Influence Of Sodium Hypochlorite Research Articles

Influence of sodium hypochlorite on cyclic fatigue resistance of nickel-titanium instruments: A systematic review and meta-analysis of in vitro studies.

This systematic review/meta-analysis investigated the influence of NaOCl on cyclic fatigue resistance of endodontic NiTi instruments. A systematic search until July 2022 in PubMed/MEDLINE, Embase, Scopus, Web of Science, SciELO, Cochrane Library, and grey literature was conducted. According to the PECOS strategy, only in vitro studies evaluating the effects of NaOCl on the cyclic fatigue resistance of NiTi instruments were eligible. Cyclic fatigue resistance was the primary outcome. A modified Joanna Briggs Institute's Checklist was used for risk of bias assessment. Of the 2,445 records screened, 37 studies were included. Most studies used simulated canals made of stainless-steel block with severe to moderate curvatures. NaOCl concentration varied from 1-6%, mainly at 37°C. Regarding fatigue resistance, 23 studies using 1.2% to 6% NaOCl showed a reduction in the resistance compared to the control groups, especially when pre-heated. Four meta-analyses were performed according to the tested NiTi systems. The meta-analyses indicated that the PTU F2 files had higher reduction of fatigue resistance after exposure to 5.25% NaOCl; no differences between NaOCl and no immersion were observed for Reciproc R25, WaveOne 25.08, and WaveOne Gold Primary files. Included studies had low risk of bias. NaOCl appears to reduce cyclic fatigue resistance of certain NiTi files, especially when they are pre-heated, particularly in conventional NiTi files compared to some heat-treated instruments. It is possible that the temperature of the solution may have a greater influence on resistance than NaOCl itself. Important to note that an overall tendency toward no significant influence was observed among various systems. Precautions are necessary when a pre-heated high-concentration NaOCl is used to enhance its properties during root canal preparation, mainly using conventional wire.

Influence of sodium hypochlorite used in combination with EDTA versus sodium hypochlorite mixed with etidronate irrigants on coronal fracture resistance of endodontically treated bleached teeth (A comparative in-vitro study)

Influence of sodium hypochlorite used in combination with EDTA versus sodium hypochlorite mixed with etidronate irrigants on coronal fracture resistance of endodontically treated bleached teeth (A comparative in-vitro study)

A Novel and Practical Synthesis of Tryptanthrin

AbstractTryptanthrin was synthesized through a two-step reaction of oxidation and condensation in a one-pot method, with isatin and sodium hypochlorite as starting materials. The influence of sodium hypochlorite, acetonitrile dosage, oxidation reaction temperature, and reaction time on the yield of the target product during the reaction was investigated. The following optimal reaction conditions were obtained: the ratio of n (isatin) to n (sodium hypochlorite) was 2:1, and the reaction time was 6–8 hours at room temperature. The structure of tryptanthrin was confirmed by matching the IR, NMR, and mass data with the literature report. The study shows that the chemical reaction route designed in this report is short, with high yield and purity of the target product. Its low production cost and simple operation method are expected to be applicable to industrial production.

Overhauling the Effect of Surface Sterilization on Analysis of Endophytes in Tea Plants

Increasing evidence shows that plant Endophytes play a crucial role in the fitness and productivity of hosts. Surface sterilization is an indispensable process before high-throughput sequencing (HTS) and tissue separation of plant endophytes, but its potential impact on the composition and diversity of endophytes has rarely been investigated. In the present work, the influence of sodium hypochlorite (NaClO) on the diversity of endophytic bacteria and fungi in leaves and stems of tea plants was investigated. We found that the diversity of bacterial endophytes was significantly affected by the concentration of NaClO as well as the pretreatment time. Pretreatment with 0.5% NaClO for 8 min and 2.0% NaClO for 3 min were suitable for the tea plant leaves and stems, respectively, but the effects of NaClO on the diversity of fungal endophytes were limited according to the results from HTS. Regardless of NaClO sterilization, most of the endophytes in tissues, such as the dominant taxa, could not be Isolated by using the regular culture-dependent approaches. Collectively, our results demonstrated that the pretreatment with NaClO should be modified to precisely understand the diversity of endophytes from different tissues of tea plants and also indicate that more attention should be paid to establish specific culture-dependent protocols for the isolation of plant endophytes.

