Chemical composition and bioactivity potential of the new Endosequence BC Sealer formulation HiFlow

Premixed calcium silicate-based ceramic sealers promote osteogenic/cementogenic differentiation of human periodontal ligament stem cells: A microscopy study

To evaluate the effects of premixed calcium silicate based ceramic sealers on the viability and osteogenic/cementogenic differentiation of human periodontal ligament stem cells (hPDLSCs). The materials evaluated were TotalFill BC Sealer (TFbc), AH Plus Bioceramic Sealer (AHPbc), and Neosealer Flo (Neo). Standardized discs and 1:1, 1:2, and 1:4 eluates of the tested materials were prepared. The following in vitro experiments were carried out: ion release, cell metabolic activity 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell migration, immunofluorescence experiment, cell attachment, gene expression, and mineralization assay. Statistical analyses were performed using one-way ANOVA followed by Tukey's post hoc test (p < .05). Increased Ca2+ release was detected in TFbc compared to AHPbc and Neo (*p < .05). Biological assays showed a discrete cell metabolic activity and cell migration in Neo-treated cell, whereas scanning electronic microscopy assay exhibited that TFbc group had a better cell adhesion process of substrate attachment, spreading, and cytoskeleton development on the niche-like structures of the cement than AHPbc and Neo. The sealers tested were able to induce overexpression of the CEMP-1, ALP, and COL1A1 genes in the first days of exposure, particularly in the case of TFbc (***p < .001). All materials tested significantly increased the mineralization of hPDLSCs when compared to the negative control, although more pronounced calcium deposition was observed in the TFbc-treated cells (***p < .001). Our results suggested that TFbc promotes cell differentiation, both by increasing the expression of key osteo/odontogenic genes and by promoting mineralization of the extracellular matrix, whereas this phenomenon was less evident in Neo and AHPbc. RESEARCH HIGHLIGHTS: TFbc group had a better cell adhesion process of substrate attachment, spreading, and cytoskeleton development on the niche-like structures of the cement than AHPbc and Neo. The sealers tested were able to induce overexpression of the CEMP-1, ALP, and COL1A1 genes in the first days of exposure, particularly in the case of TFbc. All materials tested significantly increased the mineralization of hPDLSCs when compared to the negative control, although more pronounced calcium deposition was observed in the TFbc-treated cells.

Three-dimensional assessment of obturation volume in lateral canals after three obturation techniques with bioceramic sealer: an in vitro comparative study

OBJECTIVE

This study aimed to evaluate the obturation ability of simulated lateral canal in mandibular premolars at three levels (3, 5, and 7 mm) from the apex using gutta-percha and BC Sealer HiFlow (BCHiF) with different obturation techniques, including continuous wave compaction (CWC), cold lateral condensation (CLC), and single cone (SC) techniques, by a 3D assessment method of the obturation volume with cone beam computed tomography (CBCT) and MIMICS software analysis.

METHODS

Thirty intact human mandibular premolars were decoronated, instrumented up to #30 taper 4%, and uniformly irrigated with 5.25% NaOCl and 17% EDTA. Six simulated lateral canals (3 pairs) were prepared at 3, 5, and 7 mm from the apex in each root, using #10 modified C-file. CBCT images were obtained, and lateral canal volumes were calculated using MIMICS software. The samples were divided into three groups: CWC (n = 10), CLC (n = 10), and SC (n = 10). All groups were obturated with BCHiF and gutta-percha. Another CBCT image was taken post-obturation, and 3D lateral canal obturation volume percentages were calculated using MIMICS software. Data were analyzed using SPSS software with One-way ANOVA and Sidak tests (α = 0.05).

RESULTS

Significant differences were observed in the 3D lateral canal obturation volume percentage at all three levels (P < 0.05). Both CWC and CLC techniques demonstrated higher 3D lateral canal obturation volume percentages (x ¯  = 89.64% andx ¯   =  73.28%; respectively) compared to the SC group)x ¯   =  43.10%).

CONCLUSION

BCHiF combined with the CWC technique has a higher ability to achieve preferable 3D obturation volume in the simulated lateral canal at 3, 5, and 7 mm.

CLINICAL RELEVANCE

In cases requiring endodontic treatment with lateral canals, the CWC obturation technique using BCHiF with gutta-percha may offer better outcomes compared to other obturation techniques.

Premixed calcium silicate-based root canal sealers have better biological properties than AH Plus: A systematic review and meta-analysis of in vivo animal studies and in vitro laboratory studies

Objectives

The aim was to determine whether premixed calcium silicate-based root canal sealers have better biological properties than AH Plus.

Materials and Methods

Searches of studies published up to January 2023 were performed in the PubMed/MEDLINE and EMBASE and via other methods (databases of the International Endodontic Journal, Journal of Endodontics, and gray literature). The inclusion criteria were in vivo animal and in vitro studies that analyzed the response in the dorsal subcutaneous tissue of rats, cell viability, and genotoxicity. Systematic Review Centre for Laboratory Animal Experimentation Risk of Bias (RoB) tool for in vivo studies and modified CONSORT checklist for in vitro were appraised. Meta-analysis was performed using the Stata.

Results

Fifty-two studies were included. In the RoB, in vivo studies fulfilled 20%-50% of the items and in vitro 60%-100%. The studies included in the meta-analysis demonstrated better histocompatibility with the premixed calcium silicate-based sealers at 30 days and greater cell viability with these sealers when used in undiluted extracts in experimental period of 72 h and in extracts with 1:2 and 1:4 dilution in 24 and 72 h. In contrast, no difference between materials was found concerning genotoxicity.

Conclusion

Premixed calcium silicate-based root canal sealers have better histocompatibility and are less cytotoxic than the epoxy resin-based sealer AH Plus, demonstrating favorable biological behavior.

Comparative bioactivity and immunomodulatory potential of the new Bioroot Flow and AH Plus Bioceramic sealer: An in vitro study on hPDLSCs

OBJECTIVES

To evaluate the cytocompatibility, bioactivity, and anti-inflammatory potential of the new pre-mixed calcium silicate cement-based sealers Bioroot Flow (BrF) and AH Plus Bioceramic Sealer (AHPbcs) on human periodontal ligament stem cells (hPDLSCs) compared to the epoxy resin-based sealer AH Plus (AHP).

MATERIALS AND METHODS

Standardized discs and 1:1, 1:2, and 1:4 eluates of BrF, AHPbcs and AHP after setting were prepared. The following assays were performed: cell attachment and morphology via SEM, cell viability via a MTT assay, cell migration/proliferation via a wound-healing assay, cytoskeleton organization via immunofluorescence staining; cytokine release via ELISA; osteo/cemento/odontogenic marker expression via RT-qPCR, and cell mineralized nodule formation via Alizarin Red S staining. HPDLSCs were isolated from extracted third molars from healthy patients. Comparisons were made with hPDLSCs cultured in unconditioned (negative control) or osteogenic (positive control) culture media. Statistical significance was established at p < 0.05.

RESULTS

Both BrF and AHPbcs showed significantly positive results in the cytocompatibility assays (cell metabolic activity, migration, attachment, morphology, and cytoskeleton organization) compared with a negative control group, while AHP showed significant negative results. BrF exhibited an upregulation of at least one osteo/cementogenic marker compared to the negative and positive control groups. BrF showed a significantly higher calcified nodule formation than AHPbcs, the negative and positive control groups, while AHPbcs was higher than the negative control group. Both were also significantly higher than AHP group.

