Root canal irrigants effect on the compressive strength and calcium ion release of Biodentine.

Compressive strength and calcium ion release are integral properties of Biodentine for its enhanced efficiency. The present study evaluated the effects of Dual Rinse HEDP (DR HEDP), ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite (NaOCl) on the calcium ion release and compressive strength of Biodentine. Eighty Biodentine specimens were moulded and randomly divided into four groups (n = 20). Samples in group 1 were treated with 17 % EDTA; group 2 with DR HEDP; group 3 with 2.5 % NaOCl; and group 4 with distilled water. Samples were immersed in 10 mL of the test solutions for 1 min. The mean concentration of the calcium ion released was measured using atomic absorption spectrophotometry. The remaining 40 samples were tested for their compressive strength. Significant differences were determined among all the irrigants tested for calcium ion release and compressive strength. Samples treated with NaOCl had the lowest calcium ion release, while samples treated with 17 % EDTA had the largest calcium ions. No significant differences were measured between DR HEDP or distilled water. For compressive strength, samples treated with 2.5 % NaOCl had the lowest strength, while the highest values were obtained with distilled water. There was a significant difference between DR HEDP and EDTA, in which EDTA reduced the compressive strength significantly more than DR HEDP. DR HEDP had less detrimental effect on the calcium ion release and compressive strength of Biodentine.

A Comparative Evaluation of the Effect of Different Endodontic Irrigating Solutions on Microhardness of Root Canal Dentin: An in vitro Study.

Statement of the Problem: During endodontic therapy, irrigation solutions applied in the root canal may affect the physicochemical properties of the dentinal wall, thereby changing its microhardness. This may adversely affect the sealing ability and adhesion of dental materials. Therefore, many studies have focused on the search for an ideal root canal irrigant that has a minimal effect on dentinal microhardness. Purpose: This in vitro study was conducted to determine the changes in dentin microhardness after root canal irrigation with different endodontic irrigants. Materials and Method: Ninety-five freshly extracted maxillary central incisor teeth with straight single canals were selected. These teeth were sectioned transversely at the level of the cementoenamel junction. The working length of each tooth was determined, and canal space was prepared by the HyFlex CM rotary file system. During instrumentation, normal saline was used for irrigation. Then, teeth were split longitudinally into two segments. According to the irrigating solution employed, samples were divided into five groups (n=19): normal saline (Group A), 3% sodium hypochlorite (Group B), 2% chlorhexidine (Group C), 5% calcium hypochlorite (Group D), and 0.2% nanochitosan (Group E).3 mL of the corresponding irrigating solution was administered for total15 minutes in each prepared sample. The Vickers micro-hardness tester was then used to assess micro-hardness. The data was analyzed using one-way analysis of variance (ANOVA). Results: All tested irrigating solutions decreased the dentinal microhardness. Samples irrigated with 5% calcium hypochlorite demonstrated dentinal microhardness of 42.43±1.62, which is the lowest among all the tested groups, followed by nano chitosan, sodium hypochlorite, and chlorhexidine. Samples treated with control group (saline) demonstrated the maximum microhardness of dentin in the present study. Conclusion: Within the limitations of this research, it can be concluded that the tested novel irrigating solutions, 5% calcium hypochlorite and 0.2% nanochitosan, were more detrimental to radicular dentin microhardness when compared with conventional endodontic irrigants.

Comparative Evaluation of Microbial Reduction Using Silver Diamine Fluoride, Azadirachta indica (Neem) and Sodium Hypochlorite as Root Canal Irrigants after Biomechanical Preparation in Uniradicular Canals: An In Vivo Study.

