracts

To assess the antimicrobial activity and the physical properties of resin-based experimental endodontic sealers with the incorporation of vegetable extracts obtained from Bixa orellana, Mentha piperita, and Tagetes minuta species. The extracts were obtained and characterized by gas chromatography-mass spectrometry (GC–MS), and minimum inhibitory concentration (MIC) against Streptococcus mutans, Enterococcus faecalis, and Candida albicans. The extracts were individually incorporated into a dual-cure experimental sealer at a mass concentration of 0.5%. A commercial reference RealSeal was used. The sealers were evaluated by measuring the setting time, degree of conversion, dimensional stability, radiopacity, flow, and film thickness of these materials, also and its antimicrobial effect was evaluated using the direct contact test. Data were statistically analyzed by analysis of variance and Tukey’s post-hoc test at α = 0.05 significance level. The physical properties were not influenced by the addition of the vegetable extracts (p > 0.05). For S. mutans, only T. minuta and B. orellana groups presented antibacterial activity after 24 h of contact (p < 0.05). All extracts evidenced an antibacterial effect against E. faecalis (p < 0.05). The experimental sealers hold promise as a novel vegetable sealer with great antimicrobial activity and also great physical–mechanical properties. Nonetheless, more studies are needed.

Biological Properties of Experimental Methacrylate-Based Sealers Containing Calcium Phosphates.

This study aimed to evaluate, in vitro and in vivo, the biocompatibility of experimental methacrylate-based endodontic sealers containing α-tricalcium phosphate (α-TCP) or nanostructured hydroxyapatite (HAp). Experimental methacrylate-based dual-cure sealers with the addition of α-TCP or HAp, at 10%wt were formulated and compared to AH Plus (AHP). Cell viability was assessed by 3-(4,5-dimethyl-thiazoyl)-2,5-diphenyl-tetrazolium bromide (MTT), and sulforhodamine B (SRB). Sealers were implanted in rats' subcutaneous tissue and histologically evaluated. Bioactivity was assessed by alkaline phosphatase enzyme activity (ALP) and Alizarin Red (AR), using apical papillary cells (SCAPs), and by the bone deposition measured in surgical cavities on rats' femur filled with AH Plus or α-TCP. In both viability assays, HAp and AHP sealers were similar, and α-TCP presented lower viability compared to the others at MTT assay (p<0.05). A gradual decrease of the inflammatory response according to the periods was observed and AHP was the only that presented giant cells (7-day period). Collagen fibers condensation increased according to the periods, with no differences among sealers. There was an increase at ALP activity and mineralized nodules deposition according to periods. HAp and α-TCP presented higher values for ALP activity at 5 days and at 5, 10, and 15 days for AR and were different from AHP (p<0.05). α-TCP presented superior values at 10 and 15 days compared to HAp and AHP for AR (p<0.05). At 90 days, α-TCP and control (empty cavity) showed high bone deposition compared to AHP (p<0.05). α-TCP and HAp, in a methacrylate-based sealer, presented biocompatibility and bioactivity, with the potential to be used as endodontic sealers in clinical practice. Further investigations are required to gain information on the physicochemical properties of these sealers formulation before its clinical implementation.

Behaviour of different bioactive glasses incorporated in polydimethylsiloxane endodontic sealer

ObjectivesThe aim of this study was to analyze the behavior of different bioactive glass fillers (BAGs) embedded in a polydimethylsiloxane matrix of an endodontic sealer. MethodsThree different endodontic sealers were fabricated using S53P4, 45S5 and 18−06 glass fillers. Endodontic sealer Guttaflow Bioseal consisting of polydimethylsiloxane (PDMS) matrix was used as base of the experimental sealers. Behaviors of different glass fillers leaching from polymer matrix was studied in vitro for 14 days by measuring static ion dissolution profiles of Si, Na, Ca and P -ions. In addition, pH of the simulated bodyfluid (SBF) was monitored during the 14 days and all the sealer samples was examined with SEM/EDX analysis on the surface. Identical but non-glass filler containing polydimethylsiloxane-based sealer was used as a control material. ResultsBy the time point of 24 h sealer with 45S5 had released twice as much of Si-ions compared to sealer with S53P4. No statistical differences of Na, Ca and P -ions dissolution were observed in the first 168 h for any groups whereas concentrations of Ca and P -ions decreased with 45S5 significantly after 336 h. Highest pH was measured for sealers with glass filler 45S5 and S53P4 (7.64–7.65). Visible mineral precipitation was observed only on sealer surfaces after 336 h’ time period with groups of 45S5 and S53P4. However, presence of calcium and phosphorus oxides was confirmed only with 45S5. SignificanceBioactive glass type 45S5 outperforms S53P4 and 18−06 by acting more dynamically in vitro set-up

Bone repair in defects filled with AH Plus sealer and different concentrations of MTA: a study in rat tibiae.