CONCLUSION

BrF and AHPbcs exhibit adequate and comparable cytocompatibility on hPDLSCs. BrF also promoted the osteo/cementogenic differentiation of hPDLSCs. Both calcium silicate-based sealers favored the downregulation of the inflammatory cytokine IL-6 and the calcified nodule formation from hPDLSCs. BrF exerted a significantly higher influence on cell mineralization than AHPbcs.

CLINICAL RELEVANCE

This is the first study to elucidate the biological properties and immunomodulatory potential of Bioroot Flow and AH Plus Bioceramic Sealer. The results act as supporting evidence for their use in root canal treatment.

A comparative study of biological properties of three root canal sealers

OBJECTIVES

The aim of this study was to evaluate the effects of Hiflow with other two kinds of root canal sealers on the biological behavior of stem cells from the apical papilla (SCAP), the influence on inflammatory cytokines release and its antibacterial effects.

MATERIALS AND METHODS

Material extracts of Hiflow, iRoot SP, and AH Plus were prepared. Then, SCAP was incubated with extracts. The effects were evaluated by CCK-8, wound healing assay, ALP staining, alizarin red staining, and qRT-PCR. Meanwhile, polymorphonuclears (PMNs) and monocytes were isolated and treated with extracts for 4 h and 24 h respectively. Cell viability was analyzed by Annexin-V/PI double staining flow cytometry. The effects on the release of cytokines were observed by ELISA. The antibacterial effects of different sealers were tested against three kinds of bacteria found in chronic apical periodontitis.

RESULTS

A series of results of SCAP showed that Hiflow and iRoot SP could promote cell proliferation, migration, and osteogenesis (p < 0.05). Although Hiflow was associated with greater cell apoptosis and necrosis when incubated with PMNs and monocytes (p < 0.05), it had an approximate release of anti-inflammatory cytokines with iRoot SP, which was higher than AH plus (p < 0.05). The co-culture showed that Hiflow and iRoot SP inhibited the colony formation of F. nucleatum (p < 0.05). However, both sealers had no obvious antibacterial effect on E. faecalis and P. gingivalis (p > 0.05).

CONCLUSIONS

In summary, Hiflow and iRoot SP both had positive biological stimulus on SCAP. Meanwhile, Hiflow showed a better induction on anti-inflammatory cytokines over the others. All the properties mentioned above and its antibacterial effect of F. nucleatum promise Hiflow a bright application prospect in endodontic uses.

CLINICAL RELEVANCE

References for clinical work to use BC Sealer Hiflow as a good biological root canal sealer.

A comparison of osteogenic effect of newly manufactured calcium silicate-based sealers in vitro

This study aimed to assess the effect of different calcium silicate-based root canal sealers (CSRS) on osteogenic effect in human periodontal ligament cells (hPDLCs). hPDLCs were cultured in a medium containing extract of 5 types of CSRS. The specimens were assessed by the cell cytotoxicity test, alkaline phosphatase staining, alizarin red S staining, quantitative real-time PCR, Western blot analysis, and enzyme-linked immunosorbent assay. The diluted concentrations of extracted solutions had no significant effect on the viability of hPDLCs. There was a statistically significant difference in the mRNA expression level of bone sialoprotein (BSP), osteocalcin (OCN), and runt-related transcription factor 2 (RUNX2) among some groups. The protein expressions of BSP, OCN, and RUNX2 were significantly higher in some groups compared to the control group. The CSRS did not interfere with the osteogenic differentiation of hPDLCs, compared to the control group. CSRS are shown to have biocompatibility and osteogenic differentiation effect on hPDLCs.

Sol-Gel Technologies to Obtain Advanced Bioceramics for Dental Therapeutics

The aim of this work is to review the application of bioceramic materials in the context of current regenerative dentistry therapies, focusing on the latest advances in the synthesis of advanced materials using the sol-gel methodology. Chemical synthesis, processing and therapeutic possibilities are discussed in a structured way, according to the three main types of ceramic materials used in regenerative dentistry: bioactive glasses and glass ceramics, calcium phosphates and calcium silicates. The morphology and chemical composition of these bioceramics play a crucial role in their biological properties and effectiveness in dental therapeutics. The goal is to understand their chemical, surface, mechanical and biological properties better and develop strategies to control their pore structure, shape, size and compositions. Over the past decades, bioceramic materials have provided excellent results in a wide variety of clinical applications related to hard tissue repair and regeneration. Characteristics, such as their similarity to the chemical composition of the mineral phase of bones and teeth, as well as the possibilities offered by the advances in nanotechnology, are driving the development of new biomimetic materials that are required in regenerative dentistry. The sol-gel technique is a method for producing synthetic bioceramics with high purity and homogeneity at the molecular scale and to control the surfaces, interfaces and porosity at the nanometric scale. The intrinsic nanoporosity of materials produced by the sol-gel technique correlates with the high specific surface area, reactivity and bioactivity of advanced bioceramics.

Hydraulic calcium silicate-based root canal sealers mitigate proinflammatory cytokine synthesis and promote osteogenesis in vitro

Background/purpose

The mineralized tissue-inductive ability and anti-inflammatory properties of hydraulic calcium silicate-based (HCSB) sealers have not been fully elucidated. This study aimed to evaluate the effects of the HCSB sealers Bio-C sealer (BioC), Well-Root ST (WST), and EndoSequence BC sealer (BC), on osteoblastic differentiation/mineralization and proinflammatory cytokine synthesis by macrophages.

Materials and methods

Diluted extracts of set sealers or calcium chloride solutions of approximately equivalent Ca2+ concentrations were applied to a mouse osteoblastic cell line (Kusa-A1 cells) and lipopolysaccharide-stimulated mouse macrophage cell line (RAW264.7 cells). Expressions of osteoblastic markers in Kusa-A1 cells and proinflammatory cytokines in RAW264.7 cells were evaluated by reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assays. Mineralized nodules were detected by Alizarin red S staining. Cell proliferation was assessed by WST-8 assay and cell attachment on set sealers was examined by scanning electron microscopy.

Results

The three sealer extracts significantly upregulated osteocalcin and osteopontin mRNA, and promoted significant mineralized nodule formation in Kusa-A1 cells. The three sealer extracts significantly downregulated the mRNA expressions of interleukin (IL)-1α, IL-1β, IL-6, and tumor necrosis factor (TNF)-α and protein levels of IL-6 and TNF-α in RAW264.7 cells. Calcium chloride solutions induced osteoblastic differentiation/mineralization. AH Plus Jet (a control sealer) extract did not. The three HCSB sealers did not interfere with the growth and attachment of Kusa-A1 cells.

Conclusion

BioC, WST, and BC were biocompatible, upregulated osteoblastic differentiation/mineralization, and downregulated proinflammatory cytokine expression. Ca2+ released from HCSB sealers might be involved, at least in part, in the induction of osteoblastic differentiation/mineralization.

A Review of the research methods and progress of biocompatibility evaluation of root canal sealers

The function of root canal sealer was to achieve an appropriate three-dimensional filling effect by filling the root canal and some irregular lumen, thereby inhibiting the residual bacteria. There were many types of sealers, but research to find the most suitable ones was still ongoing. In recent years, researchers had continuously improved the performance of sealers by developing new sealers or adding active ingredients to the sealers. However, most sealers exhibit varying degrees of cytotoxicity and tissue responses, which affect clinical therapy efficacy. This review describes different technical approaches, and recent research progress in the biocompatibility evaluation of root canal sealers and provides brief insights into this field by summarising the performance studies of different root canal sealers.

