Search Results (251)

Instrument fracture during endodontic treatment significantly compromises treatment outcomes, with sodium hypochlorite (NaOCl) and other irrigants potentially affecting the cyclic fatigue resistance of nickel–titanium (NiTi) rotary files. This systematic review evaluated the impact of endodontic irrigants on NiTi instrument durability. A comprehensive literature search was conducted across PubMed, Scopus, Web of Science, Embase, Cochrane Library, and WorldCat databases through June 2025, following PRISMA guidelines. Studies investigating cyclic fatigue resistance of NiTi rotary instruments exposed to various irrigants were included. Twenty-seven in vitro studies met the inclusion criteria, involving instruments across multiple file systems and irrigant solutions. The review revealed that NaOCl, particularly at concentrations ≥5% and elevated temperatures, significantly reduced cyclic fatigue resistance in most studies, with scanning electron microscopy confirming surface corrosion and microcrack formation. Heat-treated NiTi alloys demonstrated superior fatigue resistance compared to conventional austenitic alloys. Short-term NaOCl exposure (1–5 min) showed minimal impact, while prolonged exposure combined with autoclave sterilization produced cumulative weakening effects. Alternative irrigants such as EDTA and chlorhexidine showed more neutral effects on instrument integrity. These findings suggest that irrigant selection and exposure protocols significantly influence NiTi instrument longevity, with implications for clinical endodontic practice and instrument safety protocols. Full article

The adhesion of endodontic sealers to dentin may be influenced both by the chemical composition of the sealer and the final irrigation protocol. The aim of this study was to examine the push-out bond strength of three differently formulated bioceramic sealers to root canal dentin, after different irrigation protocols. Four cavities were prepared in dentine discs obtained from middle thirds of third molars with fused roots. Discs were randomly divided into three groups (n = 8). Group 1: specimens were immersed in 2.5% NaOCl; group 2: in 2.5% NaOCl followed by 17% EDTA; and group 3: in a solution of 2.5% NaOCl with 9% etidronic acid (HEDP). The cavities on each disk were filled with four tested sealers: AH Plus Bioceramic, Bio C Angelus, BioRoot RCS, and AH Plus (n = 8 per sealer). The push-out bond strength test was performed after 7 days. The data were statistically analyzed using two-way analysis of variance with the Bonferroni post hoc test (α = 0.05). Irrigation with NaOCl resulted in significantly lower bond strength values of the sealers in comparison to NaOCl/EDTA and NaOCl/HEDP groups. In the NaOCl and NaOCl/HEDP groups, BioRoot RCS showed similar push-out bond strength compared to AH Plus and significantly higher compared to Bio-C and AH Plus Bioceramic. In the NaOCl/EDTA group, bioceramic sealers achieved a significantly weaker bond strength compared to AH Plus. The bond strength of BioRoot RCS was significantly higher compared to Bio-C and AH Plus Bioceramic. The irrigation protocols and the chemical composition of the sealers significantly influenced their bond strength to dentin. Epoxy resin-based sealer achieved the strongest bond strength, while within bioceramic sealers, the highest values were obtained for BioRoot RCS and the lowest for AH Plus Bioceramic. Full article

The integration of microstructured current collectors offers a potential pathway to enhance interface properties in solid-state battery architectures. In this work, we investigate the influence of surface morphology on the electrochemical performance of Zn/Na_2.99Ba_0.005OCl/Cu electrodeless pouch cells by fabricating copper thin films on microstructured parylene-C substrates using a combination of colloidal lithography and reactive ion etching. O₂ plasma etching times ranging from 0 to 15 min were used to tune the surface topography, resulting in a systematic increase in root-mean-square roughness and a surface area enhancement of up to ~30% for the longest etching duration, measured via AFM. Kelvin probe force microscopy-analyzed surface potential showed maximum differences of 270 mV between non-etched and 12-minute-etched Cu collectors. The results revealed that the chemical potential is the property that relates the surface of the Cu current collector/electrode with the cell’s ionic transport performance, including the bulk ionic conductivity, while four-point sheet resistance measurements confirmed that the copper layers’ resistivity maintained values close to those of bulk copper (1.96–4.5 µΩ.cm), which are in agreement with electronic mobilities (−6 and −18 cm²V⁻¹s⁻¹). Conversely, the charge carrier concentrations (−1.6 to −2.6 × 10²³ cm⁻³) are indirectly correlated with the performance of the cell, with the samples with lower CCC_bulk (fewer free electrons) performing better and showing higher maximum discharge currents, interfacial capacitance, and first-cycle discharge plateau voltage and capacity. The data were further consolidated with Scanning Electron Microscopy and X-ray Photoelectron Spectroscopy analyses. These results highlight that the correlation between the surface morphology and the cell is not straightforward, with the microstructured current collectors’ surface chemical potential and the charge carriers’ concentration being determinant in the performance of all-solid-state electrodeless sodium battery systems. Full article