ObjectivesThis study aimed to evaluate the effects on bone repair of different concentrations of mineral trioxide aggregate (MTA) added to AH Plus.Materials and MethodsBone tissue reactions were evaluated in 30 rats (Rattus norvegicus) after 7 and 30 days. In the AH + MTA10, AH + MTA20, and AH + MTA30 groups, defects in the tibiae were filled with AH Plus with MTA in proportions of 10%, 20% and 30%, respectively; in the MTA-FILL group, MTA Fillapex was used; and in the control group, no sealer was used. The samples were histologically analyzed to assess bone union and maturation. The Kruskal-Wallis and Mann-Whitney tests were performed for multiple pairwise comparisons (p ≤ 0.05).ResultsAt the 7-day time point, AH + MTA10 was superior to MTA-FILL with respect to bone union, and AH + MTA20 was superior to MTA-FILL with respect to bone maturity (p < 0.05). At the 30-day time point, both the AH + MTA10 and AH + MTA20 experimental sealers were superior not only to MTA-FILL, but also to AH + MTA30 with respect to both parameters (p < 0.05). The results of the AH + MTA10 and AH + MTA20 groups were superior to those of the control group for both parameters and experimental time points (p < 0.05).ConclusionsThe results suggest the potential benefit of using a combination of these materials in situations requiring bone repair.

A Novel Bioactive Endodontic Sealer Containing Surface-Reaction-Type Prereacted Glass-Ionomer Filler Induces Osteoblast Differentiation.

Surface-reaction-type prereacted glass-ionomer (S-PRG) fillers exhibit bioactive properties by the release of multiple ions. This study examined whether a novel endodontic sealer containing S-PRG fillers (PRG+) has the capacity to induce osteoblast differentiation. Kusa-A1 osteoblastic cells were cultured with extracts of PRG+, PRG− (an experimental sealer containing S-PRG-free silica fillers), AH Plus (an epoxy-resin-based sealer), and Canals N (a zinc-oxide noneugenol sealer). Cell viability and mineralized nodule formation were determined using WST-8 assay and Alizarin red staining, respectively. Osteoblastic-marker expression was analyzed with RT-qPCR and immunofluorescence. Phosphorylation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) was determined with Western blotting. Extracts of freshly mixed PRG+, PRG−, and AH Plus significantly decreased cell growth, but extracts of the set samples were not significantly cytotoxic. Set PRG+ significantly upregulated mRNAs for alkaline phosphatase and bone sialoprotein (IBSP) compared to set PRG−, and upregulation was blocked by NPS2143, a calcium-sensing receptor antagonist. Set PRG+ significantly accelerated IBSP expression, mineralized nodule formation, and enhanced the phosphorylation of ERK and p38 compared with set PRG−. In conclusion, PRG+ induced the differentiation and mineralization of Kusa-A1 cells via the calcium-sensing receptor-induced activation of ERK and p38 MAPK.

Evaluation of the biological properties of two experimental calcium silicate sealers: an in vivo study in rats.

To evaluate the biological properties of experimental sealers based on tricalcium silicate and dicalcium silicate, manipulated with polyethylene glycol (CE-1) and with the addition of calcium hypochlorite (CE-2) compared to AH Plus (AHP) and TotalFill BC Sealer (TBC). The tissue reaction caused by the materials in the subcutaneous tissue of rats was evaluated after implantation of polyethylene tubes filled with the materials at 7, 15, 30 and 60days. Sections were stained with haematoxylin and eosin (HE) for morphological analysis and to evaluated number of inflammatory cells/mm2 (ICs). Sections were used for immunohistochemical detection of interleukin-6 (IL-6) and osteocalcin (OC). The von Kossa method was used to identify calcium precipitation in the capsules. The data were submitted to anova and Tukey's tests, with 5% significance level. At 7days, CE-1, CE-2 and AHP had higher numbers of ICs. AHP presented higher immunolabelling for IL-6. After 15days, regarding IL-6, there was no difference between CE-2 and the control group. At 30days, AHP exhibited the highest number of IC (P<0.05) and CE-2 and the control group presented the lowest ICs and IL-6-positive cells. After 60days, all materials exhibited decreases in ICs. CE-2, TBC and the control had the lowest values (P<0.05). No significant difference was detected between CE-1 and TBC, and between CE-2 and control considering the immunoexpression of IL-6. In this period, AHP had the greatest number of IC and IL-6 (P<0.05). In all periods, CE-1, CE-2 and TBC sealers had von Kossa-positive structures and OC-immunolabelled cells. CE-2 had higher number of OC-positive cells than the CE-1 and TBC sealers (P<0.05), in all periods. OC immunolabelling was not observed in the capsules of AH Plus and the control groups. The experimental sealer and its association with calcium hypochlorite, in addition to TotalFill BC Sealer, were biocompatible and had bioactive potential.

