Search Results (254)

Continued efforts have been made to enhance the antibacterial properties of root canal sealers by adding antimicrobial agents to them. This study aims to investigate the antibacterial effect of 0.15% silver nanoparticles (NAg) and 5% dimethylaminohexadecyl methacrylate (DMAHDM) when added to EndoSequence Bioceramic (BC) sealer against Enterococcus faecalis (E. faecalis) biofilm and their impact on its physical properties (flowability and film thickness). Four root canal sealers were tested for flow and film thickness properties, as well as against antibiofilm of E. faecalis-impregnated dentin discs, as follows: group 1: EndoSequence BC sealer only; group 2: EndoSequence BC sealer + 0.15% NAg; group 3: EndoSequence BC sealer + 5% DMAHDM; and group 4: EndoSequence BC sealer + 0.15% NAg + 5% DMAHDM. The findings show that all groups had flow and film thickness values that were in accordance with the ISO requirements. Combining 0.15% NAg and 5% DMAHDM in EndoSequence significantly reduced colony-forming unit (CFU) counts by approximately 5 logs. The combination of NAg and DMAHDM offers a promising strategy for developing endodontic sealers with improved antimicrobial properties and acceptable physical performance. Full article

This work presents a comprehensive evaluation of the heat-sealability of films developed from chañar brea gum (CBG), a biopolymer with potential for packaging applications. Heat sealability is a critical property in the packaging industry, as it directly determines the integrity and functionality of the final product. The films were prepared by the 10% casting method with the addition of glycerin, and heat sealing was performed at 140 °C using a heat sealer. Heat sealing was performed on 2 cm × 10 cm strips of chañar gum in the horizontal (CBG-H) and vertical (CBG-V) directions. This study employs a joint determination to explore the fundamental properties of the films, including proximate analysis, antioxidant capacity, FTIR, DSC, TGA-DTGA, XRD, mechanical testing, water vapor permeability, sorption, and biodegradability. By integrating the results of all these determinations, this study seeks to evaluate and explain the “intimate relationships”—i.e., the complex interconnections among the molecular structure, composition, thermal behavior, mechanical properties, and barrier properties of channier gum films—and how these fundamental properties dictate and control their heat sealability. The thermal stability of CBG is up to 200 °C, with a melting point of 152.48 °C. The interstrand spacing was very similar at 4.88 nm for CBG and 4.66 nm for CBG-H. The SEM images of the heat seal show rounded shapes on the surface, while in the cross section, it is homogeneous and almost without gaps. The WVP decreased from 1.7 to 0.37 for CBG and CBG-H, respectively. The Young’s modulus decreased from 132 MPa for CBG to 96.5 MPa for CBG-H. The heat sealability is 656 N/m, with a biodegradability of 4 days. This comprehensive approach is crucial for optimizing the sealing process and designing functional and efficient biodegradable packages. Full article

Background and objectives: Post-operative pain (POP) is a common complication after root canal treatment and is influenced by various clinical and patient-related factors. The present study evaluated the incidence and intensity of POP following root canal treatment using a bioceramic sealer performed by operators with different levels of experience. Methods: A total of 115 patients were included in this prospective observational study. Patients were treated by operators with different levels of experience: postgraduate students (PGSs) and endodontic specialists (ESs). Standardized protocols were used in two distinct appointments: an instrumentation visit and an obturation visit. Obturation was performed using the continuous wave condensation technique and Total Fill Hi-Flow BC Sealer (TFHF). POP, mastication discomfort, and sleep disturbance were assessed at 24, 48, and 72 h after the instrumentation and obturation phases using a numeric rating scale (NRS). Results: The results indicate significantly higher POP after the instrumentation phase, compared to the obturation phase (p < 0.001). The pain intensity progressively decreased over time for both phases. No significant differences were observed between the PGS and ES groups regarding POP, mastication discomfort, or sleep disturbance at any time. Sealer extrusion did not significantly impact POP (p > 0.05). Conclusions: This study found that operator experience does not significantly influence POP when a standardized protocol is followed. The use of TFHF with the continuous wave condensation technique was associated with minimal POP. Full article