Background: Reduced bond strengths in hypmineralised enamel have been reported with increased restorative failures. This study aimed to investigate the shear bond strengths of resin composite to hypomineralised enamel and dentin bonded with two different adhesive systems and pre-treatments. Methods: Thirty-six freshly extracted first permanent molars with MIH and 17 sound third molars were used for shear bond strength tests in enamel and dentin. Specimens of control groups were bonded to resin composite using Scotchbond^TM Universal Plus and Adper^TM Scotchbond 1XT. MIH-affected enamel specimens of six test groups were pre-treated with various chemical agents, such as 35% phosphoric acid, 5% NaOCl, resin infiltration with ICON^®, or a combination of these agents prior to bonding with composite resin using Scotchbond^TM Universal Plus. Bonded specimens were subsequently sheared at a crosshead speed of 1.0 mm/min, after which their fracture modes were recorded. The mean bond strengths of all groups were compared using a one-way analysis of variance test (ANOVA) and a Bonferroni–Holm analysis was performed for pairwise comparison between the groups. The association between modes of failure was examined with Pearson’s chi-square test. Results: Mean shear bond strength values were highest for sound dentin specimens (Group SD 2) bonded with Scotchbond^TM Universal Plus (23.76 ± 7.68 MPa). Sound enamel specimens (Group SE 2) exhibited significantly higher mean bond strength values than MIH-enamel specimens (Group HE 2) when bonded with Scotchbond^TM Universal Plus (19.68 ± 6.25 vs. 11.53 ± 3.29 MPa, p < 0.001). Oxidative pre-treatment followed by resin infiltration significantly improved bond strengths to hypomineralised enamel (Group HE 6) (17.84 ± 2.98 MPa, p < 0.05). Bond strengths to sound and hypomineralised enamel and dentin did not differ significantly for both adhesives. Conclusions: Within the limitations of an in vitro study, oxidative pre-treatment in combination with resin infiltration seems to be beneficial when planning adhesive restorations with composite in hypomineralised enamel. Both Scotchbond^TM Universal Plus and Adper^TM Scotchbond 1XT can be used for bonding of resin composite to MIH-affected enamel and dentin. Full article

This study evaluated the efficacy of various cleaning protocols on two nickel–titanium (NiTi) file systems—RaCe EVO(RE) and EdgeFile X7(EE)—using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Eighty-four NiTi files (42RE, 42EE) were divided into seven groups (n = 12), including a group with unused, sterilized files and a group of used files without cleaning. The remaining files were subjected to simulated clinical use, followed by different cleaning methods, such as soaking in sodium hypochlorite (NaOCl), ethanol wiping (with or without magnification), enzymatic spray, and enzymatic solution. SEM images were imported into ImageJ to quantify surface changes, while EDX assessed elemental composition. The p-value was set to ≤0.05 for significance. Apart from the unused files, calcium and phosphorus—indicators of dentin debris—were present in all groups, especially those cleaned with enzymatic spray (p ≤ 0.0001). Their percentage in RE files soaked in NaOCl or wiped with ethanol was statistically lower than the positive control (p ≤ 0.0001). Post-use, all files showed significantly higher surface asymmetry in Groups 2 and 6 (p = 0.001). Cleaning efficacy depends on the type of NiTi file. RE files responded well to both wiping and soaking, while EE required soaking for effective debris removal. Enzymatic spray was ineffective. Full article

This study aims to evaluate the effect of endodontic irrigation solutions on the bond strength of composites subjected to different aging procedures. Using a shear bond strength test, the effects of sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), and chlorhexidine (CHX) solutions on composite–composite bond strength were examined. The findings revealed that NaOCl alone significantly reduced bond strength, while its adverse effect was completely reversed by the subsequent application of EDTA. CHX, when applied after NaOCl or in combination with EDTA, provided only partial improvement. An aging procedure (5000 thermal cycles) did not have a statistically significant impact on the bond strength. This study provides valuable insights into the roles of endodontic irrigation solutions in composite repair and their implications for restorative dentistry. These findings underline the clinical relevance of selecting appropriate irrigation protocols to preserve or improve bonding during the repair of composite restorations after endodontic treatment. Full article