Background: It is difficult to completely eradicate microorganisms from the infected root canal system. Intracanal irrigants seem necessary for eradication of infected tissues and microorganisms in addition to mechanical debridement. Continuous use of chemical antimicrobial agents leads to serious side effects. Therefore, the need arises for alternative agents to overcome the disadvantages of their chemical counterparts. Aim: To evaluate and compare the antimicrobial efficacy of three endodontic irrigants against clinically isolated bacteria found in root canals containing necrotic pulp. Materials and methods: Preirrigation sample were collected using sterile paper points and sent for microbial count. Chemomechanical preparation was performed, and the root canals were irrigated with 5 mL of test samples. After 3 days, the patient was recalled, and a postirrigation sample was collected and sent for microbial count. Result synthesis: Both 3.8% silver diamine fluoride (SDF) and 3% sodium hypochlorite (NaOCl) showed a superior capacity to sterilize the root canals compared to the neem group. Conclusion: The use of SDF as an endodontic irrigant is feasible as it effectively removes the microbes present in the canal. Clinical significance: Silver diamine fluoride has not been shown to be cytotoxic or carcinogenic, unlike NaOCl, suggesting it could be used as a potential endodontic irrigant. However, few studies have evaluated the antimicrobial efficacy of SDF as an endodontic irrigant. How to cite this article: Raj S, Sharma A, Dhinsa K, et al. Comparative Evaluation of Microbial Reduction Using Silver Diamine Fluoride, Azadirachta indica (Neem) and Sodium Hypochlorite as Root Canal Irrigants after Biomechanical Preparation in Uniradicular Canals: An In Vivo Study. Int J Clin Pediatr Dent 2024;17(6):625-629.

Clinical and Radiographic Evaluation of Diode and Er,Cr:YSGG Lasers as an Alternative to Formocresol and Sodium Hypochlorite for Pulpotomy Techniques in Primary Molars: A Randomized Controlled Clinical Trial.

Background Pulpotomy treatment is one of the vital pulp therapies that can play a major role in the preservation of primary teeth until their natural exfoliation. The objective of this current clinical trial was to assess the clinical and radiographical success of diode and Er,Cr:YSGG lasers as a viable alternative to formocresol (FC) and sodium hypochlorite in the primary molar pulpotomies. Materials and methods Sixty primary molars were selected and randomly allocated to four groups. All treatment groups followed the same clinical protocol, except for the techniques used for hemostasis of the pulpotomy sites. In group A, hemostasis was achieved by applying a 1:5 dilution of FC solution, whereas in group B, 3% sodium hypochlorite was applied to achieve hemostasis. In group C, exposure to a diode laser of 940 nm was performed, whereas for group D, erbium laser irradiation with Er,Cr:YSGG laser of 2,780 nm was employed to achieve hemostasis. Radicular pulp stamps were covered with a 2 mm layer of mineral trioxide aggregate (MTA) paste. Stainless steel crowns were utilized for the final restorations of the primary teeth. The clinical and radiographic outcomes were evaluated at the six- and 12-month follow-up intervals. The investigation was registered with the ClinicalTrials.gov Protocol and Registration System (ID: NCT06002646). Results The overall clinical and radiographic success rates of pulpotomy were 92.3% for FC, 89% for sodium hypochlorite, 98.3% for a diode laser, and 98.7% for Er,Cr:YSGG lasers. There were no statistically significant differences among the four groups (p > 0.05). Conclusions Both the diode and Er,Cr:YSGG lasers showed outcomes comparable to those of FC and sodium hypochlorite. Therefore, they could be promising alternatives to primary tooth pulpotomies.

Reliable assessment and prediction of moderate preoxidation of sodium hypochlorite for algae-laden water treatment.

Chemical moderate preoxidation for algae-laden water is an economical and prospective strategy for controlling algae and exogenous pollutants, whereas it is constrained by a lack of effective on-line evaluation and quick-response feedback method. Herein, excitation-emission matrix parallel factor analysis (EEM-PARAFAC) was used to identify cyanobacteria fluorophores after preoxidation of sodium hypochlorite (NaClO) at Excitation/Emission wavelength of 260(360)/450 nm, based on which the algal cell integrity and intracellular organic matter (IOM) release were quantitatively assessed. Machine learning modeling of fluorescence spectral data for prediction of moderate preoxidation using NaClO was established. The optimal NaClO dosage for moderate preoxidation depended on algal density, growth phases, and organic matter concentrations in source water matrices. Low doses of NaClO (<0.5 mg/L) led to short-term desorption of surface-adsorbed organic matter (S-AOM) without compromising algal cell integrity, whereas high doses of NaClO (≥0.5 mg/L) quickly caused cell damage. The optimal NaClO dosage increased from 0.2-0.3 mg/L to 0.9-1.2 mg/L, corresponding to the source water with algal densities from 0.1 × 106 to 2.0 × 106 cells/mL. Different growth stages required varying NaClO doses: stationary phase cells needed 0.3-0.5 mg/L, log phase cells 0.6-0.8 mg/L, and decaying cells 2.0-2.5 mg/L. The presence of natural organic matter and S-AOM increased the NaClO dosage limit with higher dissolved organic carbon (DOC) concentrations (1.00 mg/L DOC required 0.8-1.0 mg/L NaClO, while 2.20 mg/L DOC required 1.5-2.0 mg/L). Compared to other predictive models, the machine learning model (Gaussian process regression-Matern (0.5)) performed best, achieving R2 values of 1.000 and 0.976 in training and testing sets. Optimal preoxidation followed by coagulation effectively removed algal contaminants, achieving 91%, 92%, and 92% removal for algal cells, turbidity, and chlorophyll-a, respectively, thereby demonstrating the effectiveness of moderate preoxidation. This study introduces a novel approach to dynamically adjust NaClO dosage by monitoring source water qualities and tracking post-preoxidation fluorophores, enhancing moderate preoxidation technology application in algae-laden water treatment.