Clinical applications of calcium silicate-based materials: a narrative review

Calcium silicate-based materials are hydrophilic materials with biocompatibility and bioactivity properties. Despite many advantages, they might present some problems related to discolouration, setting time, manipulation and solubility depending on the composition of the product and the type of clinical application. Calcium silicate-based materials can be evaluated under two types according to their intended use: calcium silicate-based cements (CSCs) and calcium silicate-based sealers (CSSs). CSCs can be used in many endodontic procedures including perforation repair, resorption repair, apical barriers, guided endodontic repair, vital pulp treatment, endodontic surgery, root fractures and root canal filling as a core obturation material. CSSs are available for use with gutta-percha to obturate root canals using cold and warm techniques, including the sealer-based obturation technique. The purpose of this review is to evaluate the available literature on CSCs and CSSs and to provide up-to-date information and recommendations for their clinical applications.

Cytotoxicity and Mineralization Activity of Calcium Silicate-Based Root Canal Sealers Compared to Conventional Resin-Based Sealer in Human Gingival Fibroblast Cells

Background

Root canal obturation is performed by gutta-percha cones and sealer. Therefore, these materials, specially sealers, must be biocompatible. This study investigated the cytotoxicity and mineralization activity of two calcium silicate-based sealers (Endoseal MTA and Ceraseal) and an epoxy resin-based sealer (AH26).

Materials and Methods

In this experiment, the cytotoxicity of Endoseal MTA, Ceraseal, and AH26 on human gingival fibroblast cells was examined using Methyl-Thiazol-Tetrazolium assay at time intervals of 24, 48, 72, and 120 hr. The mineralization activity of sealers was evaluated by Alizarin red staining assay. Prism, ver.3, software was used to perform statistical tests. One-way analysis of variance analysis, followed by Tukey's test, was used to determine the group differences. P-values < 0.05 were considered statistically significant.

Results

Cytotoxicity of sealers decreased gradually (P < 0.0001). AH26 showed the highest level of cytotoxicity (P < 0.001). In terms of cytotoxicity, no considerable differences were observed between the two-calcium silicate-based sealers (P > 0.05). AH26 showed the lowest mineralization activity (P < 0.0001). Among the calcium silicate-based sealers, mineralization and formation of calcium nodules were more frequently observed in the Endoseal MTA group (P < 0.001).

Conclusion

The examined calcium silicate-based sealers had less cytotoxicity and higher mineralization activity than the resin-based sealer (AH26). There was negligible difference between the cytotoxicity of the two-calcium silicate-based, but the cell mineralization caused by Endoseal MTA was higher.

Physicochemical properties and biocompatibility of various bioceramic root canal sealers: in vitro study

INTRODUCTION

The aim of this study was to compare the physicochemical properties and biocompatibility of various calcium silicate-based bioceramic sealers (CSBSs).

METHODS

Four recently developed CSBSs, including AH Plus Bioceramic Sealer (AHB), EndoSequence BC Sealer (ESB), TotalFill BC Sealer (TTB), and Bio-C Sealer (BIC), were compared with the epoxy resin-based sealer AH Plus (AHP). Their physical properties, including flow, setting time, radiopacity, dimensional stability, and pH, were evaluated according to International Organization for Standardization (ISO) 6876. Their cytotoxicity in human periodontal ligament fibroblast (hPDLF) was assessed through the MTT assay and compared. Additionally, cell attachment to the sealer surface was analysed using green fluorescent protein and confocal laser scanning microscopy (CLSM) to evaluate cell viability. Data were analysed using one-way analysis of variance to determine the difference between groups for categorical variables, followed by Tukey's post-hoc test at the significance level of 95%.

RESULTS

The flow, setting time, and radiopacity of all tested CSBSs satisfied the ISO 6876/2012 standards. Further, these CSBS showed shrinkage after immersion in distilled water for 30 days and complied with the ISO 6876/2001 requirements. The pH of AHB, ESB, TTB, and BIC was greater than 11 whereas AHP had a pH of 6.69 after 4 weeks. CSBS showed excellent biocompatibility compared with that of AHP (P < .05). CLSM showed that alive hPDLFs were attached well to all the tested CSBS but not to AHP.

CONCLUSIONS

CSBS have similar physical characteristics within the ISO standards and higher biocompatibility than epoxy resin-based sealers.

The Use of Premixed Calcium Silicate Bioceramic Sealer with Warm Carrier-Based Technique: A 2-Year Study for Patients Treated in a Master Program

Background: Recently several calcium silicate flowable sealers have been introduced as endodontic materials for the root canal. This clinical study tested the use of a new premixed calcium silicate bioceramic sealer in association with the Thermafil warm carrier-based technique (TF). Epoxy-resin-based sealer with the warm carrier-based technique was the control group. Methodology: Healthy consecutive patients (n = 85) requiring 94 root canal treatments were enrolled in this study and assigned to one filling group (Ceraseal-TF n = 47, AH Plus-TF n = 47) in accordance with operator training and best clinical practice. Periapical X-rays were taken preoperatively, after root canal filling and after 6, 12 and 24 months. Two evaluators blindly assessed the periapical index (PAI) and sealer extrusion in the groups (k = 0.90). Healing rate and survival rate were also evaluated. Chi-square tests was used to analyze significant differences between the groups. Multilevel analysis was performed to evaluate the factors associated with healing status. Results: A total of 89 root canal treatments in 82 patients were analyzed at the end-line (24 months). The total drop-out was 3.6% (3 patients; 5 teeth). A total of 91.1% of healed teeth (PAI 1-2) was observed in Ceraseal-TF, with 88.6% in AH Plus-TF. No significant difference was observed on healing outcome and survival among the two filling groups (p > 0.05). Apical extrusion of the sealers occurred in 17 cases (19.0%). Of these, 6 occurred in Ceraseal-TF (13.3%) and 11 in AH Plus-TF (25.0%). Three Ceraseal extrusions were radiographically undetectable after 24 months. All the AH Plus extrusions did not change during the evaluation time. Conclusions: The combined use of the carrier-based technique and premixed CaSi-based bioceramic sealer showed clinical results comparable with carrier-based technique and epoxy-resin-based sealer. The radiographical disappearance of apically extruded Ceraseal is a possible event in the first 24 months.

Effect of Different Sealers on the Cytocompatibility and Osteogenic Potential of Human Periodontal Ligament Stem Cells: An In Vitro Study

Background: There is tendency for unavoidable sealer extrusion in some clinical cases. This might adversely affect host stem cells and affect healing. This study aimed to investigate the effect of different sealers on the cytocompatibility and osteogenic potential of human periodontal ligament stem cells (hPDLSCs). Methods: The cytotoxic effect of the extracted elutes of VDW.1Seal (VDW.1), Endosequence BC Sealer HiFlow (ES), GuttaFlow-2 (GF), and ADSeal (AD-S) on the hPDLSCs was determined using the MTT assay. Cell proliferation and migration were assessed by the scratch wound healing assay. Osteogenic differentiation potential was assessed. Measurement of pH values and calcium ions release was performed. Results: GF had a significantly higher percentage of viable cells. The cell migration assay showed that GF demonstrated the lowest open wound area percentage. GF and AD-S showed the highest calcium nodule deposition. GF demonstrated higher ALP activity than ES. Expression of RUNX2 and OC genes was similar for all sealers, while OPG gene expression was significantly higher for VDW.1 and GF. ES and AD-S displayed the highest pH values on day 1. Calcium ion release of ES and VDW.1 was significantly the highest. Conclusions: GuttaFlow-2 and VDW.1Seal sealers have favorable behavior toward host stem cells.