Background/Objectives: The formation of oral biofilms in periodontal pockets and around dental implants with induction of periodontitis or peri-implantitis is an increasing problem in dental health. The intelligent design of a biofilm makes the bacteria embedded in the biofilm matrix highly tolerant to antiseptic therapy, often resulting in tooth or implant loss. The question therefore arises as to which mouthwashes have eradication potential against oral biofilm. Methods: A human oral biofilm model was developed based on donated blood plasma combined with buffy coats, inoculated with oral pathogenic bacterial species found in periodontal disease (Actinomyces naeslundii, Fusobacterium nucleatum, Streptococcus mitis, and Porphyromonas gingivalis). Over a span of 7 days, we tested different mouth rinsing and antiseptic solutions (Chlorhexidine, Listerine^®, NaOCl, Octenisept^®, and Octenident^®) covering the matured biofilm with 24 h renewal. Phosphate-buffered saline (PBS) was used as a control. Bacterial growth patterns were detected via quantitative polymerase chain reaction (qPCR) after 2, 4, and 7 days of treatment. Results: While all groups showed initial bacterial reduction, the control group demonstrated strong regrowth from day 2 to 4. Listerine showed a near-significant trend toward bacterial suppression. Additionally, strain-specific efficacy was observed, with Octenisept^® being most effective against Streptococcus mitis, Octenident^® and NaOCl showing superior suppression of Actinomyces naeslundii, and Listerine^® outperforming other solutions in reducing Fusobacterium nucleatum. Donor-specific, individual variability further influenced treatment outcomes, with distinct trends in bacterial suppression and regrowth observed across donors. Conclusions: These findings underscore the complexity of biofilm-associated infections and highlight the importance of targeted therapeutic approaches for managing bacterial biofilms. In this experiment, the donor-specific outcomes of the antimicrobial effects of the solutions may indicate that genetic predisposition/tolerance to oral infections appears to play a critical role in the control of oral biofilms. Full article

Optimized in vitro cultivation offers a sustainable solution to enhance blackberry (Rubus spp.) production while reducing pathogen contamination during propagation. This study developed and validated protocols for in vitro cultivation and ex vitro acclimatization of the Tupy, Brazos, and Kiowa cultivars at the Instituto Tecnológico Superior de Los Reyes, Michoacán. A 20 min treatment with 2% sodium hypochlorite (NaOCl) reduced contamination by below 10% and achieved explant survival rates exceeding 95%. Temporary Immersion Systems (TIS) with four to six immersion cycles of 5 min each maximized survival (above 95%) while minimizing necrosis and hyperhydricity and increasing fresh mass. Shoot development was significantly enhanced with 2 mg L⁻¹ 6-benzylaminopurine, and 1 mg L⁻¹ indole-3-butyric acid promoted optimal root formation. Acclimatization success rates exceeded 90% in covered trays compared to significant losses in uncovered trays during early stages. These protocols enabled robust plant development and yields exceeding 10 t ha ⁻¹ during vegetative and reproductive stages, providing a scalable framework for sustainable blackberry production and broader applications in crop propagation. Full article

Unlike other orchids in the Orchidaceae family, Cymbidium goeringii presents significant challenges for in vitro flowering. In this study, through the screening of different basal media, hormone combinations, and other conditions, we developed efficient rhizome regeneration (micropropagation) and in vitro flowering induction systems from protocorm explants of C. goeringii hybrids. To obtain protocorm explants, seeds were pretreated with either NaOH or NaOCl. Our results indicated that NaOH pretreatment enhanced seed germination more effectively than NaOCl, and Knudson C medium proved more suitable for protocorm induction. The resulting protocorms were then used as primary explants for efficient rhizome micropropagation. An orthogonal design identified the optimal combination for rhizome proliferation: 9.0 mg/L 6-BA, 9.0 mg/L NAA, 3.0 mg/L IBA, and 0.1 g/L activated charcoal (Treatment 9), which achieved a proliferation rate of 35.17%. For rhizome differentiation, MS medium supplemented with 10 mg/L 6-BA, 0.1 mg/L NAA, and 0.1 mg/L AgNO₃ (Treatment 6) achieved a 100% differentiation rate and produced 3.93 buds per explant. Building on this optimized micropropagation system, in vitro flowering was induced directly from rhizomes. The most effective medium was MS (1/3N, 3P) supplemented with 9.0 mg/L 6-BA, 0.1 mg/L NAA, and 0.1–0.3 mg/L TDZ (Treatment 6), resulting in a 36% flower bud induction rate and a 16% normal flower bud formation rate. Orthogonal analysis and ANOVA confirmed that 6-BA was the most significant factor influencing floral transition, with the low-nitrogen and high-phosphorus MS (1/3N, 3P) medium also being a key contributor. Consequently, our study has established an efficient rhizome micropropagation system that enables in vitro flowering induction in C. goeringii hybrids within just six months. This represents a substantial 60–80% reduction in the flowering time (from 6–7 years to 1–2 years), compared to the traditional 6–7-year cultivation period. Future work will focus on ex vitro acclimatization, detailed floral-trait validation, and hormone-regime refinement for fast-tracking breeding programs. Full article