Antibiofilm activity of sodium hypochlorite against enterococcus faecalis using four irrigant activation protocols.

Aims: The aim of the study was to compare the activity of sodium hypochlorite (NaOCl) against Enterococcus faecalis when used with four different irrigation protocols. Methodology: Sixty-five single-rooted mandibular premolars with closed apex were prepared till size 35/0.04. The specimens were sterilized and infected with E. faecalis colonies that were cultured separately. The canals were randomly divided into four experimental groups based on irrigation activation protocol, with each group having 15 specimens each - Group 1: control, Group 2: manual dynamic agitation (MDA), Group 3: passive ultrasonic irrigation (PUI), Group 4: intracanal heating (ICH), and Group 5: passive ultrasonic irrigation followed by ICH (PUI ICH). The dentinal shavings were collected and sampled before (S1) and after (S2) the different irrigation techniques were performed. The colony-forming units were counted, and the bacterial reduction was calculated for each group. Results: A significant reduction in the number of E. faecalis colonies was observed for all the experimental groups (P < 0.001). The groups with ICH of NaOCl showed a considerable reduction in bacterial colonies than other groups (P < 0.001), with Group 5 that combined ultrasonics with ICH showed the highest reduction. Conclusion: ICH of NaOCl may be used as an adjunct to root canal irrigation to reduce the bacterial concentration from root canal spaces.

Does increase in temperature of sodium hypochlorite have enhanced antimicrobial efficacy and tissue dissolution property? - A systematic review and meta-regression.

Objectives: The objective of this study was to analyze the available evidence on the performance of increase in temperature of sodium hypochlorite on its antimicrobial efficacy and tissue dissolution property. Materials and Methods: The study was conducted according to PRISMA guidelines, and a modified Joanna Briggs Institute (JBI) tool was used for quality assessment of the included studies. Two reviewers independently performed an electronic search in four databases along with the reference lists of the included articles. Results: This systematic review included a total of 12 studies: antimicrobial efficacy (n = 6) and tissue dissolution property (n = 6). For the studies that were chosen, the overall risk of bias was moderate. Quantitative assessment through meta-regression was performed for tissue dissolution property. Low-concentration sodium hypochlorite irrigant (≤3%) shows a 0.13-unit times increase in tissue dissolution ability with a degree rise in temperature although not statistically significant. Conclusion: Due to inconsistency in the study parameters, results pertaining to the exclusive effect of increase in the temperature of sodium hypochlorite remain inconclusive.

Evaluation of pulp tissue dissolving efficiency of sodium and calcium hypochlorite solutions activated by ultrasonics and laser: an in vitro study.

OBJECTIVES: This study aimed to compare the tissue dissolving capacities of sodium and calcium hypochlorite [NaOCl and Ca(OCl)2] solutions applied without activation or with two irrigant activation methods. MATERIALS AND METHODS: One hundred and eight dentin cavities were prepared. Preweighed tissue pieces were placed in these dentin cavities, and samples were divided into nine groups of twelve. In groups 1, 2, and 3, NaOCl was used with non-activation (NA), passive ultrasonic (PUA), and laser activation (LA). With the same techniques, Ca(OCl)2 was used in groups 4, 5, and 6, and distilled water was used in groups 7, 8, and 9. The weight loss of tissue samples was calculated and analyzed using Two-way ANOVA and Duncan tests. RESULTS: Distilled water groups showed no tissue dissolution in any conditions. NaOCI and Ca(OCI)2 showed statistically similar dissolving effectiveness when used with the same technique. Activated groups dissolved significantly greater tissue than non-activated ones, the highest in LA. CONCLUSIONS: Ca(OCI)2 can be an alternative to NaOCl; for both, the first choice of activation may be the LA.