We propose a wind spectrum–response surface dual-domain coupling method to study the reliability optimization of tall structures under the action of unsteady wind fields. Unlike traditional research, the dual-domain coupling analysis can quickly and accurately capture structural response defects and optimize size. The first parametric modeling technology establishes a high-precision finite element model of the movable boom structure by establishing a dual-domain coupling framework of pulsating wind and structural optimization. Using MATLAB (instructional R2024b version), the pulsating wind is simulated with uncertainty. The pulsating wind speeds at different heights are converted into wind loads acting on the net-sealed movable boom structure. Secondly, the boom structure’s dynamic response analysis and response surface optimization design were carried out. The final results show that the maximum value of displacement of the optimized net sealer boom is reduced by about 8.06%, the maximum value of stress is reduced by about 11.04%, and the stiffness is improved through the stress monitoring of the existing structure. It showed that the wind-resistant capability of the boom studied by this method is enhanced, improving the study’s efficiency. Full article

The aim of this study is to evaluate the apical sealing ability of novel bioceramic-based (BCB) and widely used resin-based (RB) root canal sealers in combination with traditional or bioceramic-coated gutta-percha points. A total of 92 human single-root extracted teeth were endodontically treated and divided into three groups (A, B, and C) of 30 samples based on the endodontic sealer/type of gutta-percha points/obturation method used. One tooth sample was used for the negative and positive controls (each). Group A: BCB sealer BioRoot RCS (Septodont, Saint-Maur-des-Fossés, France)/bioceramic-impregnated gutta-percha TotalFill BC points (FKG Dentaire, La Chaux-de-Fonds, Switzerland)/cold hydraulic single-cone. Group B: BioRoot RCS (Septodont, France)/traditional Protaper Gold Gutta-Percha Points (Dentsply Sirona, Charlotte, NC, USA)/cold hydraulic single-cone. Group C: RB sealer AdSeal (Meta Biomed, Cheongju, Republic of Korea)/traditional Protaper Gold Gutta-Percha Points (Dentsply Sirona, USA)/warm vertical condensation. A dye penetration method was applied, and the length of apicocoronal penetration was measured using a surgical microscope. The data were statistically analyzed to evaluate differences at the 0.05 significance level. A significant difference was found between groups A and C, p = 0.0003, and groups B and C, p = 0.003. The data analysis proved that the BCB sealer using the cold hydraulic single-cone method ensured a substantially better seal than the RB sealer using the warm vertical condensation method. The choice of the type of gutta-percha points (bioceramic-coated or regular) appeared to be unimportant. No statistical significance was found between groups A and B, which indicates that using bioceramic-coated gutta-percha points does not bring any considerable benefit in view of a no-gap root canal obturation. Full article

This study compared the efficacy of different solutions in achieving patency in teeth filled with AH Plus Bioceramic sealer. Eighty-five premolars with a straight canal were prepared. After sealer placement, a master gutta-percha cone was introduced 2 mm short of the working length. The teeth were stored at 37 °C and 100% humidity for five weeks before retreatment. Filling materials were removed up to the gutta-percha cone’s length. The canals were then randomly assigned to groups: G1 (control, no solution), G2 (5.25% NaOCl), G3 (17% EDTA), G4 (10% citric acid), and G5 (10% formic acid). The apical patency was attempted with a 10 K file within a period of 10 min, by a blinded operator. Additionally, sealer samples were immersed in the solutions, followed by scanning electron microscopy analysis. The Kruskal–Wallis test was used for statistical analysis. Patency was achieved in all canals except one in the control and one in the NaOCl groups. No significant differences were found in the time required to achieve patency. Acid solutions had a greater impact on the sealer’s structural integrity, and a decalcifying effect of EDTA and citric acid was registered. Apical patency in straight canals obturated with AH Plus Bioceramic sealer was consistently achieved regardless of the solution used. Full article