Background/Objectives: Root canal infections represent a serious challenge to the success of endodontic treatment. The most commonly used antimicrobial irrigants, such as sodium hypochlorite (NaOCl), have certain limitations, while endodontic biofilms pose a significant microbiological complexity in the endodontic field. Silver nanoparticles (AgNPs) have emerged as a promising irrigant option in root canal treatments; however, few studies are focusing on endodontic biofilms. This work aimed to evaluate the antimicrobial and anti-adherence properties of AgNPs against clinically isolated bacteria taken directly from patients with various pulp and periapical diseases. Methods: AgNPs of two sizes were synthesized and characterized. The bactericidal and anti-adherence activities of AgNPs were evaluated through microbiological assays using experimental in vitro and ex vivo tests on oral biofilms taken from patients with symptomatic apical periodontitis (AAP) and pulp necrosis (PN). NaOCl solution was used as the gold standard. Results: The size of AgNPs was uniformly distributed (13.2 ± 0.4 and 62.6 ± 14.9 nm, respectively) with a spherical shape. Both types of nanoparticles exhibited good antimicrobial and anti-adherence activities in all microbiological assays, with a significant difference from NaOCl for in vitro and ex vivo models (p < 0.05). The inhibitory activity of AgNPs is mainly related to the type of microbiological sample and the exposure time. The antibacterial substantivity of both nanoparticle sizes was time-dependent. Conclusions: AgNPs may represent a promising antimicrobial option as an endodontic irrigant during conventional root canal treatments to prevent and control endodontic infections. Full article

Shell eggs are susceptible to fecal contamination, facilitating the adhesion of microorganisms to the eggshell surface. The consumption of such eggs, especially when unwashed or raw, poses potential health risks to consumers. This study aimed to evaluate the effects of unwashed control, sodium hypochlorite (NaOCl) sanitization (150 ppm), and the combination of NaOCl and ultraviolet (UV) sanitization on the quality of eggs stored at varying temperatures over a four-week period. The findings demonstrated that NaOCl sanitization alone reduced surface bacterial counts by 1.23 log₁₀ CFU/mL, while the combination of NaOCl and UV-C irradiation achieved a greater reduction of 1.48 log₁₀ CFU/mL compared to the unwashed group. After two weeks of storage, unwashed egg groups (UC and UR) exhibited higher eggshell strength compared to NaOCl-sanitized groups (p < 0.05); however, this did not significantly influence internal contamination. Prolonged storage, particularly under refrigeration, led to increased hydroxyl (OH) group peak intensities on the eggshell, indicating dehydration and the formation of fissures in the cuticle. Elevated storage temperatures and extended durations adversely affected egg quality, whereas UV treatment did not have a detrimental impact. In conclusion, to ensure the safety and quality of shell eggs, it is recommended that they undergo NaOCl sanitization, UV irradiation, and be stored under refrigerated conditions. Full article

The effect of root canal irrigants on the mechanical properties of dentin is crucial in endodontic treatment planning. While antiseptics such as sodium hypochlorite and EDTA are widely used, their potential to weaken dentin structure remains a concern. Polyhexanide-based formulations may offer a safer alternative. To assess the impact of a polyhexanide-based antiseptic composition, compared to standard irrigants, on the microhardness, Young’s modulus, and elastic deformation energy of dentin. Sixty extracted human teeth were sectioned and polished to prepare dentin samples. Baseline measurements of Vickers microhardness, Young’s modulus, and elastic deformation work were performed using a Microhardness Tester (CSM Instruments, Switzerland) with a Berkovich indenter. Samples were then divided into six groups (n = 10 per group) and exposed to different irrigants (NaCl 0.9%, NaOCl 3%, chlorhexidine 2%, EDTA 17%, and polyhexanide-based solutions—0.1% and 0.2% Lavasept). Post-treatment measurements were performed. Statistical analysis was conducted using non-parametric tests with Bonferroni correction. Sodium hypochlorite (3%) caused the most pronounced reduction in dentin microhardness and mechanical strength, though not always statistically significant. Polyhexanide-based solutions (0.1% and 0.2% Lavasept) showed a milder effect, with statistically significant changes observed only in elastic deformation energy for 0.2% polyhexanide. EDTA treatment led to severe surface destruction, precluding reliable post-treatment measurements. Polyhexanide-based irrigants demonstrated a more favorable impact on dentin mechanical properties compared to traditional irrigants, supporting their potential use in endodontic protocols aimed at preserving dentin integrity. Full article