Biomimetic Approaches in Clinical Endodontics

In the last few decades, biomimetic concepts have been widely adopted in various biomedical fields, including clinical dentistry. Endodontics is an important sub-branch of dentistry which deals with the different conditions of pulp to prevent tooth loss. Traditionally, common procedures, namely pulp capping, root canal treatment, apexification, and apexigonesis, have been considered for the treatment of different pulp conditions using selected materials. However, clinically to regenerate dental pulp, tissue engineering has been advocated as a feasible approach. Currently, new trends are emerging in terms of regenerative endodontics which have led to the replacement of diseased and non-vital teeth into the functional and healthy dentine-pulp complex. Root- canal therapy is the standard management option when dental pulp is damaged irreversibly. This treatment modality involves soft-tissue removal and then filling that gap through the obturation technique with a synthetic material. The formation of tubular dentine and pulp-like tissue formation occurs when stem cells are transplanted into the root canal with an appropriate scaffold material. To sum up tissue engineering approach includes three components: (1) scaffold, (2) differentiation, growth, and factors, and (3) the recruitment of stem cells within the pulp or from the periapical region. The aim of this paper is to thoroughly review and discuss various pulp-regenerative approaches and materials used in regenerative endodontics which may highlight the current trends and future research prospects in this particular area.

The Effect of Bioceramic HiFlow and EndoSequence Bioceramic Sealers on Increasing the Fracture Resistance of Endodontically Treated Teeth: An In Vitro Study

Background/purpose Root fractures after endodontic treatment are a serious complication, and it often causes tooth loss, several studies have found a correlation between root canal preparation and filling, and the possibility of root fracture. Therefore, this study aimed to evaluate the root fracture resistance of the endodontically treated mandibular premolars after preparing and filling by EndoSequence Bioceramic (BC), EndoSequence BC HiFlow, and AH Plus (AHP). Materials and methods The study sample consisted of 75 single-rooted and single-canal mandibular premolars, they were randomly distributed into five groups: Group I: root canals preparation and fillings with AHP sealer; Group II: root canals preparation and fillings with EndoSequence BC sealer; Group III: root canals preparation and fillings with BC HiFlow sealer; Group IV (Negative Control): without root canals preparation; and Group V (Positive Control): canals preparation without root canals filling. A glide path was established by #10 hand K-file, then the crowns were cut, and the canals were prepared and filled. All teeth were restored with glass ionomer cement and kept in an incubator at 37°C for a week. All samples were placed within acrylic bases and a vertical force was applied using a Testometric machine and the fracture resistance force was recorded. Results EndoSequence BC and BC HiFlow groups showed slightly better fracture resistance (494.440, 496.960 N respectively) than AHP group (492.680 N). However, no statistically significant difference was found between the two groups (P-value >0.05). The greatest mean fracture force was observed in the positive control group (736.040 N) with statistically significant difference between the other groups (P-value <0.01) and the least mean fracture force was shown in the negative control group (318.040 N) with statistically significant difference between the other groups (P-value <0.01). Conclusion Based on this in vitro study, the use of EndoSequence BC, BC HiFlow, and AHP enhanced the fracture resistance in root-filled single-rooted premolar teeth. While, the application of EndoSequence BC, BC HiFlow, and AHP did not increase the fracture resistance of roots compared to that of unprepared root canals.

Bioactivity Potential of Bioceramic-Based Root Canal Sealers: A Scoping Review

INTRODUCTION

Bioceramic-based root canal sealers are novel materials with a bioactivity potential that stands out compared with conventional root canal sealers. However, the term bioactivity may be overused and is often misunderstood. Hence, the objective of this study was to synthesize and map key concepts related to the bioactivity analysis of bioceramic-based root canal sealers.

METHODS

The present scoping review is reported in accordance with the PRISMA-ScR Statement and is registered in the Open Science Framework. Two blinded reviewers carried out a comprehensive search in six databases up to January 10th, 2022: MEDLINE, Scopus, Embase, Web of Science, Cochrane Library, and Lilacs/BBO. Eligibility was considered for in vitro and in vivo studies that evaluated the bioactivity potential of bioceramic-based root canal sealers.

RESULTS

A total of 53 studies were included in the qualitative synthesis. In vitro bioactivity was evaluated through the mineralization potential, formation of carbonated apatite on the surface, and the gene expression related to proteins involved in the mineralization process. Meanwhile, for in vivo studies, staining techniques associated with immunohistochemical tests were mainly used to detect mineralization on the material-host tissue interface.

CONCLUSIONS

According to the methodology used, the most prevalent methods to assess bioactivity in acellular form were the immersion of the material in Hank's balanced salt solution, followed by surface observation with scanning electron microscopy and energy dispersive X-ray. In cell cultures, the chosen method was usually Alizarin Red staining, followed by the evaluation of alkaline phosphatase enzymatic activity and the use of molecular biology tests.

Are Endodontic Solvents Cytotoxic? An In Vitro Study on Human Periodontal Ligament Stem Cells

The aim of this study was to assess the influence of eucalyptol, chloroform, and Endosolv on the proliferative capability, cell viability, and migration rates of human periodontal ligament stem cells (hPDLSCs) in vitro. Solvent eluates were formulated following ISO 10993-5 guidelines, and 1%, 0.25%, and 0.1% dilutions were prepared. The HPDLSCs were isolated from the extracted third molars of healthy donors. The following parameters were assessed: cell viability via trypan blue and IC50 assays, cell migration via horizontal wound healing assay, cell morphology via cell cytoskeleton staining (phalloidin labeling), and cell oxidative stress via reactive oxygen species assay. The data were analyzed using one-way ANOVA and Tukey’s posthoc tests, and their significance was established at p < 0.05. Chloroform and eucalyptol exhibited significantly higher cytotoxicity on the hPDLSCs in vitro compared to the control group, as shown by the cell viability, migration, morphology, and reactive oxygen species release assays. Alternatively, Endosolv showed adequate cytotoxicity levels comparable to those of the control group. The cytotoxicity of the tested endodontic solvents increased in a dose-dependent manner. The results from the present study highlight the cytotoxicity of chloroform and eucalyptol. Thus, their limited and cautious use is recommended, avoiding solvent extrusion.

In Vitro Cytotoxicity and Mineralization Potential of an Endodontic Bioceramic Material

OBJECTIVE

 The interest in bioceramic materials has been steadily growing for different applications in endodontics. With the continued introduction of new bioceramic-based materials into the market, it is of great importance to assess the biocompatibility before providing recommendations on their clinical use. This study evaluated the in vitro cytotoxicity and mineralization potential of two consistencies of unset premixed bioceramic material (TotalFill BC RRM putty and TotalFill BC sealer) compared with an epoxy resin-based sealer (AH Plus) on osteoblast cells.

MATERIALS AND METHODS

 Overall, 100% extracts were obtained by weighing 0.1 g of each material in 1 mL of cell culture media. Primary human osteoblast (HOB) cells (n = 4) were treated with different concentrations (100, 50, 25, 12.50, and 6.25%) of each extract. XTT assay and Alizarin Red S staining were used to evaluate the cytotoxic effect and the biomineralization potential, respectively.

STATISTICAL ANALYSIS

 Data were analyzed by one-way analysis of variance followed by Tukey's post hoc tests.

RESULTS

 The cytotoxicity assay after 24 h treatment showed that all materials at high concentrations of the extract (100 and 50%) were toxic to HOB (p < 0.001). On the contrary to TotalFill BC RRM Putty, AH Plus and TotalFill BC sealer were toxic at 25% concentration. However, at 12.5% concentration and lower, all materials were nontoxic. The mineralization potential analyzed after 7 and 14 days showed that TotalFill BC material-treated cells could deposit mineralized nodules in the normal and osteogenic medium unlike AH plus-treated cells.