Influence of sodium hypochlorite on cyclic fatigue resistance in niti controlled memory endodontics rotary instruments: an experimental evaluation

Resumo Introdução É importante saber se o hipoclorito de sódio (NaOCl) influencia a resistência à fadiga cíclica das limas de níquel-titânio (NiTi). Objetivo Avaliar a influência de NaOCl 2,5% na resistência à fadiga cíclica de dois sistemas de NiTi. Material e método: 40 instrumentos rotatórios – 20 TruNatomy® (TRU, Dentsply Sirona, Maillefer, Ballaigues, Suíça) e 20 Prodesing Logic2® (PDL2, Bassi, Belo Horizonte, Minas Gerais, Brasil) – foram aleatoriamente distribuídos em 4 grupos experimentais (n = 10) imersos em água destilada (H2O) e NaOCl 2,5% em temperatura a 37°C. Foram submetidos a testes de fadiga cíclica mensurando o número de ciclos para fratura (NCF) e análise dessas superfícies pós-teste em microscópio eletrônico por varredura. Para a análise estatística entre os grupos, foi aplicada a análise de variância (ANOVA), complementada com o pós-teste de Tukey. Resultado Houve diferença estatística em todos os grupos (P < 0,05). Os instrumentos PDL2 obtiveram maior resistência à fratura nas condições em H2O e em NaOCl 2,5% comparados aos instrumentos TRU. Na análise de grupos de instrumentos nas soluções de NaOCl e H2O, foi observado que o NaOCl 2,5% diminuiu o NCF. Conclusão A resistência à fadiga cíclica dos instrumentos TRU e PDL2 diminuiu com NaOCl 2,5%. Os instrumentos PDL2 foram mais resistentes à fratura em relação aos instrumentos TRU.

Influence of sodium hypochlorite and ultrasounds on surface features and chemical composition of Biodentine tricalcium silicate-based material.

Biomaterials are subjected to various factors during endodontic workflow. The aim was to evaluate the influence of different concentrations of sodium hypochlorite and ultrasound activation on the features and chemical composition of Biodentine. Fifty-four Biodentine samples were divided into 3 groups based on the material setting time. They were subjected to different modes and times of 2% and 5.25% NaOCl irrigation with or without ultrasounds, 12 min (group I), 45 min (group II) and 24 h (group III) after the material mixing. Visual assessment of the sample's surface was performed using the scanning electron microscope and chemical analysis was made with energy dispersive spectroscopy. Both NaOCl irrigation and ultrasounds affected the surface of the material; however, they did not change its chemical composition. The irrigation enhanced by ultrasounds following the placement of Biodentine should be performed after a longer material setting time. The immediate use of ultrasounds is not recommended.

Pharmacological Correction of Experimental Acute Toxic Hepatitis

The aim of study was to develop new methods of treatment of acute toxic hepatitis. To achieve this objective, the authors investigated dynamics of pathological changes in the hepatic tissue under acute intoxication followed by the pharmacological correction with sodium hypochlorite.Material and methods. The study included 45 male rats that were subjected to the experimental simulation of acute toxic hepatosis. Group 1 included intact animals; group 2 included animals that were intragastrically administered allyl alcohol resulting in acute toxic hepatosis; group 3 included rats with acute toxic hepatosis caused by allyl alcohol introduction that was corrected by sodium hypochlorite; group 4 included animals with acute toxic hepatosis corrected by essentiale N; group 5 included animals with acute toxic hepatosis corrected by the combined application of sodium hypochlorite and essentiale N. On the 6th day the animals were removed from the experiment with the followed histological examination of the hepatic tissue.Results. The introduction of allyl alcohol was accompanied by significant changes in hepatocytes expressed by dystrophic, necrotic processes and circulatory disorders of the hepatic lobules. Pharmacological correction by sodium hypochlorite, essential H, or their combination did not result in the complete histological recovery of hepatocytes; however, the degree of fatty degeneration decreased significantly under the influence of sodium hypochlorite or its combination with essentiale N.Conclusions. The application of sodium hypochlorite as a monotherapy or in combination with essential N in acute toxic hepatitis has allowed to relieve the severity of fatty liver disease. 0.03% solution of sodium hypochlorite can be effective as both - an independent method for treating acute toxic hepatitis, and in combination with other hepatoprotectors.

