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Background: 0.05% Chlorhexidine gluconate (CHG; Irrisept [IrriMax]) is a commercial wound irrigation solution approved by the Food and Drug Administration that has seen recent adoption in the field of prosthetic urology; however, no study has evaluated whether 0.05% CHG is compatible with the minocycline-rifampin-impregnated surface (InhibiZone) of the AMS 700 penile prosthesis (Boston Scientific)., Aim: To evaluate whether 0.05% CHG alters the antibiotic efficacy of the minocycline-rifampin-impregnated penile prosthesis surface., Methods: Discs (8 mm) were taken by a punch biopsy (Sklar) from sterile penile prosthesis reservoirs whose surfaces had been impregnated with rifampin and minocycline. Discs (n = 10) were suspended in 0.05% CHG, vancomycin and gentamicin, or normal saline for 2 minutes to simulate intraoperative irrigation. Discs were then rinsed in normal saline to remove any unbound solution and incubated with methicillin-sensitive Staphylococcus aureus for 48 hours. Adherent surface bacteria were suspended by shaking in a 0.3% Tween 20 solution, serially diluted, plated onto 3M PetriFilms, and counted. Kirby-Bauer disc diffusion assays were conducted to generalize findings across various organisms., Outcomes: Outcomes included (1) bacterial adherence to the implant surface measured as bacterial counts (in colony-forming units per milliliter) and (2) bacterial growth reduction measured as zones of inhibitions (in millimeters)., Results: Incubation of implant surfaces in 0.05% CHG did not alter recovered bacterial counts as compared with normal saline and vancomycin/gentamycin. Similarly, within a single bacterial species, 0.05% CHG and vancomycin/gentamycin did not alter zone-of-inhibition measurements in Kirby-Bauer disc diffusion studies., Clinical Translation: This study demonstrates in vitro that 0.05% CHG may be used directly on the minocycline-rifampin-impregnated surface without altering the antibiotic efficacy of the coating., Strengths and Limitations: Strengths include that this is the first study to evaluate if 0.05% CHG affected the minocycline-rifampin-impregnated surface. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate or translatable in a clinical setting., Conclusion: 0.05% CHG does not alter the antimicrobial activity of the minocycline-rifampin-impregnated surface as compared with vancomycin/gentamycin and normal saline in vitro; however, its efficacy in clinical practice remains to be evaluated., (© The Author(s) 2024. Published by Oxford University Press on behalf of The International Society of Sexual Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Chlorhexidine gluconate (CHG) (0.05%) has recently been suggested as both a dip for the hydrophilic surface and an irrigation solution in the setting of penile prosthesis (PP) surgery., Aim: The study sought to compare the antimicrobial efficacy of 0.05% CHG with vancomycin and gentamicin (VG) antibiotics as dip and/or irrigation solutions in the setting of a hydrophilic PP surface in vitro., Methods: Sterile PPs with a hydrophilic coating were obtained. A series of experiments were performed to evaluate the efficacy of normal saline (NS), 0.05% CHG, or VG as dip and/or irrigation solutions to reduce methicillin-sensitive Staphylococcus aureus adhesion to PP surfaces. The 8-mm discs from PPs were incubated in 105 colony-forming units/mL of methicillin-sensitive S aureus for 48 hours, plated, and counted. Disc-diffusion tests were conducted by suspending 6-mm discs for 2 minutes in NS, 0.05% CHG, or VG, then placing them coated side down onto plates streaked with the following organisms: methicillin-sensitive S aureus, S epidermidis, Enterococcus, and Escherichia coli. After 24 hours of growth, zones of inhibition were measured., Outcomes: We found average bacterial counts (colony-forming units/mL) and zones of inhibition (mm) following a series of treatment protocols of PP discs., Results: PP discs dipped in VG reduced bacterial adhesion to the implant surface >0.05% CHG (~5.5 log vs ~1.5 log; P < .01). Discs irrigated with either 0.05% CHG or NS removed all dip solution adsorbed to the hydrophilic surface, allowing bacterial growth. VG irrigation adsorbed to the hydrophilic surface even after 0.05% CHG or NS dips, reducing bacterial adherence (~3 log). Dipping and irrigating discs with VG was most effective in reducing adherent bacteria (~5.5 log) and was the only irrigation that showed antimicrobial activity., Clinical Translation: VG, when used both as a prophylactic dip and as an intraoperative irrigation solution for hydrophilic penile implant surfaces, has improved efficacy to 0.05% CHG and NS., Strengths and Limitations: This is the first study to compare the use of VG, 0.05% CHG, and NS as prophylactic dips and intraoperative irrigations for hydrophilic penile implant surfaces. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate nor translatable clinically., Conclusion: We demonstrated the superior efficacy of VG as a combined dip and irrigation solution for hydrophilic penile implant surfaces compared with 0.05% CHG., (© The Author(s) 2024. Published by Oxford University Press on behalf of The International Society of Sexual Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Chlorhexidine gluconate (CHG) and povidone-iodine (PI) are commonly used to prevent prosthetic joint infection (PJI) during total joint replacement; however, their effective concentrations and impact on biofilms are not well defined., Aim: To determine: (1) the in-vitro minimum inhibitory concentration of CHG and PI against model PJI-causing organisms and clinical isolates; (2) their impact on biofilm formation; (3) whether there is a synergistic benefit to