CONCLUSION

 At low concentrations, TotalFill BC materials showed higher biocompatibility to HOB cells than AH Plus, enhanced the viability of the cells, maintained their typical morphology, and induced the formation of mineralized nodules. Despite the encouraging data, clinical trials are needed to identify the effect of this material on the long-term outcome of endodontic treatment.

Physico-chemical properties of calcium silicate-based sealers in powder/liquid and ready-to-use forms

Calcium silicate-based root canal sealers have been developed in powder/liquid or premixed ready-to-use forms. The evaluation of the physico-chemical properties of a prototype powder/liquid MTApex Sealer (Ultradent) in comparison to a ready-to-use material EndoSequence BC Sealer (Brasseler) was performed. The paste/paste epoxy resin-based AH Plus (Dentsply) served as control for comparisons. The sealers were evaluated (n = 6) regarding setting time (in dry and moist environments), flow and radiopacity, following the ISO-6876/2012 standard. Also, the pH was assessed. Material's surface and chemical characterization was evaluated using scanning-electron-microscopy (SEM) and energy-dispersive-spectrometry (EDS). Mixed ANOVA, Shapiro-Wilk, Levene, and post-hoc analysis with Bonferroni correction were performed at a significance level of 5%. MTApex Sealer exhibited the highest flow and EndoSequence BC Sealer had a significantly longer setting time in dry compared to the moist environment; however, for MTApex Sealer and AH Plus no significant changes occurred when additional moisture was provided. All materials exceeded 7 mm Al of radiopacity and showed a decreasing alkalinity over the 21 day-analysis. SEM/EDS evaluation resulted in peaks of calcium, silicon, and the respective radiopacifier. The prototype powder/liquid MTApex Sealer had the highest flow and similar setting time in both dry and moist environments; opposingly, EndoSequence BC Sealer was crucially influenced by external moisture. This suggests that the powder/liquid materials' setting seems to be more predictable.

Intratubular penetration capacity of HiFlow bioceramic sealer used with warm obturation techniques and single cone: A confocal laser scanning microscopic study

Objective

The aim of this paper was to evaluate the intratubular penetration area of a bioceramic sealer, using continuous wave (CW), vertical condensation (VC) with two different types of gutta-percha (conventional (NG) and bioceramic-coated (BG)) and single cone (SC) technique with BG gutta-percha, in different root thirds.

Methods

A total of 150 mature single-root human teeth (including incisors, canines and premolars) were prepared and randomly divided into five groups (n = 30). Teeth were filled using a bioceramic sealer (TotalFill BC Sealer HiFlow ®) and two different types of gutta-percha, with CW and VC techniques, the teeth in the control group were filled with SC technique and BG gutta-percha. The teeth were sectioned and evaluated as one-third portions in each case under a confocal laser microscope. The penetration area measurements were carried out with the Autocad ® programme. Data was analyzed using the one-factor ANOVA test (p < 0.05) and Post Hoc Test (p < 0.05).

Results

The ANOVA Test showed significant differences in the penetration areas of the five obturation techniques (P < 0.05). The Post Hoc Test exhibited significant differences in multiple comparisons (P < 0.05). There was more dentinal tubule penetration in the coronal third than in the apical third in all techniques.

Conclusions

The intratubular penetration of the bioceramic sealer was influenced by the obturation techniques tested, but not by the different gutta-percha tested. There was more penetration of sealer in the warm obturation techniques than the SC, regardless of the type of gutta-percha used.

Dentin Sealing of Calcium Silicate-Based Sealers in Root Canal Retreatment: A Confocal Laser Microscopy Study

The aim of the present in vitro study was to evaluate the intratubular penetration of three bioceramic sealers in root canal retreatment. Here, 30 single-rooted human teeth were instrumented with the Protaper Universal system and filled with gutta-percha and the epoxy-resin-based sealer AH Plus mixed with rhodamine B. After two weeks in a humid environment, they were re-instrumented with Reciproc Blue and divided into three groups according to the endodontic sealer to be used in the re-filling (n = 10): G1: CeraSeal, G2: TotalFill BC Sealer, G3: TotalFill BC Sealer HiFlow. For the filling, a single cone technique was used, and the respective sealers were mixed with fluorescein. The roots were then sectioned at 2, 5, and 8 mm (apical, medial, and coronal measurement points, respectively) from the apex, and the dentinal tubule penetration depth and percentage of penetration around the canal perimeter were evaluated by means of confocal laser scanning microscopy (CLSM). Penetration between groups was compared using the Kruskal−Wallis test, and within each group using the Wilcoxon test. Statistical significance was established at p < 0.05. A non-significant reduction was found in the penetration depths and in a percentage of penetration around the canal perimeter between AH Plus and the tested calcium-silicate-based sealers (p > 0.05). Consequently, this reduction may not affect the three-dimensional seal of the root canal system in a negative manner. The penetration depth and percentage of penetration around the canal perimeter at both the root canal treatment and retreatment were significantly reduced from the coronal to apical points in all groups (p < 0.05).

Cytocompatibility and bioactive potential of AH Plus Bioceramic Sealer: an in vitro study

Aim

To assess the cytocompatibility and bioactive potential of the new calcium silicate cement‐based sealer AH Plus Bioceramic Sealer (AHPbcs) on human periodontal ligament stem cells (hPDLSCs) compared with the epoxy resin‐based sealer AH Plus (AHP) and the calcium silicate cement‐based sealer Endosequence BC Sealer (ESbcs).

Methodology

Standardized sample discs and 1:1, 1:2 and 1:4 eluates of the tested materials were prepared. The following assays were performed: surface element distribution via SEM–EDX, cell attachment and morphology via SEM, cell viability via a MTT assay, cell migration/proliferation via a wound‐healing assay, osteo/cemento/odontogenic marker expression via RT‐qPCR and cell mineralized nodule formation via Alizarin Red S staining. HPDLSCs were isolated from extracted third molars. Comparisons were made with hPDLSCs cultured in unconditioned (negative control) or osteogenic (positive control) culture media. Statistical significance was established at p < .05.

Results

A higher peak of Ca²+ was detected from ESbcs compared with AHPbcs and AHP in SEM–EDX. Both AHPbcs and ESbcs showed significantly positive results in the cytocompatibility assays (cell viability, migration/proliferation, attachment and morphology) compared with a negative control group, whilst AHP showed significant negative results. Both AHPbcs and ESbcs exhibited an upregulation of at least one osteo/odonto/cementogenic marker compared with the negative and positive control groups. Both ESbcs and AHPbcs showed a significantly higher calcified nodule formation than the negative and positive control groups, indicative of their biomineralization potential and were also significantly higher than AHP group.

Conclusion

AH Plus Bioceramic Sealer exhibited a significantly higher cytocompatibility and bioactive potential than AH Plus and a similar cytocompatibility to that of Endosequence BC Sealer. Endosequence BC Sealer exhibited a significantly higher mineralization potential than the other tested sealers. The results from this in vitro study act as supporting evidence for the use of AH Plus Bioceramic Sealer in root canal treatment.