New insights into enhancement of sodium hypochlorite on formation and properties of anodic films on Ti6Al4V alloy

Anodic films were successfully fabricated on Ti6Al4V alloy by anodic oxidation method in an environmental friendly electrolyte with and without sodium hypochlorite. The anodic films were characterized by means of the scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Results revealed that the addition of sodium hypochlorite leads to the ultrafast growth of oxide films, and results in the significant changes of morphology and thickness. The influence of sodium hypochlorite on formation and crystallization of oxide films as a function of anodizing time was discussed. Meanwhile, potentiodynamic electrochemical tests and dry sliding wear tests were performed to evaluate the corrosion resistance and tribological properties of oxide films. It was found that the oxide film fabricated with the existence of sodium hypochlorite had improved corrosion resistance and tribological properties than the one formed without sodium hypochlorite. Moreover, the effect mechanism of sodium hypochlorite on the growth rate and surface morphologies of oxide films during the anodizing process was discussed. It was found that hypochlorite ions participated in the reaction on anode which causes the rapid growth of oxide films and then affect the whole anodizing process.

Antioxidant defense system state in blood plasma and heart muscle of rats under the influence of histamine and sodium hypochlorite

There is a wide spectrum of antihistamine drugs in the pharmaceutical market, however all these chemical preparations cause side effects. Therefore, new alternative ways for histamine detoxication are to be found. For this aim in our experiment sodium hypochlorite was used because its solution possesses strong oxidizing properties. The influence of histamine and sodium hypochlorite on the antioxidant defence system state of blood plasma and cardiac muscle in rats has been researched. It was shown, that the investigated factors result in the disruption of the antioxidant system. It was found that histamine injection in concentration of 1 and 8 μg/kg in plasma leads to the increase of superoxide dismutase activity during all the experiment. When studying enzymes, that catalyze hydroperoxides and H2O2 decomposition it was shown that under the influence of histamine in a dose 1 μg/kg, the glutathione peroxidase activity increased on the 1st day of the experiment. However, on the 7th day of the experiment the increase of both glutathione peroxidase and catalase activity was fixed. The deviation in superoxide dismutase function in rats plasma under the action of sodium hypochlorite has been established. The activity of enzymes that decompose H2O2 and hydroperoxides were inhibited. Under the influence of histamine in the heart tissues we have stated the disturbance of superoxide dismutase work and increase ofcatalase activity and decrease of glutathione peroxidase activity. The influence of sodium hypochlorite on the myocardium of intact animals as well as joint influence of sodium hypochlorite and histamine result in the increase of superoxide dismutase and catalase activity and lead to the considerable decline of activity of glutathione peroxidase.

Influence of sodium hypochlorite used for chemical enhanced backwashing on biophysical treatment in MBR

Many attempts have been made to control fouling in membrane bioreactors (MBRs) to sustain permeability through relaxation, backwashing and chemical cleaning. Sodium hypochlorite is one of the most useful chemical agents used to control fouling in chemically enhanced backwashing (CEB) of MBRs. However, sodium hypochlorite has the potential to adversely affect microorganisms because CEB is usually carried out within the bioreactor. Hence, this study investigated how sodium hypochlorite influences activated sludge from the viewpoint of microorganism properties and suggests the limit of sodium hypochlorite dosage. Activated sludge was evaluated using the substance removal rate, extracellular polymeric substances (EPSs), particle size distribution (PSD) and permeability. It was shown that 1mg-NaOCl/g-MLVSS had a slight superiority in nutrient removal compared to 5mg-NaOCl/g-MLVSS. On the other hand, the NH4-N removal ratio of 1mg-NaOCl/g-MLVSS was bigger than that of 5mg-NaOCl/g-MLVSS in nitrification for 3h from the time of sodium hypochlorite addition. While 1mg-NaOCl/g-MLVSS showed a similar tendency with the reference sludge in the case of EPSpolysaccharide, 5mg-NaOCl/g-MLVSS generated EPSpolysaccharide 1.5 times as much as that of 1mg-NaOCl/g-MLVSS. Also, according to particle size distribution, the average floc size of 5mg-NaOCl/g-MLVSS was changed from 43.63 to 36.98μm. As a result, the sludge of 5mg-NaOCl/g-MLVSS had a much higher potential for increase than the reference sludge in membrane fouling. Moreover, a microfiltration experiment confirmed that 5mg-NaOCl/g-MLVSS had a double rate increase of resistance compared with 1mg-NaOCl/g-MLVSS.