combining the two solutions; and (4) whether adding the antibiotic vancomycin impacts antiseptic activity., Methods: We measured in-vitro growth and biofilm formation of Staphylococcus epidermidis, meticillin-sensitive and meticillin-resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, as well as recent clinical isolates, in the presence of increasing concentrations of CHG and/or PI. Checkerboard assays were used to measure potential synergy of the solutions together and with vancomycin., Findings: CHG and PI inhibited growth and biofilm formation of all model organisms tested at concentrations of 0.0004% and 0.33% or lower, respectively; highly dilute concentrations paradoxically increased biofilm formation. The solutions did not synergize with one another and acted independently of vancomycin., Conclusion: CHG and PI are effective at lower concentrations than typically used, establishing baselines to support further clinical trials aimed at optimizing wound disinfection. There is no synergistic advantage to using both in combination. Vancomycin is effective at inhibiting the growth of S. epidermidis and S. aureus; however, it stimulates P. aeruginosa biofilm production, suggesting in the rare case of P. aeruginosa PJI, it could exacerbate infection., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Shoulder periprosthetic joint infection is most commonly caused by Cutibacterium. Effective removal of these bacteria from the skin is difficult because Cutibacterium live protected in the dermal sebaceous glands beneath the skin surface to which surgical preparation solutions, such as chlorhexidine gluconate (CHG), are applied. There is conflicting evidence on the additional benefit of using hydrogen peroxide (H2O2) as an adjunct to CHG in eliminating Cutibacterium from the skin. A previous study demonstrated that after CHG skin preparation, repopulation of Cutibacterium from sebaceous glands onto the skin surface occurs in 90% of shoulders by 60 minutes after application. The objective of this randomized controlled study was to determine the effectiveness of adding H2O2 to CHG in reducing skin Cutibacterium., Methods: Eighteen male volunteers (36 shoulders) were recruited for this study. The 2 shoulders of each volunteer were randomized to receive the control preparation ("CHG-only" - 2% CHG in 70% isopropyl alcohol alone) or the study preparation ("H2O2+CHG" - 3% H2O2 followed by 2% CHG in 70% isopropyl alcohol). Skin swabs were taken from each shoulder prior to skin preparation and again at 60 minutes after preparation. Swabs were cultured for Cutibacterium and observed for 14 days. Cutibacterium skin load was reported using a semiquantitative system based on the number of quadrants growing on the culture plate., Results: Prior to skin preparation, 100% of the CHG-only shoulders and 100% of the H2O2+CHG shoulders had positive skin surface cultures for Cutibacterium. Repopulation of Cutibacterium on the skin at 60 minutes occurred in 78% of CHG-only and 78% of H2O2+CHG shoulders (P = 1.00). Reduction of Cutibacterium skin levels occurred in 56% of CHG-only and 61% of H2O2+CHG shoulders (P = .735). Cutibacterium levels were significantly decreased from before skin preparation to 60 minutes after preparation in both the CHG-only (2.1 ± 0.8 to 1.3 ± 0.9, P = .003) and the H2O2+CHG groups (2.2 ± 0.7 to 1.4 ± 0.9, P < .001). Substantial skin surface levels of Cutibacterium were present at 60 minutes after both preparations., Conclusions: In this randomized controlled study, there was no additional benefit of using hydrogen peroxide as an adjunct to chlorhexidine gluconate skin preparation in the reduction of cutaneous Cutibacterium levels. Neither preparation was able to eliminate repopulation of Cutibacterium on the skin surface from the dermal sebaceous glands., (Copyright © 2024 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

The purpose of this study was to evaluate the antibacterial effect of silver nanoparticles (AgNPs) against Enterococcus faecalis and compare it with different irrigation solutions. This study was performed using 64 dentin blocks. E. faecalis suspension was dispensed to each sample and incubated under anaerobic conditions at 37°C throughout 21 days. After the inoculation period, the following solutions were added to each group and kept for 5 min: Group 1, 5.25% sodium hypochlorite (NaOCl); Group 2, 2.5% NaOCl; Group 3, 1% NaOCl; Group 4, 2% chlorhexidine (CHX); Group 5, 200 ppm hypochlorous acid (HOCl); and Group 6, AgNPs. The samples of positive control were treated with sterile saline. Biofilm viability assay was performed using the LIVE/DEAD BacLight Bacterial Viability Kit. Samples were examined using confocal laser scanning microscopy, respectively. There was no significant difference between the 5.25% NaOCl, 2.5% NaOCl, and 1%NaOCl groups (p > .05). However, these groups showed statistically higher antibacterial activity than the 2% CHX, 200 ppm HOCl, and AgNP groups. Also, 2% CHX showed greater percentage of dead cells compared with the AgNP and HOCl groups. While AgNPs group showed lower dead cell rate than all NaOCl groups and 2% CHX, it caused higher dead cells than 200 ppm HOCl group. The 200 ppm HOCl group showed the lowest percentage of dead cells (p < .05) Although the antibacterial effect of AgNPs is not as high as NaOCl and CHX, it has considerable bactericidal activity against E. faecalis and can be improved by further studies. RESEARCH HIGHLIGHTS: New antimicrobial approaches for root canal irrigation. Antimicrobial effect of silver nanoparticles against E. faecalis. Elimination of the biofilm layer for the success of endodontic treatment., (© 2024 The Authors. Microscopy Research and Technique published by Wiley Periodicals LLC.)