Physicochemical properties and osteoclastogenesis for three premixed calcium silicate-based sealers post set

Solubility, pH, ion release, cytotoxicity, and osteoclastogenesis inhibition in bone marrow-derived monocyte macrophages (BMMs) were evaluated in EndoSequence BC Sealer (END), Bio-C Sealer (BC), and Sealer Plus BC (SPBC). pH was determined after immersion of the sealers in deionized water (DW) and Minimum Essential Medium Alpha (α-MEM). Solubility was obtained by mass loss. Ion release was measured by using X-ray fluorescence spectroscopy (XRF). Cytotoxicity was evaluated by MTT assay. Inhibition of osteoclastogenesis was evaluated by tartrate-resistant acid phosphatase (TRAP). Data were analyzed using the t-test, ANOVA and Tukey/Dunnett's post-hoc tests (α = 0.05). END had the highest pH in DW (p < 0.05), and BC, in α-MEM (p < 0.05). Solubility in DW was the lowest for SPBC (p < 0.005). The highest calcium release was observed for BC in DW at 12 h (p < 0.05), and in α-MEM at 12 and 24 h (p < 0.05). The lowest toxicity was detected for END (p < 0.05). BC had the highest inhibitory effect on osteoclasts (p < 0.05). Overall, the highest solubility and pH values were found in DW. However, the calcium silicate-based sealer showed higher solubility than the ISO standards. Calcium release was the highest for BC. END showed the highest cell viability, and BC, the highest osteoclast inhibition.

Biocompatibility of a New Calcium Silicate-Based Root Canal Sealer Mediated via the Modulation of Macrophage Polarization in a Rat Model

(1) Background: The EndoSequence BC Sealer HiFlow (Brasseler, Savannah, GA, USA) has recently been introduced in clinical applications. Thus, the aims of the present study are to determine its biocompatibility in vivo and to examine its ability to drive macrophage polarization in vitro and in vivo. (2) Methods: HiFlow was implanted into rat connective tissue for 7, 30 and 150 days. The microstructures and elemental compositions were determined by scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX). Hematoxylin–eosin, immunofluorescence, RT–qPCR and flow cytometry were used to elucidate the effects on inflammatory responses and macrophage polarization. (3) Results: SEM-EDX revealed the formation of surface hydroxyapatite crystal layers. Histological evaluation showed that HiFlow exhibited long-term biocompatibility because it decreased inflammatory responses and reduced the number of macrophages over time; however, tissue necrosis was observed in all the groups. RT–qPCR verified that HiFlow regulated the expression of inflammatory factors to inhibit the inflammatory response. Immunofluorescence analysis performed on in vivo samples revealed that HiFlow promoted M2-like macrophage polarization, and these results were confirmed by flow cytometry in vitro. (4) Conclusion: After 150 days of investigation, HiFlow was considered biologically acceptable, and the formation of apatite crystal layers and the promotion of M2-like macrophage polarization may contribute to its favorable biocompatibility.

Tracing the toxic ions of an endodontic tricalcium silicate-based sealer in local tissues and body organs

BACKGROUND

This study aimed to track the toxic ions released by MTA Fillapex, BioRoot RCS, and an experimental tricalcium silicate-based sealer (CEO) into local and distant tissues as well as to investigate their potential adverse effects. In addition, the chemical constituents of the sealers were also evaluated. The main components of the dry powders, pastes, and mixed sealers were characterized.

MATERIAL AND METHODS

Dry powder and sealer discs were each set for 72 h and their main components were characterized by energy dispersive X-ray spectroscopy. Polyethylene tubes filled with sealers were used to measure silicon and calcium ions. Polyethylene tubes filled with sealers or empty tubes were implanted into the dorsal connective tissue of Wistar rats. On days 7, 15, 30, and 45, the animals were euthanized and their brains, livers, kidneys, and subcutaneous tissues were removed and processed to determine the concentrations of chromium, cobalt, copper, lead, iron, magnesium and nickel using an inductively coupled plasma optical emission spectrometer.

RESULTS

The main compounds in all sealers were carbon, oxygen, silicon, and calcium. MTA Fillapex release more Si while highest levels of Si were found in presence of BioRoot. The release of Si and Ca ions promoted by MTA Fillapex raise by time. No traces of cobalt, chromium, or magnesium were detected in any tissue. Irrespective of the sealer, no traces of copper and lead were found in the subcutaneous tissue; however, they were observed in the organs. The highest concentration of iron was identified in the liver. All sealers exhibited similar nickel traces in the brain, kidney, and liver except for MTA Fillapex, which demonstrated levels higher than CEO in the subcutaneous tissue on day 7. Tracing nickel ions over time revealed that lowest concentrations were found in subcutaneous tissue.

CONCLUSION

Taken together, our data demonstrate that CEOs have chemical compositions similar to those of other commercial sealers. Furthermore, none of them exhibited a threat to systemic health. Moreover, the minimal amounts of iron and nickel detected were not related to the sealers.

Evaluation of the Physicochemical and Biological Properties of EndoSequence BC Sealer HiFlow

INTRODUCTION

Understanding the physicochemical and biological properties of endodontic sealers is important for endodontic treatment planning. This study evaluated the properties of EndoSequence BC Sealer HiFlow (BCH; Brasseler USA, Savannah, GA), EndoSequence BC Sealer (BC, Brasseler USA), and AH Plus (AHP; Dentsply DeTrey, Konstanz, Germany). The effect of temperature on the setting time and flow of these sealers was also evaluated.

METHODS

The setting time, flow, radiopacity, pH, solubility, and calcium release were investigated following ISO guidelines. The morphology and chemical composition of the sealers were evaluated by scanning electron microscopy and energy-dispersive spectroscopy. The antibacterial activity of sealers was tested against 2 strains of Enterococcus faecalis. Sealer cytotoxicity and the effects on messenger RNA expression of proinflammatory and mineralization genes were also investigated. Data analysis was performed using analysis of variance, Tukey, Kruskal-Wallis, and Dunn multiple comparison tests. P ≤ .05 was considered statistically significant.

RESULTS

The setting time and flow rate of all sealers were affected by heat (P ≤ .05). The setting times and solubility of BCH and BC were significantly higher than AHP (P ≤ .0001). The radiopacity of AHP was higher than BCH and BC (P ≤ .0001). All sealers were alkaline and had antibacterial effects. Cell viability was higher for BCH and BC than AHP (P ≤ .0001). No significant differences in messenger RNA expression of proinflammatory and mineralization genes were observed.

CONCLUSIONS

Overall, BCH and BC had similar physicochemical and biological properties. The observed high solubility of BCH and BC as well as the high cytotoxicity of AHP might negatively impact the clinical performance of these materials. The application of heat affected the setting time and flow of all sealers.

Biological interactions between calcium silicate-based endodontic biomaterials and periodontal ligament stem cells: A systematic review of in vitro studies

BACKGROUND

Most recently, the biological interactions, that is cytocompatibility, cell differentiation and mineralization potential, between calcium silicate-based biomaterials and periodontal ligament stem cells (PDLSCs) have been studied at an in vitro level, in order to predict their clinical behaviour during endodontic procedures involving direct contact with periodontal tissues, namely root canal treatment, endodontic surgery and regenerative endodontic treatment.

OBJECTIVE

The aim of the present systematic review was to present a qualitative synthesis of available in vitro studies assessing the biological interaction of PDLSCs and calcium silicate-based biomaterials.

METHODOLOGY

The present review followed PRISMA 2020 guidelines. An advanced database search was performed in Medline, Scopus, Embase, Web of Science and SciELO on 1 July 2020 and last updated on 22 April 2021. Studies assessing the biological interactions of PDLSCs with calcium silicate-based sealers (CSSs) and/or cements (CSCs) at an in vitro level were considered for inclusion. The evaluation of the 'biological interaction' was defined as any assay or test on the cytotoxicity, cytocompatibility, cell plasticity or differentiation potential, and bioactive properties of PDLSCs cultured in CSC or CSS-conditioned media. Quality (risk of bias) was assessed using a modified CONSORT checklist for in vitro studies of dental materials.