Influence of Sodium Hypochlorite on Er:YAG Laser-Irradiated Dentin and its Effect on the Quality of Adaptation of the Composite Restoration Margins

The aims of this in vitro study were to evaluate: (1) the influence of 5% NaOCl application on Er:YAG-irradiated dentin; and (2) its effect on the quality of adaptation of the composite restoration margins. Previous research has shown that Er:YAG dentin irradiation produces a thermally affected tissue layer that results in lower bond strength than that of nonirradiated dentin. The removal of this thermally-affected layer may enhance the quality of dentin bonding. Forty-nine caries-free extracted human molars were transversely sectioned in order to totally expose the dentin. Four standardized cavities were created on the dentinal surface of each molar. First, two cavities were irradiated with Er:YAG laser (2.94 nm): 150 mJ, 10 Hz, variable square pulse (VSP) mode (100 μsec), beam diameter=0.9 mm, speed of irradiation=1 mm/sec, 20% air and 20% water. Then, one of irradiated cavities and one of nonirradiated cavities were treated for 30 sec with 5% NaOCl solution. Finally, they went through a standard bonding treatment for composite restoration, etching, bonding, and composite filling. We obtained four groups of cavities: (1) one control group of nonirradiated cavities not pretreated with NaOCl; (2) one group of nonirradiated cavities, pretreated with NaOCl; (3) one group of irradiated cavities, not pretreated with NaOCl; and (4) one group of irradiated cavities, pretreated with NaOCl. All samples were subjected to thermocycling. Every cavity was immersed into a 0.5% solution of methylene blue. The percentage of dye penetration (microleakage) in the composite-dentin interface was evaluated. Six molars were analyzed by scanning electron microscope. Dye infiltration depth was significantly reduced in irradiated cavities treated with 5% NaOCl solution. The application of a 5% NaOCl solution on Er:YAG irradiated cavities can significantly improve the marginal quality of composite bonding.

Вплив гіпохлориту натрію на прооксидантно-антиоксидантний гомеостаз зародків в’юна протягом раннього ембріогенезу

The article contains data regarding the influence of sodium hypochlorite on the processes of free radical oxidation and antioxidant system of loach Misgurnus fossilis L. embryos in early stages of the development. It was showed that the effect of sodium hypochlorite added to the medium where the embryos develop, leads to disruption of prooxidation-antioxidant loach Misgurnus fossilis L. embryos homeostasis during early embryogenesis. It is proved that the sodium hypochlorite solution is empowered prooxydant manifestations in the early stages of embryogenesis wich are investigated and is inhibiting certain enzymes of antioxidant protection. It was found that the embryos at the 16 blastomeres stage of early embryogenesis are most sensitive to the action of sodium hypochlorite. Embryos at the 1024 blastomeres stage (10 division) are the most resistant to sodium hypochlorite as the content of lipid peroxidation products is reduced compared with control, whereas the activity of superoxidedismutase and glutathione peroxidase is within control value. Keywords : loach embryo, lipid peroxidation, superoxide dismutase, catalase, glutationperoxydasе, glutathione reduced, sodium hypochlorite.