Impact of Irrigation Solutions on the Apical Sealing Potential of Different Endodontic Sealers Used with the Continuous-wave Obturation Technique: An In vitro Study

Abstract Aim: This study is aimed to evaluate the impact of three irrigating solutions on the apical sealing ability of three endodontic sealers. Materials and Methods: One hundred maxillary central incisors were decoronated, and their roots were assigned into three experimental groups (n = 30 each) according to the nature of the irrigating solution and two control groups (n = 5 each). Each experimental group was divided equally into three subgroups (n = 10 each) according to the type of root canal sealer. All root canals were instrumented using ProTaper Universal rotary system and irrigated with 3% sodium hypochlorite (NaOCl/Group 1), 3% hydrogen peroxide (H2O2/Group 2), and 2% chlorhexidine gluconate (CHX/Group 3). The final irrigating solutions for all groups were 17% ethylenediaminetetraacetic acid (EDTA) and distilled water. The continuous-wave technique was used to fill the prepared canals with the following materials: MTA-Fillapex/Gutta-percha (Subgroup A), AH Plus/Gutta-percha (Subgroup B), and Realseal SE/Realseal (Subgroup C). The microleakage was assessed after 72 hours using the linear dye penetration method. The results were statistically analyzed with one-way analysis of variance. Results: Significant differences were found only between the experimental groups (P &lt; 0.05). All root canal sealers after irrigation with 3% H2O2 showed the lowest amount of leakage. The highest apical leakage was observed when 3% NaOCl and 2% CHX were used. Conclusions: The type of irrigating solution could affect the apical sealing ability of experimental sealers used with the continuous-wave obturation technique. Root canal irrigation with 3% H2O2 +17% EDTA increased the apical sealing ability of all root canal sealers. Root canal irrigation with 3% NaOCl or 2% CHX +17% EDTA decreased the apical sealing ability of all root canal sealers.

Physico-chemical and antimicrobial properties and the shelf life of experimental endodontic sealers containing metal methacrylates

The objective of this study was to evaluate the physico-chemical and antimicrobial properties of a dual polymerization experimental endodontic sealer (E) and experimental sealers containing dibutyltin methacrylate (Sn2+) (ETs) or calcium methacrylate (Ca2+) (ECs). The pH and ion release levels of the sealers were measured. The dimensional stability was evaluated in accordance with ISO 6876. Biofilm growth inhibition was evaluated using confocal laser scanning microscopy (CLSM). Biofilm viability analysis was performed using the SYTO 9 technique. The shelf life was evaluated through the degree of conversion and film thickness tests after the sealers had been stored for different periods of time. For statistical analysis, ANOVA and Tukey’s post hoc test were used, with a significance level of 5%. ETs revealed better anti-biofilm potential after 15 days than that of the controls. The degree of conversion was reduced after the shelf-life period. The addition of calcium and dibutyltin methacrylate improved the anti-biofilm properties of the experimental endodontic sealer without impairing their physico-chemical properties.

Structural, fluoride release, and 3D interfacial adhesion analysis of bioactive endodontic sealers.

The experimental bioactive sealers were synthesized by incorporating fluoridated-nano-bioactive glass (F-nBG; 2.5 and 5wt%) in AH Plus® (Dentsply DeTrey, Konstanz, Germany) sealer and denoted as AH-FBG2.5 and AH-FBG5, respectively. Structural pattern, setting time, flowability, and water sorption analysis were performed. The fluoride release behavior was evaluated periodically over the course of 40 days using inductively coupled plasma optical emission spectroscopy. For sealing ability, post-extraction single-rooted teeth were obturated with sealers. The percentage of voids and sealing ability were evaluated periodically using micro-computed tomography (micro-CT) followed by push-out bond strength. The Fourier transform infrared spectra showed a change in peak height with an increase in the concentration of fillers. The setting time, flowability, and water sorption of experimental groups were within the acceptable clinical range. The fluoride release, sealing ability, and bond strength of experimental sealers were significantly high. The experimental sealers have potential to overcome sealing ability issues of sealers.