To assess the biochemical, mechanical and structural characteristics of retained dentin after applying three novel bromelain-contained chemomechanical caries removal (CMCR) formulations in comparison to the conventional excavation methods (hand and rotary) and a commercial papain-contained gel (Brix 3000). Seventy-two extracted permanent molars with natural occlusal carious lesions (score > 4 following the International Caries Detection and Assessment System (ICDAS-II)) were randomly allocated into six groups (n = 12) according to the excavation methods: hand excavation, rotary excavation, Brix 3000, bromelain-contained gel (F1), bromelain-chloramine-T (F2), and bromelain-chlorhexidine gel (F3). The superficial and deeper layers of residual dentin were examined by Raman microspectroscopy and Vickers microhardness, while the surface morphology was assessed by the scanning electron microscope (SEM). A multivariate analysis of variance followed by Tukey's test (p > 0.05) was performed for data analysis. The novel formulations showed an ability to preserve the partially demineralized dentin that showed a reduced phosphate content with a higher organic matrix. This was associated with lower Vickers microhardness values in comparison to sound dentin and rotary excavation. The collagen integration ratio in all methods was close to sound dentin (0.9-1.0) at the deeper dentin layer. The bromelain-chloramine-T gel (F2) produced the smoothest smear-free dentin surface with a higher number of opened dentinal tubules. In contrast, dense smearing covering the remaining dentin was observed in the manual and rotary methods with obstructed dentin tubule orifices. The bromelain-contained formulations can be considered a new minimally invasive approach for selectively removing caries in deep cavitated dentin lesions., (© 2024. The Author(s).)

Worldwide, synthetic compounds are used for both in-office and at-home dental care. They are a valuable resource for both prophylactic and curative treatments for various dental problems, such as tooth decay, periodontal diseases, and many more. They are typically preferred due to their broad range of actions and ability to produce targeted, rapid, and long-lasting effects. Using a 0.12% chlorhexidine mouthwash is capable of reducing the plaque index from 47.69% to 2.37% and the bleeding index from 32.93% to 6.28% after just 2 weeks. Mouthwash with 0.1% OCT is also highly effective, as it significantly lowered the median plaque index and salivary bacterial counts in 152 patients in 5 days compared to a control group ( p < 0.0001), while also reducing the gingival index ( p < 0.001). When povidone-iodine was used as an irrigant during the surgical removal of mandibular third molars in 105 patients, it resulted in notably lower pain scores after 2 days compared to a control group (4.57 ± 0.60 vs. 5.71 ± 0.45). Sodium hypochlorite is excellent for root canal disinfection, as irrigating with 1% NaOCl completely eliminated the bacteria from canals in 65% patients. A 0.05% CPC mouthwash proved effective for perioperative patient care, significantly decreasing gingival bleeding ( p < 0.001) and suppressing Streptococcus levels even one week post-surgery. Lastly, a 6% H2O2 paint-on varnish and 6% H2O2 tray formulations successfully bleached the teeth of 40 patients, maintaining a noticeably whiter appearance up to the 6-month follow-up, with significant color differences from the baseline ( p < 0.005). Synthetic compounds have a large research base, which also provides a greater awareness of their mechanism of action and potential adverse effects. For a better understanding of how they work, several methods and assays are performed. These are protocolary techniques through which a compound's efficacy and toxicity are established.

Purpose: To investigate the stain preventing ability of a new chlorhexidine mouthwash while maintaining efficacy using a randomized clinical trial design., Methods: 98 subjects were enrolled and completed a 4-week clinical study that evaluated the effectiveness of the new mouthwash on plaque, gingivitis, and staining as compared to a commercially available chlorhexidine mouthwash. A subset of 62 subjects was evaluated for the effectiveness of the mouthwashes against plaque bacteria., Results: After 4 weeks of use, the new chlorhexidine mouthwash reduced staining by 42.6% (P< 0.05) as compared to the commercially available mouthwash. The two mouthwashes were equivalent with regards to their effect on gingivitis, plaque, and plaque bacteria., Clinical Significance: A new mouthwash, containing 0.12% chlorhexidine gluconate, has been developed that delivers stain reduction while maintaining equivalent efficacy to a commercially available chlorhexidine mouthwash with regards to gingivitis, plaque, and plaque bacteria. These findings should be considered by dental practitioners when making recommendations to patients whose teeth stain easily and need an anti-gingivitis and anti-plaque mouthwash., Competing Interests: Dr. Tang, R. Ahmed, Dr. Daep, Dr Stranick, Dr. Mello, Dr. Won, Dr. Pimenta, Dr. Zhang, and Dr. Sreenivasan, were employees of Colgate-Palmolive Company when the research was conducted. Colgate-Palmolive Company funded the research. The clinical study was conducted completely under the supervision of employees of Rutgers University. Dr. Fine, D. Tischio-Bereski, and D. Godboley are employed by Rutgers University and declared no conflict of interest. Dr. Fine had the final word on all aspects of the analysis, interpretation, and the written manuscript., (Copyright©American Journal of Dentistry.)

Introduction . The global spread of Acinetobacter spp., particularly the Acinetobacter calcoaceticusbaumannii (ACB) complex, has led to its recognition as a significant pathogen by the World Health Organization (WHO). The increasing resistance of the ACB complex to multiple antibiotics presents a challenge for treatment, necessitating accurate antibiotic susceptibility profiling after isolation. Hypothesis or gap statement . There is limited understanding of the antimicrobial resistance and chlorhexidine, a biocide, susceptibility profiles of ACB complex strains, especially in clinical settings in Turkey. Aim . This study aimed to identify ACB complex strains recovered from various clinical specimens at Hacettepe University Hospitals in Ankara, Turkey, in 2019, and to assess identification, their antibiotic and chlorhexidine susceptibility profiles, and genomic relatedness. Methodology . Eighty-two ACB complex strains were identified using MALDI-TOF MS. Susceptibility testing to 12 antibiotics was conducted using the disc diffusion method, and colistin, chlorhexidine susceptibility was assessed using the broth microdilution technique, following the latest EUCAST and CLSI guidelines. ACB complex members with reduced chlorhexidine sensitivity were further analyzed by pulsed-field gel electrophoresis (PFGE) for bacterial typing. Results . Among the isolates, 1.2% were multidrug-resistant (MDR), 73.2% were extensively drug-resistant (XDR), and 12.2% were pandrug-resistant (PDR). Carbapenem resistance was found in 86.7% of MDR, PDR, and XDR strains. Colistin resistance was observed in 15.8% of isolates, and 18.2% exhibited decreased susceptibility to chlorhexidine. PFGE revealed seven different clones among strains with reduced chlorhexidine sensitivity, indicating vertical transmission within the hospital. Conclusion . This study highlights the reduced susceptibility to chlorhexidine in ACB complex members and provides epidemiological insights into their spread. The findings underscore the importance of screening for antimicrobial resistance and biocide susceptibility profiles to effectively manage healthcare-associated infections.