Активність Nа+, K+-АТФ-ази мембран зародків в’юна впродовж раннього ембріогенезу за дії гіпохлориту натрію

The paper contains data regarding the influence of sodium hypochlorite on the activity of embryos membrane Na + , K + -ATP-ase of loach Misgurnus fossilis L. in early stages of the development. We showed that sodium hypochlorite added to the medium where the embryos develop, caused dose-dependent inhibition of the membranes Na + , K + -ATP-ase activity. We suggested that effects of sodium hypochlorite were due to oxidizing properties and its ability to disrupt membrane integrity, in particular, damaging proteins and lipids. Keywords : membrane transport, plasma membrane, loach embryos, Na + , K + -activated Mg 2+ -dependent ATP-ase, sodium hypochlorite.

Influence of sodium hypochlorite and edta on the microtensile bond strength of a self-etching adhesive system

Chemical substances used during biomechanical preparation of root canals can alter the composition of dentin surface and affect the interaction with restorative materials.ObjectiveThe purpose of this study was to evaluate the microtensile bond strength (µTBS) of a self-etching adhesive system to dentin irrigated with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (eDTA).Material and MethodsThirty human third molars were sectioned 3 mm below the occlusal surface, polished with 600- to 1200-grit silicon carbide papers, and randomly divided into 3 groups: G1 (control): no irrigating solution; G2: 1% NaOCl; and G3: 1% NaOCl followed by the application of 17% eDTA. The specimens received the self-etching adhesive system (XeNO III - Dentsply), restored with microhybrid composite resin (Z250 - 3M ESPE), sectioned and trimmed to create 4 hourglass-shaped slabs of each tooth. The slabs were tested in microtensile strength in a universal testing machine (emic DL 2000) at a crosshead speed of 0.5 mm/min until fracture. The results were analyzed statistically by ANOVA and Newman-Keuls test.ResultsMean µTBS values and standard deviations in MPa were: G1 = 11.89 ± 4.22; G2 = 19.41 ± 5.32; G3 = 11.34 ± 4.73. 1% NaOCl increased the adhesive resistance significantly (p<0.001/ F=22.5763). The application of 1% NaOCl/17% eDTA resulted in statistically similar µTBS to the control group.ConclusionsNone of the irrigants affected negatively the µTBS of XeNO III to dentin. The use of 1% NaOCl alone resulted in higher bond strength than the other treatments. The combination of 1% NaOCl and 17% eDTA produced similar bond strength to that of untreated dentin.

Influence of Sodium Hypochlorite on Mechanical Properties of K3 Nickel-Titanium Rotary Instruments

Several studies have evaluated the influence of various factors on the fracture of nickel-titanium endodontic rotary instruments. The present study analyzed the influence of sodium hypochlorite on flexural fatigue and torsional properties of nickel-titanium endodontic rotary instruments. New files and files previously exposed to sodium hypochlorite were tested for flexural fatigue and for resistance to fracture by twisting. The t test was used to compare the groups for number of cycles, angle of rotation, and maximum torque required to fracture. No statistical difference existed between these groups. Scanning electron microscopy analysis showed no evidence of localized corrosion in files exposed to sodium hypochlorite solution. These results suggest that the exposure to sodium hypochlorite has no influence on resistance to fracture of K3 rotary instruments.

The influence of sodium hypochlorite and EDTA on the chemical composition of dentine

Aim To characterise changes in the chemical composition of dentine after exposure to sodium hypochlorite and ethylenediaminetetracetic acid (EDTA) using ATR‐FTIR and Raman spectroscopy.Methodology Crown dentine was acquired from recently extracted molars stored in formal‐saline (group A) or saline and frozen at −2oC (group B); it was then ground and sieved into a range of particle sizes. Samples from both groups (n = 5 each) were analysed with FTIR to investigate the influence of storage medium and to assign FTIR spectral peaks for collagen, carbonate, phosphate. As no differences were found, the samples were pooled for subsequent experiments. Ten samples of particle size range 38–75 μm were used to study the effect of mass ratio of NaOCl (2.5%): dentine over 5–10 min. Thirty samples of all sizes were reacted with 2.5% sodium hypochlorite at 1:0.5 (dentine:NaOCl) mass ratio for 2–10 min; EDTA (n = 90) for 5–1440 min; NaOCl for 10 min followed by EDTA for 10 mins (n = 30); the latter samples were further exposed to NaOCl for 10 min after obtaining FTIR spectra.Results FTIR spectra from the surface of the particles (~1.5 μm depth) were obtained for all the samples and Raman spectra (40 μm depth) were obtained for one sample each reacted either with NaOCl or EDTA. Spectral peak assignment was confirmed by previous data. Storage media had no effect on outcome measures used. The dentine:NaOCl ratio influenced collagen depletion. NaOCl affected the collagen FTIR peaks, mostly in the first 2–4 min, but only influenced the phosphate and carbonate peaks slightly. EDTA affected the phosphate:collagen peaks, which reduced over time, whilst the collagen peak values showed an increase. The two solutions (NaOCl and EDTA) used alternately, respectively increased collagen or phosphate peaks depending on the final solution used.Conclusions These series of investigations confirmed that sodium hypochlorite depletes the organic content of dentine and EDTA depletes the inorganic content. Used alternately, they have the ability to progressively degrade dentine structure.