Calcium silicate-based sealers (CSBS) vary in chemical composition, which can influence treatment outcomes. Therefore, the study aimed at comparing several commercially available CSBS regarding microstructure and elemental characterization. Four CSBS (AH Plus Bioceramic Sealer, BioRoot RCS, BioRoot Flow, TotalFill BC Sealer) and a control resin-based sealer (AH Plus) were evaluated using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray powder diffraction analysis (XRD). The specimens were analyzed after setting (SEM, EDX, XRD), as well as after 7 (SEM) and 28 days (SEM, EDX) of incubation in Hank’s balanced salt solution. AH Plus exhibited a uniform matrix and small amounts of calcium (Ca), significantly decreasing after incubation. In contrast, CSBSs exhibited crystalline forms on the surface and increased Ca content, significantly increasing after 28 days of incubation. The main crystalline phase for all tested CSBS was zirconium oxide, while for ERBS it was calcium tungstate. In conclusion, the amount of calcium increased on the surface of CSBSs after incubation, which alkalinized the pH, promoting mineralization, apatite formation, and antibacterial potential. Despite this, the formation of a hydroxyapatite layer was not demonstrated, possibly due to the high dissolution potential of CSBSs. Full article

Background: The primary objective of this study was to evaluate the cytotoxic and genotoxic effects of calcium silicate-based sealers (BioRoot RCS and MTA Fillapex) compared to an epoxy-based sealer (AH Plus). Materials and methods: The study was conducted in vitro with the cell lines HepG2 and V79 to evaluate cytotoxicity and genotoxicity using the comet and micronucleus assays. Eluates of the materials were tested at two different concentrations (3 cm²/mL and 0.5 cm²/mL) after an exposure time of 72 h. Data were analyzed using the Mann–Whitney and Kruskal–Wallis tests (p < 0.05). Results: At lower concentrations in both cell lines, MTA Fillapex showed no significant difference in the measured comet assay parameters compared to the negative control (p > 0.05). In addition, it showed significantly lower genotoxic effects compared to AH Plus for all comet assay parameters, concentrations, and cell lines (p ≤ 0.001). BioRoot RCS showed lower primary DNA damage (p ≤ 0.001) than AH Plus, only at higher concentrations and in the HepG2 cell line. Concerning the two tested bioceramic sealers, BioRoot RCS showed higher tail intensity values compared to MTA Fillapex (p < 0.05). In contrast to the results of the comet assay, BioRoot RCS significantly reduced the number of nuclear buds and nucleoplasmic bridges in the HepG2 cell line compared to MTA Fillapex, whereas reduction in the V79 cell line was only observed for nuclear buds (p < 0.05). Both materials increased the number of apoptotic cells compared to the negative control (p < 0.05). In comparison to AH Plus, BioRoot RCS and MTA Fillapex significantly reduced the number of cells with micronuclei and increased the number of cells with undamaged chromatin (p < 0.05). Conclusions: The findings suggest that MTA Fillapex and BioRoot RCS exhibit superior biocompatibility over AH Plus, as evidenced by their lower cytotoxic and genotoxic effects in vitro. These results support the use of calcium silicate-based sealers in clinical practice, highlighting the need for further studies to evaluate their performance in vivo and their implications for patient safety. Full article

Background: Root canal sealers remain in long-term contact with dental tissues, raising concerns about their potential adverse effects. Methods: This study evaluates the physicochemical properties and ion-release profiles of three dental materials: zinc oxide/eugenol-based sealer, zinc phosphate cement (luting agent), and glass-ionomer cement (restorative material) under acidic (pH 4) and neutral (pH 7) conditions over 24 h and 30 days to determine their behavior and bioactivity in vitro. The materials were evaluated for their setting time, consistency, film thickness, solubility, and ion release using atomic emission spectrometry. The influence of pH and exposure time on ion release was analyzed using multiple regression analysis. Results: All tested materials met the ISO standards for their respective categories. The zinc oxide/eugenol and zinc phosphate cements released increased levels of zinc in acidic environments (pH 4), suggesting potential antimicrobial properties. The glass-ionomer cement exhibited higher silicon and strontium release under a neutral pH (pH 7), indicating potential remineralization effects. Silver from the zinc oxide/eugenol material was below the detection limit of the applied method, suggesting minimal ion release under the tested conditions. Maximum zinc release from root canal sealer occurred after 30 days at pH 4 (1.39 ± 0.26 mg), while the highest silicon release from glass-ionomer cement was observed at pH 7 after 30 days (1.03 ± 0.21 mg). Conclusions: Zinc oxide/eugenol materials exhibited increased zinc release under acidic conditions. In contrast, the restorative and luting materials demonstrated distinct ion-release patterns, aligning with their respective intended applications rather than endodontic purposes. Full article