This study aimed to evaluate the interface of universal adhesive (UA) with bulk-fill resin (BF) and dentin, after endodontic irrigation. The pulp chamber of 96 molars was irrigated with chlorhexidine 2% (CHX) or sodium hypochlorite 5.25% (NaOCl) and restored according to three restorative protocols. Microtensile bond strength (μTBS) and nanoleakage tests were performed after 24 h of thermocycling. Kruskal Wallis, Mann-Whitney and Wilcoxon were performed (p < 0.05). Comparing restorative systems, a difference was found only when irrigated with CHX after 24 h. CHX provided higher μTBS than NaOCl after 24 h for two restorative protocols; after thermocycling, NaOCl provided the greatest μTBS than CHX for one group. Decreased μTBS was observed for all restorative systems when CHX was used after thermocycling. NaOCl demonstrated the highest nanoleakage. The composition of UA influenced the immediate adhesion and sealing to BF when CHX was used; ageing has a deteriorating effect on adhesion and sealing for all restorative systems., (© 2024 Australian Society of Endodontology Inc.)

Objective: The effectiveness of supragingival dental biofilm control during orthodontic treatment and changes in the bacterial profile were analyzed., Design: Sixty-four participants aged 12-22 years (57% female) were included in the study. Participants underwent orthodontic treatment with fixed appliances and were randomly assigned to one of the three groups, which during a period of one month: (I) used chlorhexidine digluconate (CHX), (II) used high concentration of fluoride (F) gel and (III) performed standard oral hygiene. The plaque and gingivitis index, pH of biofilm and white spot lesions (WSL) were assessed. Changes of the bacteria in the biofilm were analyzed by the quantitative polymerase chain reaction RESULTS: Increase in the plaque index, pH of biofilm, and WSL was observed during orthodontic treatment with standard oral hygiene. Large interindividual variability was present, and the effects of one-month use of fluorides and CHX on clinical parameters were not significant. Despite standard hygiene the abundance of studied biofilm bacteria increased - the most Streptoccocus mutans (14.2x) and S. salivarius (3.3x), moderate Veillonella parvula (3x) and the least S. sobrinus (2.3x) and Agregatibacter actinomycetemcomitans (1.9x). The use of CHX reduced S. sobrinus (2.2x) and A. actinomycetemcomitans (1.9x). Fluoride use reduced A. actinomycetemcomitans (1.3x) and S. sobrinus (1.2x). Fluorides better controlled S. mutans than CHX., Conclusion: Bacterial biomass in supragingival biofilm increased during treatment with metal orthodontic appliances, with greater increase in cariogenic bacteria than periopathogens. Fluoride controlled S. mutans, while CHX S. sobrinus and A. actinomycetemcomitans., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Introduction: This study aimed to assess BioRoot RCS (BR) incorporating liposomal chlorhexidine digluconate (CHX) for its antibacterial activity, drug release capacity, and physicochemical properties., Methods: Drug release of CHX liposomal formulations in combination with BR was evaluated spectrophotometrically and through mathematical release models for 30 days. A selected combination was evaluated for antimicrobial properties against Enterococcus faecalis biofilm growth on human dentin. Cytotoxicity was assessed following the ISO 10993-5:2019 standard on days 1, 3, and 7. Physicochemical properties were evaluated through setting time, Fourier transform infrared spectroscopy, solubility, contact angle, and film thickness., Results: From BR, liposomal CHX released up to 7-fold higher CHX than CHX solution (P < .05), following a triphasic drug release pattern compared to the CHX solution, which followed a quasi-Fickian diffusion. BR combined with a selected liposomal CHX completely inhibited E. faecalis biofilm growth compared to the combination of BR with CHX solution and the control group (P < .05). Liposomal CHX decreased the contact angle (P < .05) and solubility but increased cytotoxicity (P < .05) of BR, staying above the ISO threshold. None of the other physicochemical characteristics tested differed from BR (P > .05)., Conclusion: This liposomal formulation improved CHX release from BR, enhancing the antibacterial effectiveness. It presents a promising approach for local antibiofilm therapy in endodontics without substantially altering the physicochemical characteristics of BR., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Polypropylene (PPE) mesh is commonly utilized to reconstruct catastrophic extensor mechanism disruptions in revision total knee arthroplasty. Unfortunately, these procedures are associated with a high rate of periprosthetic joint infection. The purpose of the current study was to: 1) visualize and quantify the progression of bacterial biofilm growth on PPE-mesh; and 2) determine which antiseptic solutions effectively remove viable bacteria., Methods: Knitted PPE mesh samples were cultured with either methicillin-sensitive Staphylococcus aureus (MSSA) or Escherichia coli (E. coli) for 7 days, with regular quantification of colony forming units (CFUs) and visualization using scanning electron microscopy to identify maturity. Immature (24 hour) and mature (72 hour) biofilm was treated with one of 5 commercial antiseptics for 3 minutes. A 0.05% chlorhexidine gluconate, a surfactant-based formulation of ethanol, acetic acid, sodium acetate, benzalkonium chloride, diluted povidone-iodine (0.35%), undiluted (10%) povidone-iodine, and 1:1 combination of 10% povidone-iodine and 3% hydrogen peroxide. A 3-log reduction in CFUs compared to