Machine Learning and Imputation to Characterize Human Norovirus Genotype Susceptibility to Sodium Hypochlorite.

Human norovirus (HuNoV) is the leading cause of foodborne illness in the developed world and a major contributor to gastroenteritis globally. Its low infectious dose and environmental persistence necessitate effective disinfection protocols. Sodium hypochlorite (NaOCl) bleach is a widely used disinfectant for controlling HuNoV transmission via contaminated fomites. This study aimed to evaluate the susceptibility of HuNoV genotypes (n = 11) from genogroups I, II, and IV to NaOCl in suspension. HuNoV was incubated for 1 and 5 min in diethyl pyrocarbonate (DEPC) treated water containing 50 ppm, 100 ppm, or 150 ppm NaOCl, buffered to maintain a pH between 7.0 and 7.5. Neutralization was achieved by a tenfold dilution into 100% fetal bovine serum. RNase pre-treatment followed by RT-qPCR was used to distinguish between infectious and non-infectious HuNoV. Statistical methods, including imputation, machine learning, and generalized linear models, were applied to process and analyze the data. Results showed that NaOCl reduced viral loads across all genotypes, though efficacy varied. Genotypes GI.1, GII.4 New Orleans, and GII.4 Sydney were the least susceptible, while GII.6 and GII.13 were the most susceptible. All NaOCl concentrations above 0 ppm were statistically indistinguishable, and exposure duration did not significantly affect HuNoV reduction, suggesting rapid inactivation at effective concentrations. For instance, some genotypes were completely inactivated within 1 min, rendering extended exposure unnecessary, while other genotypes maintained the initial concentration at both 1 and 5 min, indicating a need for longer contact times. These findings underscore the critical role of HuNoV genotype selection in testing disinfection protocols and optimizing NaOCl concentrations. Understanding HuNoV susceptibility to NaOCl bleach informs better disinfection strategies, aiding public health and food safety authorities in reducing HuNoV transmission and outbreaks.

Color stability and solubility of Biodentine and NeoPutty in contact with different irrigation solutions.

Objectives: This study aimed to evaluate the color stability and solubility of Biodentine and NeoPutty in contact with different irrigation solutions. Materials and Methods: Biodentine and NeoPutty were set in cylindrical molds with 7 mm diameter and 1.5 mm high and immersed in distilled water, 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), 9% 1-hydroxyethylidene 1,1-diphosphonate (HEDP), and 5% sodium hypochlorite (NaOCl) solutions for 24 hours. The color change was measured with a spectrophotometer. The solubility values were calculated as the mass loss was expressed as a percentage of the original mass using an analytical balance with 10-4 g accuracy. Data were analyzed with Kruskal-Wallis followed by Mann-Whitney U tests, and 2-way analysis of variance test followed by Bonferroni corrections for pairwise comparisons for solubility and color stability with a 5% significance threshold, respectively. Results: Biodentine exhibited higher color changes compared to the NeoPutty contact with all solutions except distilled water (p < 0.05). Both hydraulic cements (HCs) showed higher discoloration values immersion in CHX followed by NaOCl. No statistically significant difference was found between Biodentine and NeoPutty regardless of irrigation solution in terms of solubility (p > 0.05). Solubility values were lower in the distilled water group compared to EDTA and CHX (p < 0.05). Conclusions: Tested HCs showed solubility and color changes at various rates. NeoPutty could be an appropriate material in aesthetic areas. The usage of HEDP as an irrigant solution can be considered suitable for various endodontic treatments due to its relatively lower solubility and discoloration values.

In Vitro Evaluation of Sodium Hypochlorite, Chlorhexidine, Propolis, and Calcium Hydroxide Effect on Lipoteichoic-Acid-Induced Proinflammatory Cytokines Production.