The objective of this study is to analyze bridge deck condition deterioration and evaluate the impact of concrete sealer and salt usage on deck condition and life-cycle cost. To achieve this goal, machine learning models were built to predict the evolution of bridge deck rating. The deck maintenance history shows that the average bridge age at deck overlay and deck replacement is around 25 and 50 years, respectively. Deck overlay can improve deck condition from an average rating of 6.3 to 7.1, and deck replacement can efficiently recover deck condition from an average rating of 5.3 to 8.5. The effect of concrete sealer on bridge deck condition is only observable at the stage before the first overlay, indicating that concrete sealer may not be effective over the long term. More usages of prewet salt and salt brine in anti-icing result in slightly higher deck condition ratings, while more dry salt in deicing presents slightly lower deck condition ratings, indicating the benefits of salt brine over dry salt. When concrete sealer is applied every 2 or 4 years, it can help extend the service life of the bridge deck by around 1~2 years. If concrete sealer is applied every 12 years, a 6% reduction in life cycle cost could be achieved. Full article

The calcium silicate-based sealers currently available on the market have different compositions and formulations, which is why their physical and chemical properties may vary. (1) The aim of the study was to measure the physico-chemical properties of calcium silicate-based sealers and their push-out bond strength to root dentine, comparing two push-out testing protocols. (2) Standardized specimens of EndoSequence BC, BioRoot RCS, MTA Fillapex, and AH Plus (control) were subjected to pH measurements over 28 days. Radiopacity was measured using a CCD sensor, and flexural strength was assessed using a three-point bending setup. Push-out bond strength was measured in coronal, middle, and apical sections of 40 single-root teeth (conventional method), and cylindrical cavities were prepared for all sealers on the same root dentine disks in 11 third molars (disk method). (3) EndoSequence BC exhibited a higher pH than MTA Fillapex and the highest radiopacity (p < 0.05). The highest flexural and push-out bond strengths were found for AH Plus. The push-out bond strength of EndoSequence BC and BioRoot RCS was higher than MTA Fillapex (p < 0.05). The conventional and disk methods exhibited similar push-out bond strength results, but the data were more homogeneously distributed in the disk method. (4) All calcium silicate-based sealers exhibited a higher pH than AH Plus. MTA Fillapex did not meet the ISO standard. Calcium silicate-based sealers showed weaker performance in terms of physical properties compared to AH Plus. Full article

Apical periodontitis is a common inflammatory condition associated with root canal treatment (RCT) failure. The quality of the three-dimensional root canal seal is critical to the success of the treatment. Bioceramic sealants, such as Neosealer Flo, offer biological advantages such as osteoconduction, biocompatibility and sustained calcium ion release, which may improve apical healing. The aim of this study was to compare AH Plus and Neosealer Flo in terms of postoperative pain, extrusion and periapical healing. A single-blind, randomised clinical trial was conducted with 60 patients divided into AH Plus and Neosealer Flo groups. Post-operative pain was assessed using a visual analogue scale (VAS) at 24 and 48 h and at 7 days. Seal quality and periapical healing were assessed at 6 months using the AAE success criteria by clinical and radiographic evaluation. Neosealer Flo resulted in less postoperative pain at 24 h and 7 days compared to AH Plus. Extrusion did not significantly affect pain or correlate with the type of sealer used. Both materials achieved similar periapical healing rates. Neosealer Flo demonstrated advantages in pain reduction, while both sealants showed comparable efficacy. Full article