saline was considered clinically meaningful., Results: The CFU counts plateaued, indicating maturity, at 72 hours for both MSSA and E. coli. The scanning electron microscopy confirmed confluent biofilm formation after 72 hours. The 10% povidone-iodine was clinically effective against all MSSA biofilms and immature E. coli biofilms. The 10% povidone-iodine with hydrogen peroxide was effective in all conditions. Only 10% povidone iodine formulations produced significantly (P < .0083) reduced CFU counts against mature biofilms., Conclusions: Bacteria rapidly form biofilm on PPE mesh. Mesh contamination can be catastrophic, and clinicians should consider utilizing an antiseptic solution at the conclusion of mesh implantation. Undiluted povidone-iodine with hydrogen peroxide should be considered when attempting to salvage infected PPE mesh., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objectives: This study aims to evaluate antibacterial effects of silver diamine fluoride (SDF), SDF/potassium iodide (KI), and nanosilver fluoride (NSF)., Methods: Antimicrobial activity of sterile saline, 5% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), SDF, SDF/KI, NSF, and KI solutions against Streptococcus mutans and Lactobacillus casei was assessed through disc diffusion tests. A dual-species biofilm of S. mutans-L. casei was formed on 48 enamel samples, divided into six groups (n = 8). Group 1 was treated with sterile saline, Group 2 with 5% NaOCl, Group 3 with 2% CHX, Group 4 with SDF, Group 5 with SDF/KI, and Group 6 with NSF. The samples were analysed using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Statistical analysis utilized Shapiro-Wilk and Kruskal-Wallis tests and multiple comparisons were conducted using Dunn test., Results: SDF, SDF/KI, and NaOCl displayed significantly higher antibacterial activity against dual-species biofilm compared to NSF and CHX (p < 0.050)., Conclusions: In conclusion, SDF and SDF/KI demonstrated greater antibacterial activity than NSF. SDF's antibacterial activity was unaffected by KI. Further research is needed to determine the appropriate content and concentration for achieving effective antibacterial activity with NSF., Clinical Significance: The use of silver-containing materials is increasing in popularity within pediatric dentistry. In this study, an endeavor has been made to assist pediatric dentists in determining which solution might be more advantageous for preventing caries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Objective: The aim of this scoping review was to explore and synthesise the current evidence on the antimicrobial activity of antibacterial suture materials used in oral surgery., Methods: The review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews. A bibliographic search was carried out in the PubMed and Scopus databases to retrieve all human clinical studies that investigated the antimicrobial efficacy of antibacterial-coated sutures used in oral surgery. Included studies were screened and extracted independently by 2 examiners. Data were tabulated and qualitatively described., Results: The search initially returned 150 articles and resulted in 5 included studies after the duplicates' removal and the full-text screening. Selected studies were published from 2014 to 2019. Three studies (60%) were randomised clinical trials, whilst the remaining studies did not report information on randomisation. The antimicrobial agents for coated sutures included triclosan and chlorhexidine. In almost all the studies, antibacterial-coated sutures exhibited lower bacterial retention compared to those without coating., Conclusions: Within limitations, the antimicrobial-coated sutures employed in oral surgery exhibited good results in terms of their microbicidal activity when compared with sutures that were not coated. Considering the high variability and confounding factors identified in the included studies, more high-quality research is needed to confirm these results. Antimicrobial-coated sutures could represent a promising and clinically valid strategy to reduce microbial colonisation in oral surgery. The reduced bacterial adherence is likely to improve the clinical success of the surgical procedures. Yet, the cost-benefit ratio of antimicrobial-coated sutures should be assessed in larger clinical trials to confirm their efficacy over conventional noncoated sutures., Competing Interests: Conflict of interest None disclosed., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The growing challenge of antibiotic resistance necessitates novel approaches for combating bacterial infections. This study explores the distinctive synergy between chlorhexidine, an antiseptic and disinfectant agent, and azithromycin, a macrolide antibiotic, in their impact on bacterial growth and virulence factors using Escherichia coli strain Crooks (ATCC 8739) as a model. Our findings reveal that the chlorhexidine and azithromycin combination demonstrates enhanced anti-bacterial effects compared to individual treatments. Intriguingly, the combination induced oxidative stress, decreased flagellin expression, impaired bacterial motility, and enhanced bacterial autoaggregation. Notably, the combined treatment also demonstrated a substantial reduction in bacterial adherence to colon epithelial cells and downregulated NF-κB in the epithelial cells. In conclusion, these results shed light on the potential of the chlorhexidine and azithromycin synergy as a compelling strategy to address the rising challenge of antibiotic resistance and may pave the way for innovative therapeutic interventions in tackling bacterial infections., (© 2024. The Author(s).)