This study aimed to evaluate the effects of sodium hypochlorite (NaOCl), chlorhexidine (CHX), and the glycolic extract of propolis (GEP) as endodontic irrigants and of calcium hydroxide [Ca(OH)2], CHX, or Ca(OH)2 + CHX as intracanal medications on the capacity of the lipoteichoic acid (LTA) of Enterococcus faecalis in macrophages' proinflammatory cytokines production. Freshly extracted 108 human single-rooted teeth were used in this study. The LTA of E. faecalis was standardized in double-distilled pyrogen-free water (250 µg/mL) and inoculated into the specimens subdivided into nine subgroups (n = 12). Cultures of murine macrophages (RAW 264.7) were treated with 30 µL of each sample collected from root canals and incubated (37 °C, 5% CO2) for 24 h. Lastly, anti-TNF-α, anti-IL-6, anti-IP-10, anti-MIP-1α, anti-G-CSF, and anti-IL-1ß DuoSet kits were used to perform an ELISA assay. Data were analyzed using one-way ANOVA and Tukey test (p ≥ 0.05). It was found that 1% NaOCl was the most effective irrigant in reducing the capacity of LTA in cytokines production, followed by 12% GEP and 2% CHX, respectively. Ca(OH)2 + CHX presented the best results when associated with NaOCl or GEP. Thus, NaOCl or GEP associated with Ca(OH)2 + CHX were effective in reducing the capacity of LTA in different macrophages pro-inflammatory cytokines production.

In Vitro Bond Strength of Dentin Treated with Sodium Hypochlorite: Effects of Antioxidant Solutions.

This systematic review aims to evaluate whether the application of antioxidant solutions can enhance the bond strength of resin-based materials to sodium hypochlorite (NaOCl)-treated dentin. This study follows the PICOT strategy: population (sodium hypochlorite-treated dentin), intervention (application of antioxidants), control (distilled water), outcome (bond strength), and type of studies (in vitro studies). The systematic review and meta-analysis were conducted following PRISMA guidelines. Electronic databases were searched for in vitro studies evaluating the effects of antioxidants on bond strength to sodium hypochlorite-treated dentin. Two independent reviewers screened articles, extracted data, and assessed risk of bias. Meta-analyses were performed using a random-effects model to compare standardized mean differences in bond strength between antioxidant pretreatment and control groups. Inclusion criteria consisted of in vitro studies that examined the bond strength of resin-based materials to NaOCl-treated dentin with antioxidant application, while exclusion criteria included studies with incomplete data, those not using a control group, or those that did not directly measure bond strength. From 3041 initial records, 29 studies were included in the qualitative analysis and 25 in the meta-analysis. Ascorbic acid, sodium ascorbate, grape seed extract, green tea, and rosmarinic acid significantly improved bond strength to sodium hypochlorite-treated dentin (p < 0.05). The effectiveness of grape seed extract varied with adhesive system type. Hesperidin, p-toluene sulfonic acid, and sodium thiosulfate did not significantly improve bond strength. Most studies had a high risk of bias. This suggests that the conclusions drawn from these studies should be interpreted with caution, and further research with more robust methodologies may be needed to confirm the findings. In conclusion, this systematic review implies that certain antioxidants can improve bond strength to sodium hypochlorite-treated dentin, with efficacy depending on the specific agent and adhesive system used. Further standardized studies are needed to optimize protocols and confirm these findings.

Coaggregation dynamics in drinking water biofilms and implications for chlorine disinfection.

Biofilms in drinking water (DW) systems persistently challenge traditional disinfection methods due to intricate microbial interactions, with coaggregation playing a crucial role in forming multispecies biofilms. This study examined the implications of coaggregation on tolerance towards sodium hypochlorite (NaOCl) disinfection. Dual-species biofilms were formed for seven days on polyvinyl chloride coupons, comprising a strain of the emerging pathogen Stenotrophomonas maltophilia and the coaggregating strain Delftia acidovorans 005 P. For comparison, dual-species biofilms were also formed with a non-coaggregation strain (D. acidovorans 009 P). The minimum bactericidal concentration (MBC) for each planktonic strain varied (D. acidovorans: 1 mg/L, S. maltophilia: 1.5 mg/L) below the safe DW treatment limits. However, high NaOCl doses (10 ×MBC and 100 ×MBC,) showed low efficacy against dual-species biofilms, indicating significant biofilm tolerance to disinfection. Membrane damage occurred at sub-MBC without culturability loss, underscoring biofilm resilience. The biofilm analysis revealed a complex interplay between the composition of extracellular polymeric substances and the architecture, which was influenced by the presence of the coaggregating strain. Overall, coaggregation significantly influenced biofilm formation and resilience, impacting NaOCl disinfection. These findings underscore the challenges of microbial interactions in biofilms, emphasizing the need for improved disinfection strategies to control biofilms in drinking water systems.

Effect of Active Oxygen Fluid (Blue®m) as a Root Canal Irrigant Against Enterococcus Faecalis.