RESULTS

A total of 20 studies were included for the qualitative synthesis. CSCs and CSSs, as a group of endodontic materials, exhibit adequate cytocompatibility and favour the osteo/cementogenic differentiation and mineralization potential of PDLSCs, as evidenced from the in vitro studies included in the present systematic review.

DISCUSSION

The influence of the compositional differences, inclusion of additives, sample preparation, and varying conditions and manipulations on the biological properties of calcium silicate-based materials remain a subject for future research.

CONCLUSIONS

Within the limitations of the in vitro nature of the included studies, this work supports the potential use of calcium silicate-based endodontic materials in stem cell therapy and biologically based regenerative endodontic procedures.

REGISTRATION

OSF Registries; https://doi.org/10.17605/OSF.IO/SQ9UY.

Calcium Silicate-Based Root Canal Sealers: A Narrative Review and Clinical Perspectives

Over the last two decades, calcium silicate-based materials have grown in popularity. As root canal sealers, these formulations have been extensively investigated and compared with conventional sealers, such as zinc oxide-eugenol and epoxy resin-based sealers, in in vitro studies that showed their promising properties, especially their biocompatibility, antimicrobial properties, and certain bioactivity. However, the consequence of their higher solubility is a matter of debate and still needs to be clarified, because it may affect their long-term sealing ability. Unlike conventional sealers, those sealers are hydraulic, and their setting is conditioned by the presence of humidity. Current evidence reveals that the properties of calcium silicate-based sealers vary depending on their formulation. To date, only a few short-term investigations addressed the clinical outcome of calcium silicate-based root canal sealers. Their use has been showed to be mainly based on practitioners' clinical habits rather than manufacturers' recommendations or available evidence. However, their particular behavior implies modifications of the clinical protocol used for conventional sealers. This narrative review aimed to discuss the properties of calcium silicate-based sealers and their clinical implications, and to propose rational indications for these sealers based on the current knowledge.

Topical fluoride varnishes promote several biological responses on human gingival cells

OBJECTIVE

To compare the in vitro cytotoxicity of four commercial topical fluoride varnishes widely used in daily dental practice for the prevention of caries on human fibroblasts: Cervitec F, Fixofluor, Fluor Protector S and Duraphat.

MATERIAL AND METHODS

Human gingival fibroblasts (hGF) were exposed to different concentrations of fluoride varnishes extracts. Biological assays, including MTT and IC50 value determination, annexin-V/7-AAD staining, cell migration and F-actin staining with phalloidin were carried out. Statistical analyses were performed using one-way ANOVA and Tukey's post hoc test.

RESULTS

At 4% concentration, all of the fluoride varnishes extracts affected fibroblasts metabolic activity, exhibiting a high degree of cytotoxicity at all measured time points. At 0.1% and 1%, Duraphat and Fixofluor or Fluor Protector S and Cervitec F exerted the lowest or highest cytotoxic effects, respectively. Similar effects were evidenced when induction of apoptosis/necrosis and cell migration assays were analyzed. Immunocytochemical assays revealed a similar number of fibroblasts, without changes in the morphology and F-actin content at 0.1% concentration of all tested materials, while at 1% concentration, Fluor Protector S and Cervitec F showed few cells with aberrant morphology or non-adhered cells, respectively.

CONCLUSIONS

Different commercial topical fluoride varnishes with the same therapeutic indication may exhibit different biological effects and cytotoxicity on fibroblasts.

A comparative study of dentinal tubule penetration and the retreatability of EndoSequence BC Sealer HiFlow, iRoot SP, and AH Plus with different obturation techniques

Objectives

This study aimed to evaluate dentinal tubule penetration and the retreatability of EndoSequence BC Sealer HiFlow (HiFlow), iRoot SP, and AH Plus when using the single-cone (SC) or continuous wave condensation (CWC) technique.

Materials and methods

Sixty-five single-rooted teeth were instrumented and randomly divided into 5 groups: group 1, AH Plus/CWC; group 2, iRoot SP/CWC; group 3, iRoot SP/SC; group 4, HiFlow/CWC; and group 5, HiFlow/SC. The ability to re-establish patency during endodontic retreatment was recorded, as was the time taken to reach the working length. Dentinal tubule penetration and remaining debris after retreatment were evaluated by confocal microscopy and scanning electron microscopy. Data were analyzed by Kruskal-Wallis test and Dunn’s multiple comparisons test (α = 0.05).

Results

The HiFlow/CWC and iRoot SP/CWC groups required more time to reach the working length than groups that underwent the SC technique regardless of the sealer used (P < .05). The HiFlow/CWC group showed a significantly higher percentage of sealer penetration area than that of the iRoot SP/SC at 4 mm from the apex (P < .05) and penetrated deeper into dentinal tubules than iRoot SP/SC at both 8-mm and 12-mm levels (P < .05). Moreover, the HiFlow/CWC and HiFlow/SC groups demonstrated less remaining sealer along the canal wall than AH Plus/CWC group at 4-mm level (P < .05).

Conclusions

HiFlow/CWC technique showed better performance in dentinal tubule penetration than that of iRoot SP/SC. Both HiFlow and iRoot SP combined with CWC technique groups required more retreatment time than the other groups. Furthermore, using HiFlow with either the CWC or SC technique left less remaining sealer at 4-mm level than using AH Plus with the CWC technique during retreatment.

Clinical relevance

With favorable performance in dentinal tubule penetration and retreatability in endodontic retreatment, the combined use of EndoSequence BC Sealer HiFlow with the recommended continuous wave condensation technique may be a worthwhile choice in root canal treatment.

Physico-Chemical Investigation of Endodontic Sealers Exposed to Simulated Intracanal Heat Application: Hydraulic Calcium Silicate-Based Sealers

The aim of this study was to gain information about the effect of thermal treatment of calcium silicate-based sealers. BioRoot RCS (BR), Total Fill BC Sealer (TFBC), and Total Fill BC Sealer HiFlow (TFHF) were exposed to thermal treatment at 37 °C, 47 °C, 57 °C, 67 °C, 77 °C, 87 °C and 97 °C for 30 s. Heat treatment at 97 °C was performed for 60 and 180 s to simulate inappropriate application of warm obturation techniques. Thereafter, specimens were cooled to 37 °C and physical properties (setting time/flow/film thickness according to ISO 6876) were evaluated. Chemical properties (Fourier-transform infrared spectroscopy) were assessed after incubation of the specimens in an incubator at 37 °C and 100% humidity for 8 weeks. Statistical analysis of physical properties was performed using the Kruskal-Wallis-Test (P = 0.05). The setting time, flow, and film thickness of TFBC and TFHF were not relevantly influenced by thermal treatment. Setting time of BR decreased slightly when temperature of heat application increased from 37 °C to 77 °C (P < 0.05). Further heat treatment of BR above 77 °C led to an immediate setting. FT-IR spectroscopy did not reveal any chemical changes for either sealers. Thermal treatment did not lead to any substantial chemical changes at all temperature levels, while physical properties of BR were compromised by heating. TFBC and TFHF can be considered suitable for warm obturation techniques.