Bioceramic materials for endodontic treatments have gradually transformed over the years into materials with enhanced biocompatibility and chemical and mechanical properties compared to earlier generations. In endodontics procedures, these materials are used as restorative material in applications such as root-end fillings, pulp capping, perforations repair, and apexification repair procedures. However, they have far from ideal mechanical and handling properties, biocompatibility issues, aesthetic concerns due to tooth discolouration, limited antibacterial activity, and affordability, which are amongst several key limitations. Notably, bioceramic materials are popular due to their biocompatibility, sealing ability, and durability, consequently surpassing traditional materials such as gutta-percha and zinc oxide–eugenol sealers. A lack of recent advancements in the field, combined with nanomaterials, has improved the formulations of these materials to overcome these limitations. The existing literature emphasises the benefits of bioceramics while underreporting their poor mechanical properties, handling difficulties, cost, and various other drawbacks. The key gaps identified in the literature are the insufficient coverage of emerging materials, narrow scope, limited insights into future developments, and underreporting of failures and complications of the existing materials. Consequently, this review aims to highlight the key limitations of various endodontic materials, primarily focusing on calcium silicate, calcium phosphate, and bioactive glass-based materials, which are the most abundantly used materials in dentistry. Based on the literature, bioceramic materials in endodontics have significantly improved over recent years, with different combinations of materials and technology compared to earlier generations while preserving many of their original properties, with some having affordable costs. This review also identified key innovations that could shape the future of endodontic materials, highlighting the ongoing evolution and advancements in endodontic treatments. Full article

Recently, the single-cone hydraulic canal filling technique using bioceramic sealers was found to hinder retreatment due to the mechanical properties of the bioceramic sealers. This study assessed the effectiveness of four nickel–titanium rotary files in removing gutta-percha and bioceramic sealer from molar root canals in vitro. Eighty-eight root canals from extracted molars were instrumented with Vortex Blue rotary files and filled with gutta-percha and bioceramic sealer using a single-cone technique. After 30 days, the filled canals were randomly divided into four groups according to the file used for re-instrumentation: ProTaper Gold (PTG), Endo ReStart (ERS), XP-3D Shaper (XPD), and HyFlex Remover (HFR). This study assessed whether root canal filling material removal and patency were achieved within a 10-min time frame, recording the time required in seconds. The rate of regaining patency and the time required to achieve patency were compared among groups using a generalized linear model. Scanning electron microscopy was used to evaluate the mechanical changes to the files after use. The patency rate of XPD and HFR was significantly higher than PTG. ERS and XPD demonstrated shorter patency times than HFR and significantly shorter patency times than PTG. SEM images revealed a varied range of reverse windings across file groups. PTG and ERS exhibited microcracks and fractured tips, while XPD and HFR did not display these mechanical alterations. The four file systems in this study displayed varying levels of effectiveness in the retreatment of root canals filled with bioceramic sealers. Full article

Background/Objectives: Since biomineralization by calcium silicate-based sealers (CSBSs) was reported, retrieving canal filling materials may be challenging during endodontic retreatment due to their adhesion to dentin. This study aimed to evaluate the possibility of removing residual mineral deposits from two kinds of CSBSs compared to the AH Plus Jet (AHJ). Methods: Root canals of mandibular premolars were prepared, obturated with the sealer-based obturation method using a WOG medium gutta-percha cone and one of the following sealers: AHJ, AH Plus Bioceramic (AHB), and Ceraseal (CER) (n = 12/group). After 3 weeks, endodontic retreatment was conducted with the WOG files, followed by instrumentation with XP-endo Finisher (XPF). Micro-computed tomography scanning was obtained after canal filling, after retreatment with WOG, and after the use of XPF. The percentage of the removed filling volume was calculated. One-way ANOVA with Tukey’s test and a non-parametric test with Bonferroni’s correction were performed. Root canal dentin after retreatment was examined using a scanning electron microscope (SEM). Results: After supplementary instrumentation with XPF, the mean residual filling volumes for the AHJ, AHB, and CER groups were 1.35 mm³, 0.55 mm³, and 0.82 mm³, respectively. The AHJ group showed greater residual volume compared to the AHB group (p < 0.05). The AHB and CER groups demonstrated higher mean percentages of removed filling volume at 94.8%, and 92.5%, respectively, compared to 87.1% for the AHJ group (p < 0.05). More mineral deposits were observed in the CER group with SEM. Conclusions: AHB and CER are retrievable during endodontic retreatment, with CER preferable due to greater mineral deposits in dentinal tubules. Full article