PURPOSE: To evaluate the antimicrobial effect of a new active oxygen fluid (Blue®m) as a root canal irrigant against Enterococcus faecalis compared to sodium hypochlorite (NaOCl). MATERIAL AND METHODS: Forty-five extracted single-canaled human teeth were selected, received root canal preparation, autoclaved, and contaminated with Enterococcus faecalis. The specimens were randomly allocated into three groups: Group (A) served as the negative control, receiving irrigation with saline (n = 15); Group (B) was irrigated with 5.25% NaOCl (n = 15); and Group (C) was irrigated with 10 mL of Blue®m (n = 15). Microbial sampling from the root canals was performed before and after irrigation. The difference between the pre-irrigation and post-irrigation colony-forming units (CFU/mL) was calculated. The data was analysed using a one-way ANOVA followed by post-hoc Tukey tests. The significance level was set at 5%. RESULTS: Blue®m statistically significantly reduced the bacterial load compared to saline (p = 0.009), but NaOCl was most effective, outperforming both (p 0.0001). CONCLUSION: Irrigation with Blue®m demonstrated antibacterial efficacy against Enterococcus faecalis, but it was not as effective as NaOCl.

Exploring Efficacy and Safety: Comparative Evaluation of Different Irrigation Solutions in Root Canal Therapy at a Tertiary Care Setting.

Background: In order to completely remove bacteria and debris from the root canal system, root canal treatment (RCT) calls for efficient irrigation methods. There is still a lack of research on the relative safety and efficacy of various irrigation systems in tertiary care settings. Methods: Patients receiving RCT at a tertiary care endodontic clinic were included in a prospective comparison research of 150 subjects. One of four irrigation solutions-sodium hypochlorite, chlorhexidine, ethylenediaminetetraacetic acid (EDTA), or a combination of the three-was given to patients at random. Following surgery, microbial decrease and patient-reported pain levels were evaluated. Results: The analysis showed that there were significant differences (P < 0.05) in microbial decrease between the irrigation solution groups. EDTA, sodium hypochlorite, and chlorhexidine were the next three groups with the biggest mean log decrease in microbial counts, after the combination group. Nonetheless, there were no appreciable variations in the groups' patient-reported pain levels (P > 0.05). Conclusion: Our results imply that microbial reduction in RCT is highly influenced by the irrigation solution selection. Without having an impact on the pain sensations reported by the patients, the combination of irrigation solutions showed higher efficacy in microbial control. These findings highlight how crucial it is to choose an irrigation solution carefully in order to maximize endodontic outcomes in tertiary care settings.

Non-surgical treatment of residual periodontal pockets using sodium hypochlorite/amino acid gel and cross-linked hyaluronic acid-a 9-month pilot randomized controlled clinical trial.

OBJECTIVES: This pilot randomized controlled clinical trial compares the clinical outcome obtained in persistent periodontal pockets during 9-month follow-up of supportive periodontal step 4 treatment performed by either combining subgingival instrumentation with adjunctively used sodium hypochlorite/amino acid gel and crosslinked hyaluronic acid (xHyA) or subgingival instrumentation alone. MATERIALS AND METHODS: Study protocol is registered under NCT06438354 at Clinicaltrials.gov. Patients seeking further therapy after completed step 2 non-surgical periodontal treatment underwent either repeated subgingival instrumentation with adjunctive application of sodium hypochlorite/amino acid gel and crosslinked hyaluronic acid (group A) or repeated subgingival instrumentation alone (group B). One calibrated investigator performed the treatment sequence in both groups accordingly. Subgingival instrumentation of the residual pockets was carried out under local anaesthesia using hand- and ultrasonic instruments, as well as air polishing in both groups. Patients were instructed to continue oral hygiene without any restriction. At 3-month re-evaluation treatment was repeated accordingly at sites with persistent 5 mm probing depth and BoP + . Clinical attachment level (CAL), pocket probing depth (PPD), gingival recession (GR), and bleeding on probing (BoP) were recorded at baseline (T1), 3- (T2) and 9-month (T3) post-op, with CAL as a primary outcome measure. RESULTS: In total 52 patients (20 females and 32 males, mean age 58.4 ± 2.4 years) presenting with 1448 sites which required further periodontal treatment were enrolled. Both groups exhibited homogeneity in terms of age, gender, smoking habit, initial number of sites, and BOP. At 9-month evaluation, PD reduction and CAL gain showed significant differences between the test and control group, favouring the adjunctive treatment. GR tended to exhibit more recovery in the test group compared to the control group. Although BOP frequency effectively reduced in both groups, there was no statistically significant difference between the two groups. CONCLUSION: Within the limits of the study, the present data indicates that, during subgingival instrumentation of persistent pockets, the adjunctive usage of sodium hypochlorite/amino acid gel and xHyA sufficiently improves the clinical outcomes. The continuous improvement of CAL in association with the GR scores observed in group A, indicates that sites subjected to adjunctive treatment may indicate a tendency for a regenerative response to treatment within the 9-month follow-up period.