Objective: To evaluate the effect of the association of potassium iodide to antimicrobial photodynamic therapy on human carious dentin produced with a microcosm biofilm model., Methods: A microcosm biofilm model was used to generate a caries lesion on human dentin. Pooled human saliva diluted with glycerol was used as an inoculum on specimens immersed on McBain artificial saliva enriched with 1 % sucrose (24 h at 37 °C in 5 % CO 2 ). After refreshing culture media for 7 days, the dentin specimens were divided in 5 groups (3 specimens per group, in triplicate; n = 9): C (NaCl 0.9 %), CX (2 % chlorhexidine), PKI (0.01 % methylene blue photosensitizer+50 mM KI), L (laser at 15 J, 180 s, 22.7 J/cm 2 ), and PKIL (methylene blue + KI + Laser). After the treatments, dentin was collected, and a 10-fold serial dilution was performed. The number of total microorganisms, total lactobacilli, total streptococci, and Streptococcus mutans was analyzed by microbial counts (CFU/mL). After normality and homoscedasticity analysis, the Welch's ANOVA and Dunnett's tests were used for CFU. All tests used a 5 % significance level., Results: CX and PKIL groups showed significant bacterial decontamination of dentin, compared to group C (p < 0.05) reaching reductions up to 3.8 log 10 for CX for all microorganisms' groups and PKIL showed 0.93, 1.30, 1.45, and 1.22 log 10 for total microorganisms, total lactobacilli, total streptococci, and S. mutans, respectively., Conclusion: aPDT mediated by the association of KI and methylene blue with red laser reduced the viability of microorganisms from carious dentin and could be a promising option for cavity decontamination., Competing Interests: Declaration of Competing Interest The authors have no potential conflict of interest to declare., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: This study aimed to synthesize and characterize colloidal chitosan-silver nanoparticles-fluoride nanocomposite (CCAgNPF) and evaluate its efficacy compared to chlorhexidine on salivary Streptococcus mutans in orthodontic patients., Materials and Methods: AgNPs stabilized with chitosan were synthesized by chemical reduction of AgNO 3 . The nanoparticles were characterized with SEM, FTIR, DLS and ICP-OES. The MIC and MBC against S. mutans and IC50 concentration of CCAgNPF were obtained for antibacterial and cytotoxicity evaluations, respectively. For the clinical study, a total of 45 orthodontic patients were divided into three groups of 15 and used the following mouthwashes twice a day for 1 month: CCAgNPF, chlorhexidine 0.2% and the combination of these mouthwashes. The colony count of salivary S. mutans was evaluated before and after using the mouthwashes. The data were analyzed using One-way ANOVA and Tukey's test., Results: Stabilized AgNPs were spherical with a diameter of 25.3 ± 3.3 nm. The MIC, MBC and IC50 of CCAgNPF were 4.42, 8.85 and 18.89 µg/ml. All mouthwashes reduced the salivary S. mutans of the orthodontic patients, however, no significant difference was found between the efficacy of CCAgNPF and chlorhexidine (P-value > 0.05). The best results were achieved by the combination of CCAgNPF and chlorhexidine mouthwashes (P-value < 0.05)., Conclusion: The CCAgNPF and its combination with chlorhexidine present potent bactericidal, biocompatible and effective anti-carious mouthwashes for orthodontic patients., Clinical Relevance: This study proved CCAgNPF as an antibacterial mouthwash with lower cytotoxicity and side effects for patients undergoing orthodontic treatments to maintain oral hygiene and reduce salivary S. mutans., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: This study aimed to investigate the efficiency of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm in the oral cavity using the photosensitizer chloroaluminum phthalocyanine encapsulated in chitosan nanoparticles (ClAlPc/Ch) at three preirradiation times., Methods: Biofilms of Streptococcus mutans strains (ATCC 25,175) were cultivated on bovine tooth blocks and exposed to a 10% sucrose solution three times a day for 1 min over three consecutive days. The samples were randomly distributed into five treatment groups (n = 5): (I) aPDT with ClAlPc/Ch with a preirradiation time of 5 min (F5), (II) aPDT with ClAlPc/Ch with a preirradiation time of 15 min (F15), (III) aPDT with ClAlPc/Ch with a preirradiation time of 30 min (F30), (IV) 0.12% chlorhexidine digluconate (CHX), and (V) 0.9% saline solution (NaCl). After treatment, the S. mutans biofilms formed on each specimen were collected to determine the number of viable bacteria (colony-forming units (CFU)/mL). Data were analyzed for normality using the Shapiro-Wilk test and the analysis of variance (ANOVA) and Tukey HSD tests to analyze the number of viable bacteria (α = 0.05)., Results: The one-way ANOVA showed a difference between the groups (p = 0.0003), and the Tukey HSD posttest showed that CHX had the highest microbial reduction of S. mutans, not statistically different from the F5 and F15 groups, whereas the NaCl group had the lowest microbial reduction statistically similar to the F30 group., Conclusion: The results demonstrate that aPDT mediated by ClAlPc/Ch when used at preirradiation times of 5-15 min can be an effective approach in controlling cariogenic biofilm of S. mutans, being an alternative to 0.12% CHX., (© 2024. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