Photolysis and photocatalysis of bisphenol A: identification of degradation products by liquid chromatography with electrospray ionization/time-of-flight/mass spectrometry (LC/ESI/ToF/MS)

Bisphenol A is a commonly known endocrine-disrupting compound detected in environmental water samples. The persistence of this compound has been studied by photolysis and photocatalysis studies. In this work, several experiments were performed in order to identify the degradation products under various conditions and in different types of matrices (deionized and waste water). These studies included the influence of sodium hypochlorite (NaClO), commonly present in drinking water, on the generation of chlorine by-products of bisphenol A. The effect of catalyses in solar degradation studies was evaluated as well. The identification of the degradation products was accomplished by liquid chromatography/time-of-flight/mass spectrometry (LC-ToF-MS), which provided highly selective information about elemental compositions. Accurate mass measurements for three main degradation products permitted the postulation of proposed empirical formula in this study. Some of the degradation products were formed in waste water matrices, thus suggesting their potential presence in environmental conditions and in drinking water.

Influence of sodium hypochlorite on fracture properties and corrosion of ProTaper Rotary instruments

To evaluate the influence of immersion in NaOCl on resistance to cyclic fatigue fracture and corrosion of ProTaper NiTi Rotary instruments. A total of 120 new ProTaper NiTi Rotary files (F2) were randomized and assigned to three different groups of 40 each. Group 1 was the control group; 20 mm (excluding the shaft) of group 2 instruments were immersed in 5% NaOCl at 50 degrees C for 5 min; instruments in group 3 were completely immersed in 5% NaOCl at 50 degrees C for 5 min. All instruments were then tested for cyclic fatigue, recording the time in seconds to fracture. Data were analysed by the Kruskall-Wallis test and post-hoc multiple comparisons (P < 0.05). Micromorphological and microchemical analyses were also completed by means of a field emission scanning electron microscopy (SEM) on those instruments in group 3 that had undergone early fracture. Instruments in group 3 had a significantly lower resistance to fracture because of cyclic fatigue than those in groups 1 and 2 (P < 0.001). In some instruments in group 3, early fracture occurred after only a few seconds of fatigue testing. SEM observations revealed evident signs of corrosion of the fractured instruments. Group 3 had significantly reduced resistance to cyclic fatigue compared with instruments in groups 1 and 2. The phenomenon of early fracture may be attributed to galvanic corrosion induced by the presence of dissimilar metals, where one acts as the cathode of a galvanic couple, established when the instrument is immersed in NaOCl solution. The NiTi alloy may acts as the anode and thus undergoes corrosion.

Influence of sodium hypochlorite on the permeability and structure of cervical human dentine

The effect of 5% sodium hypochlorite and 35% hydrogen peroxide on dentine samples in vitro was investigated. It was demonstrated that both 5% NaOCl and 35% H2O2 depletes the dentine, which can be recorded as weight loss. Sodium hypochlorite removes approximately 14% of dry weight from dentine samples in 24 h; hydrogen peroxide is half as destructive. The hydraulic conductance (Lp) of dentine after treatment with NaOCl is increased over 100%. It is suggested that the use of high concentrations of sodium hypochlorite during root canal treatment may negatively affect the integrity of the root canal wall thereby allowing increased access of caustic bleaching fluids to cervical vital tissues.