Synthesis, Characterization, and Antibacterial Evaluation of a Cost-Effective Endodontic Sealer Based on Tricalcium Silicate-White Portland Cement

Mineral trioxide aggregate (MTA) is an ideal yet costly endodontic sealer material. Tricalcium silicate-white Portland cement (TS-WPC) seems to have similar characteristics to those of MTA. This work aims to characterize a modified TS-WPC and evaluate its antibacterial properties as a potential endodontic sealer material. The modified TS-WPC was synthesized from a 4:1 mixture of sterilized Indocement TS-WPC and bismuth trioxide using a simple solution method with 99.9% isopropanol. The mixture was stirred until it was homogenous, centrifuged, and dried. The material was then characterized using infrared spectroscopy, X-ray diffraction, and electron microscopy and subjected to antibacterial evaluation against Enterococcus faecalis using a Mueller-Hinton agar inhibition test. The results showed that the material was characterized by main functional groups of hydroxyls, silicate, bismuth trioxide, and tricalcium silicate, like those of a commercial MTA-based sealer, both tested after hydration. Modified TS-WPC before hydration showed similar powder morphology and size to the commercial one, indicating the ease of manipulation. Both materials exhibited antibacterial activity due to calcium dihydroxide's ability to absorb carbon dioxide, which is essential for the anaerobic E. faecalis, with minimum inhibitory effect and bactericidal concentrations of 12,500 ppm and 25,000 ppm, respectively. The modified TS-WPC has the potential to become a cost-effective alternative endodontic sealer material.

Subcutaneous Implantation Assessment of New Calcium-Silicate Based Sealer for Warm Obturation

Calcium silicate-based sealers were recently introduced as a new class of endodontic sealers, with potential further benefits due to their bioactivity. The aim of this study was to evaluate the biocompatibility of two new hydraulic calcium silicate-based sealers, TotalFill BC Sealer (FKG, La Chaux-des-Fonds, Switzerland) and TotalFill BC Sealer HiFlow (FKG, La Chaux-des-Fonds, Switzerland) through subcutaneous implantation in connective tissue of rats. Subcutaneous implantation was performed in 16 young Wistar rats. Four polyethylene tubes were implanted in each animal, one empty to serve as a control, and three filled with tested sealers: AH Plus as reference (Dentsply DeTrey, Konstanz, Germany), TotalFill BC Sealer (BC) and TotalFill BC Sealer HiFlow (HiFlow). Eight rats were euthanized at 8 days and the remaining eight at 30 days. Hematoxylin-eosin staining was used to score the inflammatory reaction, macrophage infiltrate and to measure the thickness of the fibrous capsule. von Kossa staining was performed to evaluate the mineralization level. Kruskal-Wallis test followed by Dunn's post hoc test was used to analyze non-parametric data. To analyze the influence of the implantation time within each material, a Mann-Whitney U test was performed. At eight days post-implantation, AH Plus induced a more intense inflammatory reaction when compared both with the control (p ≤ 0.001) and BC (p ≤ 0.01). HiFlow presented a higher score of macrophage infiltrate than control (p ≤ 0.01) and BC (p ≤ 0.05). The fibrous capsule thickness in this period was significantly higher for the BC group when compared to control (p ≤ 0.01) and AH Plus (p ≤ 0.05). The mineralization potential was higher for the HiFlow group when compared with the control (p ≤ 0.001) and AH Plus (p ≤ 0.001). At 30 days post-implantation, the score for the inflammatory reaction remained higher for the AH Plus group when compared both to control (p ≤ 0.01) and BC (p ≤ 0.001). The macrophage infiltrate of the HiFlow was significantly higher than control (p ≤ 0.001) and AH Plus groups (p ≤ 0.01), additionally, the fibrous capsule of the BC (p ≤ 0.001) and HiFlow (p ≤ 0.01) groups were both thicker than control. Mineralization potential was observed only on BC (p ≤ 0.05) and HiFlow groups (p ≤ 0.001), when compared to control). BC exhibited the best biocompatibility performance of all tested sealers and HiFlow provided the greatest induction of mineralized tissues. Both TotalFill BC Sealer and TotalFill BC Sealer HiFlow are biocompatible and show potential bioactivity when implanted in the subcutaneous tissue. Bioactivity was not found in AH Plus.

Analysis of the physicochemical properties, cytotoxicity and volumetric changes of AH Plus, MTA Fillapex and TotalFill BC Sealer

Background

To evaluate the physicochemical properties and cytotoxicity of AH Plus, MTA Fillapex and TotalFill BC Sealer. Volumetric changes were also evaluating using micro-computed tomography (micro-CT).

Material and Methods

Radiopacity and flow were evaluated in accordance with the ISO 6876, while setting time was evaluated in accordance with the ASTM- C266-08 specifications. The release of Ca2+ ions and pH were measured with spectrophotometer and pH meter, respectively, after different time intervals (1h, 3h, 24h, 72h, 168h, and 360h). Cytotoxicity was evaluated by MTT reduction assay to check 3T3 cells viability at 24, 48 and 72 hours. Volumetric change was evaluated by micro-CT, by using 30 acrylic teeth, filled with gutta-percha cones and the tested root canal sealer. The samples were evaluated after 168h, 360h and 720h of immersion in distilled water. Data were statistically analyzed by one-way ANOVA and Tukey test or by Kruskal-Wallis and Dunn tests (P<0.05).

Results

MTA Fillapex and TotalFill BC Sealer showed lower radiopacity than AH Plus (P<0.05). The MTA Fillapex showed the highest flow, while AH Plus showed the lowest flow (P<0.05). The initial and final setting time of AH Plus were lower than MTA Fillapex and TotalFill BC Sealer (P<0.05). In general, TotalFill BC Sealer presented higher Ca2+ ion release and pH than the other tested sealers. TotalFill BC Sealer also showed overall lower cytotoxicity when compared to the other sealers. Volumetric change of AH Plus and TotalFill BC Sealer was lower than MTA Fillapex (P<0.05).

Conclusions

AH Plus, MTA Fillapex and TotalFill BC Sealer showed slight differences in the physicochemical properties and cytotoxicity, but all suitable for an endodontic sealer. However, AH Plus and TotalFill BC Sealer showed low volumetric changes when compared to MTA Fillapex.

Key words:Calcium silicate, cytotoxicity, physicochemical properties, micro computed tomography.

Microstructural composition, ion release, and bioactive potential of new premixed calcium silicate-based endodontic sealers indicated for warm vertical compaction technique

OBJECTIVE

The aim of this study was to evaluate the microstructural composition, ion release, cytocompatibility, and mineralization potential of Bio-C Sealer ION+ (BCI) and EndoSequence BC Sealer HiFlow (BCHiF), compared with AH Plus (AHP), in contact with human periodontal ligament cells (hPDLCs).

MATERIALS AND METHODS

The sealers' ionic composition and release were assessed using energy-dispersive spectroscopy (EDS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. For the biological assays, hPDLCs were isolated from third molars, and sealer extracts were prepared (undiluted, 1:2, and 1:4 ratios). An MTT assay, wound-healing assay, and cell morphology and adhesion analysis were performed. Activity-related gene expression was determined using RT-qPCR, and mineralization potential was assessed using Alizarin Red staining (ARS). Statistical analyses were performed using one-way ANOVA and Tukey's post hoc test (α < 0.05).

RESULTS

The three sealers exhibited variable levels of silicon, calcium, zirconium, and tungsten release and in their composition. Both BCI and BCHiF groups showed positive results in cytocompatibility assays, unlike AHP. The BCHiF group showed an upregulation of CAP (p < 0.01), CEMP1, ALP, and RUNX2 (p < 0.001) compared with the negative control, while the BCI group showed an upregulation of CEMP1 (p < 0.01), CAP, and RUNX2 (p < 0.001). Both groups also exhibited a greater mineralization potential than the negative and positive controls (p < 0.001).

CONCLUSIONS

The calcium silicate-based sealers considered in the present in vitro study exhibited a high calcium ion release, adequate cytocompatibility, upregulated osteo/cementogenic gene expression, and increased mineralized nodule formation in contact with hPDLCs.

CLINICAL RELEVANCE

From a biological perspective, BCI and BCHiF could be clinically suitable for root canal filling.