Candida auris is an emerging fungal pathogen responsible for healthcare-associated infections and outbreaks with high mortality around the world. It readily colonizes the skin, nares, respiratory and urinary tract of hospitalized patients, and such colonization may lead to invasive Candida infection in susceptible patients. However, there is no recommended decolonization protocol for C. auris by international health authorities. The aim of this study is to evaluate the susceptibility of C. auris to commonly used synthetic and natural antiseptic products using an in vitro, broth microdilution assay. Synthetic antiseptics including chlorhexidine, povidone-iodine, and nystatin were shown to be fungicidal against C. auris. Among the natural antiseptics tested, tea tree oil and manuka oil were both fungicidal against C. auris at concentrations less than or equal to 1.25% (v/v). Manuka honey inhibited C. auris at 25% (v/v) concentrations. Among the commercial products tested, manuka body wash and mouthwash were fungicidal against C. auris at concentrations less than or equal to 0.39% (w/v) and 6.25% (v/v) of products as supplied for use, respectively, while tea tree body wash and MedihoneyTM wound gel demonstrated fungistatic properties. In conclusion, this study demonstrated good in vitro antifungal efficacy of tea tree oil, manuka oil, manuka honey, and commercially available antiseptic products containing these active ingredients. Future studies are warranted to evaluate the effectiveness of these antiseptic products in clinical settings., (© The Author(s) 2024. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Aims: We aimed to identify mechanisms underlying the tolerance of Proteus mirabilis-a common cause of catheter associated urinary tract infection-to the clinically used biocides chlorhexidine (CHD) and octenidine (OCT)., Methods and Results: We adapted three clinical isolates to grow at concentrations of 512 µg ml-1 CHD and 128 µg ml-1 OCT. Genetic characterization and complementation studies revealed mutations inactivating the smvR repressor and increasing smvA efflux expression were associated with adaptation to both biocides. Mutations in mipA (encoding the MltA interacting protein) were less prevalent than smvR mutations and only identified in CHD adapted populations. Mutations in the rppA response regulator were exclusive to one adapted isolate and were linked with reduced polymyxin B susceptibility and a predicted gain of function after biocide adaptation. Biocide adaptation had no impact on crystalline biofilm formation., Conclusions: SmvR inactivation is a key mechanism in both CHD and OCT tolerance. MipA inactivation alone confers moderate protection against CHD, and rppA showed no direct role in either CHD or OCT susceptibility., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Background: The probability of a positive outcome of root canal therapy is substantially higher if the infection is eradicated successfully before the obturation of the root canal system. Irrigation is an essential aspect of root canal debridement, as it enables more thorough cleaning than is possible with root canal instrumentation alone. To overcome the side effects of chemical irrigants, there has been a search for herbal medicines as substitutes., Objectives: The aim of the present study was to explore the antimicrobial efficacy of white tea-mediated silver nanoparticles (AgNPs) formulated as an intracanal irrigant against Enterococcus faecalis, and to compare it with the efficacy of chlorhexidine and sodium hypochlorite irrigants., Material and Methods: The experimental groups were as follows: group I - white tea-mediated AgNPs; group II - 2% chlorhexidine; and group III - 2.5% sodium hypochlorite. The characterization of AgNPs was performed using ultraviolet-visible (UV-Vis) spectroscopy and transmission electron microscopy (TEM) analysis. Enterococcus faecalis was inoculated onto Mueller-Hinton agar plates. The disks impregnated with irrigants were placed on the inoculated plates and incubated aerobically at 37°C for 24 h. Then, the growth inhibition zones were measured. Statistical analysis was performed using the one-way analysis of variance (ANOVA) and the post hoc tests., Results: A concentration of 50 μL of white tea-mediated AgNPs exhibited the greatest zone of inhibition (32 ±2 mm), followed by 2% chlorhexidine (25 ±1 mm) and 2.5% sodium hypochlorite (23 ±3 mm)., Conclusions: White tea-mediated AgNPs showed promising results in the elimination of E. faecalis, being superior to chlorhexidine and sodium hypochlorite irrigants.

The purpose of this study was to evaluate the antibacterial efficacy of using 2.5% NaOCl, 2% chlorhexidine (CHX), Irritrol, and chitosan-coated silver nanoparticles (AgCNPs) alone or in combination with deoxyribonuclease I (DNase I) and trypsin pre-enzyme applications in dentin samples contaminated with Enterococcus faecalis (E. faecalis) by CLSM. 144 dentin blocks with confirmed E. faecalis biofilm formation were divided randomly according to the irrigation protocol (n = 12): NaOCl, CHX, Irritrol, AgCNPs, trypsin before NaOCl, CHX, Irritrol, AgCNPs, and DNase I before NaOCl, CHX, Irritrol, AgCNPs. Dentin blocks were stained with the Live/Dead BacLight Bacterial Viability Kit and viewed with CLSM after irrigation applications. The percentage of dead and viable bacteria was calculated using ImageJ software on CLSM images. At a significance level of p < 0.05, the obtained data were analyzed using one-way Anova and post-hoc Tukey tests. In comparison with NaOCl, CHX had a higher percentage of dead bacteria, both when no pre-enzyme was applied and when DNase I was applied as a pre-enzyme (p < 0.05). There was no difference in the percentage of dead bacteria between the irrigation solutions when trypsin was applied as a pre-enzyme (p > 0.05). AgCNPs showed a higher percentage of dead bacteria when trypsin was applied as a pre-enzyme compared to other irrigation solutions (p < 0.05), while the pre-enzyme application did not affect the percentage of dead bacteria in NaOCl, CHX, and Irritrol (p > 0.05). No irrigation protocol tested was able to eliminate the E. faecalis biofilm. While the application of trypsin as a pre-enzyme improved the antimicrobial effect of AgCNPs, it did not make any difference over other irrigation solutions., (© 2024. The Author(s), under exclusive licence to The Society of The Nippon Dental University.)