Comparative Evaluation of the Effect of Microwave, 1% Sodium Hypochlorite, and Sodium Perborate Disinfection on the Color Stability of Two Nanoparticle-Reinforced Heat-Polymerized PMMA Denture Base Resins: An In Vitro Study.

Introduction Older adults experience significant improvement in their quality of life by using removable prosthetics to replace missing teeth. Poly(methyl methacrylate) (PMMA) has become the most popular material for denture bases due to its ease of use and affordability. Recently, scientists have started adding nanoparticles like titanium dioxide (TiO2) and zirconium oxide (ZrO2) to PMMA to enhance its physical properties. These resins with nanoparticles need to stay the same color after being disinfected in different ways if they are going to be used for a long time. So, the purpose of this investigation was to assess whether or not there exists any difference between two kinds of thermally cured acrylic resin for artificial tooth bases strengthened with nanoparticles when subjected to various chemical sterilizers alongside microwave irradiation, as well as determine their comparative colorfastness levels.  Materials and methods In this lab experiment, we tested how well 5% TiO2 and 7% ZrO2 nanoparticle-reinforced PMMA resins held their color when exposed to microwave irradiation, 1% sodium hypochlorite, or sodium perborate disinfection. We made 120 specimens shaped like discs; half were treated using one method, while the other half were treated using a different method. Color was measured at baseline (T0), after one cycle (T1), after five cycles (T2), and after six months (T3) using a reflectance spectrophotometer, which calculates the color difference (∆E). Results All three methods of disinfection caused significant color changes (p<0.001); however, sodium perborate caused the least amount of change, followed by 1% sodium hypochlorite and microwave irradiation. The mean ∆E values showed that after one day, there was a change in color by 1.1 due to microwave disinfection, which increased to 5.7 after five days; on the other hand, for 1% sodium hypochlorite, the change was recorded as 0.7 after one month and 1.6 after three months and finally reached up to 2.6 after six months, while sodium perborate showed the least amount of change, with ∆E values recorded as 0.2 after one month, 0.5 after three months, and 0.8 after six months. Conclusion Sodium perborate proved to be the most effective disinfectant for maintaining color stability in 5% TiO2 and 7% ZrO2 nanoparticle-reinforced PMMA resins, thus making it ideal for routine disinfection. Therefore, according to this study, sodium perborate should be used as a disinfection method because it results in minimal color change in nanoparticle-reinforced PMMA dentures.

Comparative Analysis of Antimicrobial Properties and Physical Properties of Mineral Trioxide Aggregate Mixed With Distilled Water, Chlorhexidine, and Sodium Hypochlorite Solutions: An In Vitro Study.

BACKGROUND:  Endodontics widely uses mineral trioxide aggregate (MTA) because of its excellent sealing ability, biocompatibility, and capacity to promote healing. However, the effectiveness of MTA can vary depending on the blending solution used. Endodontics commonly employ chlorhexidine (CHX) and sodium hypochlorite (NaOCl), but their impact on MTA's properties necessitates further investigation. MATERIALS AND METHODS: We blended MTA with the specified solutions and prepared it for testing according to the manufacturer's instructions. The study was divided into four groups: group 1 involved MTA blended with distilled water, group 2 consisted of MTA blended with 0.12% CHX solution (PerioGard, Colgate-Palmolive, Osasco, Brazil), group 3 included MTA blended with 0.2% CHX solution (Corsodyl, GlaxoSmithKline Consumer Healthcare, England, UK), and group 4 comprised MTA blended with 5% NaOCl (Azure Research Lab Pvt. Ltd., New Delhi, India). The antimicrobial activity of each group was assessed using the agar diffusion method against Enterococcus faecalis, Candida albicans, and Streptococcus mutans. We measured the compressive strength at 1, 3, 7, and 21 days using an Instron universal testing machine (Hounsfield Test Equipment, Redhill, UK). Statistical significance was evaluated through one-way ANOVA and Kruskal-Wallis tests, with p values <0.05 considered significant. RESULTS:  Group 3 (MTA blended with 0.2% CHX) exhibited the highest antimicrobial efficacy, with significantly larger inhibition zones against Enterococcus faecalis (25.25 ± 0.21 mm vs. 13.33 ± 0.12 mm, p = 0.011), Candida albicans (29.58 ± 0.24 mm vs. 16.97 ± 0.16 mm, p = 0.004), and S. mutans (26.37 ± 0.15 mm vs. 14.55 ± 0.25 mm, p = 0.027). Group 4 (MTA blended with 5% NaOCl) showed the highest compressive strength at one and three days (p = 0.032 and p = 0.021, respectively), but by 21 days, group 2 demonstrated the greatest compressive strength (p = 0.044). CONCLUSION:  MTA mixed with 0.2% CHX provides superior antimicrobial properties, making it suitable for enhanced microbial control in endodontic treatments. Conversely, MTA mixed with 0.12% CHX offers optimal long-term compressive strength. These findings guide selecting MTA formulations to maximize performance based on clinical needs.