Background: With the inclusion of evidence-based dentistry, numerous systematic reviews (SRs) and meta-analyses (MAs) have been conducted in endodontics with the best available scientific evidence to improve diagnosis and treatment. Objective: To synthesize the scientific evidence on the effectiveness of irrigation protocols in endodontic therapy. Methods: Following the umbrella review methodology (UR), a comprehensive literature search was conducted using scientific and grey literature databases. A quality evaluation and a descriptive analysis of the included SRs and MAs were conducted. Quantitative comparability between MAs was carried out. Results: Four descriptive SRs and nine MAs were included. Eight articles evidenced high methodological quality. Studies showed the effectiveness and efficacy depending on the study design, the findings of primary clinical trials, and factors related to the type of irrigant, concentration, volume, and irrigation systems. Variability between irrigants and protocols was observed. Follow-up periods extend from hours to years, and there were different study samples. SRs and MAs evidenced limitations regarding methodological aspects. Low overlap of the primary studies was found. Quantitative analyses indicated greater efficacy in microbial reduction and apical healing in favor of passive ultrasonic irrigation (PUI; RD −0.15; 95% CI −0.28, −0.01; p = 0.03; I2 = 60%; RD −0.09; 95% CI −0.16, −0.02; p = 0.01; I2 = 0%, respectively). Conclusions: This UR highlights the importance of root canal disinfection, emphasizing sodium hypochlorite (NaOCl) as the primary irrigant. Enhanced activation methods, such as PUI and lasers, improve irrigant efficiency, while alternatives like chlorhexidine (CHX) offer better biocompatibility. Standardized protocols and evidence-based clinical guidelines are needed. PROSPERO register: CRD42023409044. Full article

Background/Objectives: The aim of this study was to investigate the effects of periodontal blood flow on the periapical region during various endodontic disinfection procedures. The hypothesis that periodontal blood flow reduces the increase in root surface temperature during disinfection procedures was tested. Methods: One hundred and twenty extracted human teeth were shortened to 11 mm and the root canal was prepared using the F4 ProTaper Gold system. The specimens were covered with wax and then sealed in a thermoforming sheet, leaving a gap of 0.2 mm. Cannulas were attached to simulate stable fluid circulation. Thermographic evaluation was carried out using an infrared camera. The following methods were chosen for disinfection: I, λ445 nm diode laser (0.6 W, cw); II, λ445 nm diode laser, 3 W, pulsed, duty cycle 50%, 10 Hz; III, λ445 nm diode laser, 3 W, pulsed, duty cycle 75%, 10 Hz; IV, λ970 nm diode laser, 2 W, pulsed, duty cycle 50%, 10 Hz; V, λ970 nm diode laser, 2 W, pulsed, duty cycle 75%, 10 Hz; VI, experimental plasma device (2.5 W, 3.7 V); VII, heat plugger (200.0 °C); VIII, NaOCl 3% (60 °C). The results were analyzed statistically using the Kruskal–Wallis test. When there were significant differences between the groups (p < 0.05), the pairwise Mann–Whitney test with sequential Bonferroni correction was applied. Results: The smallest temperature changes, with a median value of 0.82 °C (max. 2.02 °C, min. 0.15 °C, IQR 0.87 °C), were observed using the laser at a setting of λ445 nm, 0.6 W cw, and a circulation rate of 6 mL/min. The highest temperature changes were measured at a fluid circulation rate of 0 mL/min with a laser setting of λ445 nm, 3 W, pulsed, duty cycle 75% with a median value of 21.7 °C (max. 25.02 °C, min. 20.29 °C, IQR 2.04 °C). Conclusions: Disinfection procedures with laser, NaOCl, and an experimental plasma device can lead to an increase in root surface temperature. With the exception of the heat plugger, no significant temperature changes were observed. This study was conducted in vitro, which may limit the direct applicability of the results to clinical scenarios. Nevertheless, the simulation of blood flow showed a thermally protective effect, suggesting that clinical protocols should consider this variable when selecting thermal disinfection methods. These results support the hypothesis that periodontal blood flow may have a potentially positive influence on temperature changes during disinfection procedures. 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