Cytotoxic Effect of Two Different Concentrations of Sodium Hypochlorite: An In-Vitro Study.

Introduction The endodontic treatment of primary teeth presents considerable complications due to their distinct anatomical properties. In order to achieve a successful endodontic treatment, certain factors must be assessed. These factors include a precise diagnosis, thorough cleaning, and a reliable disinfection protocol. Although sodium hypochlorite (NaOCl) has been effective as an irrigation agent in primary teeth, it is important to recognize that higher concentrations of NaOCl might possibly inflict toxic harm on the periapical environment if they penetrate the tooth's apical foramina. Since primary teeth are important, pediatric dentists must choose an appropriate NaOCl concentration for root canal irrigation, as higher concentrations can be toxic. Thus, the current investigation examined the cytotoxicity of two different NaOCl concentrations at various volumes. Methods To evaluate the cytotoxicity potential, a culture of nauplii (brine shrimp) was prepared and subjected to testing. For the test, 5, 10, 20, and 40 µL of 1% and 3% NaOCl were added to the brine shrimp culture at different concentrations, and saline was used as a control. After a span of 24 hours, the total number of alive nauplii was duly noted. Results After 24 hours, nauplii showed no mortality in the control group. For 1% NaOCl, mortality ranged from 10% to 20% across volumes, with no significant differences (p = 0.193). In contrast, 3% NaOCl caused significantly higher mortality: 20% at 5 µL, 30% at 10 and 20 µL, and 60% at 40 µL (p = 0.007). Tukey's analysis revealed no significant differences for 1% NaOCl (p > 0.05) but significant differences for 3% NaOCl at 40 µL (p < 0.05). Conclusion Based on the results of the present study, it was observed that a 1% NaOCl solution exhibited a lower level of toxicity in comparison to a 3% NaOCl solution. These findings highlight the importance of using lower concentrations of NaOCl for endodontic irrigation in pediatric dentistry to reduce the risk of tissue damage and ensure safer outcomes for young patients.

Lysine and valine weaken antibiotic resistance in Salmonella Typhimurium induced by disinfectant stress.

Disinfectants are widely used in food production and environmental sanitation to prevent illness, but bacteria resistance to these disinfectants and co-resistance to antibiotics pose a threat to public health. This study investigated the impact of commonly used disinfectants on the resistance of Salmonella Typhimurium (ST) to disinfectants and antibiotics, and explored the metabolic mechanisms underlying the resistance changes. The results showed that subinhibitory concentrations of disinfectants had a minor impact on the resistance of ST to four disinfectants. However, chlorine-containing disinfectants stress enhanced bacteria resistance to ampicillin, while quaternary ammonium compounds stress increased resistance to tetracycline and gentamicin. Untargeted metabolomics analysis revealed significant changes in glutathione metabolism and lysine and valine degradation pathways after disinfectant exposure. Specifically, ST activated lysine decarboxylation, leading to a significant decrease in lysine levels after benzalkonium chloride exposure, while valine and leucine degradation pathways were activated by sodium hypochlorite stress. The addition of downregulated L-lysine and L-valine increased the sensitivity of ST to antibiotics, providing further evidence for the findings of metabolomics. This study provides guidance for the proper use of disinfectants in food processing and establishes a strategy based on metabolomics to control antibiotic-resistant bacteria.