Purpose: Bacterial biofilms create a challenge in the treatment of prosthetic joint infection (PJI), and failure to eradicate biofilms is often implicated in the high rates of recurrence. In this study, we aimed to compare the effectiveness of a novel nanoparticle ultrasonication technology on Staphylococcus aureus biofilm eradication compared to commonly used orthopedic irrigation solutions., Methods: Twenty-four sterile, titanium alloy discs were inoculated with a standardized concentration of methicillin-resistant S. aureus and cultured for seven days to allow for biofilm formation. Discs were then treated with either ultrasonicated nanoparticle therapy or irrigation with chlorhexidine gluconate, povidone-iodine or normal saline. The remaining bacteria on each surface was subsequently plated for colony-forming units of S. aureus. Bacterial eradication was reported as a decrease in CFUs relative to the control group. Mann-Whitney U tests were used to compare between groups., Results: Treatment with ultrasonicated nanoparticles resulted in a significant mean decrease in CFUs of 99.3% compared to controls (p < 0.0001). Irrigation with povidone-iodine also resulted in a significant 77.5% reduction in CFUs compared to controls (p < 0.0001). Comparisons between ultrasonicated nanoparticles and povidone-iodine demonstrated a significantly higher reduction in bacterial CFUs in the nanoparticle group (p < 0.0001)., Conclusion: Ultrasonicated nanoparticle were superior to commonly used bactericidal irrigation solutions in the eradication of S. aureus from a titanium surface. Future clinical studies are warranted to evaluate this ultrsonication technology in the treatment of PJI., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Objectives: Antiseptics such as chlorhexidine gluconate (CHG) and octenidine dihydrochloride (OCT) are frequently used in hospitals to prevent and control the transmission of meticillin-resistant Staphylococcus aureus (MRSA). Given the increasing prevalence of reduced CHG susceptibility of MRSA, there are concerns about the possibility of reduced OCT susceptibility. This study evaluated the prevalence of reduced CHG and OCT susceptibility over 3 years, and assessed the association between OCT exposure and reduced OCT susceptibility in MRSA., Methods: MRSA isolates from inpatients who acquired MRSA in an extended-care facility between 2019 and 2021 were included in antiseptic susceptibility testing. Inpatients were exposed to universal daily CHG bathing from January to September 2019, and universal daily OCT bathing after October 2019. The minimum inhibitory concentrations (MICs) of CHG and OCT were determined using the broth microdilution method. Multi-variable logistic regression was used to assess if OCT exposure was independently associated with reduced OCT susceptibility., Results: Of 186 isolates, 179 (96%) had reduced CHG susceptibility (MIC ≥4 mg/L) and 46 (25%) had reduced OCT susceptibility (MIC ≥2 mg/L). Reduced OCT susceptibility rates were 26.9%, 13.8% and 14.3% in 2019, 2020 and 2021, respectively. Reduced CHG susceptibility rates were 95.4%, 100% and 95.9% in 2019, 2020 and 2021, respectively. OCT exposure was not associated with reduced OCT susceptibility (adjusted odds ratio 0.23, 95% confidence interval 0.08-0.75; P=0.014), after adjusting for age, gender, race, year of sample collection, days at risk in facility, hospitalization in preceding year, and MRSA colonization/infection in preceding year., Conclusion: The prevalence of reduced OCT susceptibility has remained low, despite universal OCT bathing for extended inpatient care. However, the rate of reduced CHG susceptibility was high. OCT exposure was not associated with reduced OCT susceptibility in MRSA., (Copyright © 2024 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Validated glass bead sterilization protocols to effectively sterilize rodent surgical instruments after bacterial exposure (for example, cecal contamination) are lacking. To refine current approaches, we added either a multienzyme detergent, neutral pH detergent, or chlorhexidine scrub step before glass bead sterilization of forceps or needle drivers exposed to cecal contents. We exposed sets of forceps and needle drivers to cecal contents, which were then air dried for 3 min. Immediately after, the instruments were wiped several times with a clean, dry paper towel. The contaminated tips were soaked in either a multienzyme or neutral pH detergent ( t = 5 min), chlorhexidine scrub ( t = 2 min), or no pretreatment solution. To further increase debris removal, instruments (from all groups) were brushed using a clean toothbrush. The nonpretreatment instruments were briefly soaked in saline before brushing. After being rinsed with sterile water, all instruments were exposed to a glass bead sterilizer for 60 s at 500 °F (260 °C). Sets were then swabbed for bacterial culturing. Swabs were plated onto either sheep blood agar ( n = 23) or chocolate agar ( n = 20) for aerobic culturing or Brucella agar ( n = 20) for anaerobic culturing. A subset of instruments was sampled to determine organic material presence after treatment using an ATP luminometer ( n = 21). Multiple agar types and bioluminescence were used to more deeply evaluate tool sterility and to differentiate the relative effectiveness of each protocol. From the saline group, only one pair of forceps yielded growth on Brucella agar, and 2 pairs yielded growth on chocolate agar. No other bacterial growth was observed. The use of a pretreatment agent also lowered overall organic contamination levels in needle drivers compared with using only saline. These results indicate that brushing instruments to mechanically remove debris from instruments is paramount to ensure sterility. However, a best practice would be to also use one of the pretreatment options used in this study.

Objective: This study evaluated the antimicrobial effect and cytotoxicity of hypochlorous acid(HClO) obtained from an innovative electrolytic device., Design: The root canals of fifty extracted human teeth were inoculated with Enterococcus faecalis and divided into 5 groups (n = 10): DW (control); 2% chlorhexidine gel(CHX); 2.5% sodium hypochlorite(NaOCl); 250 ppm HClO and 500 ppm HClO. The counting of colony forming units evaluated the decontamination potential of each group. Cytotoxicity was evaluated after inoculation of tested protocols in fibroblastic cells for 3 min, calculating the cell viability. Specific statistical analysis was performed (α = 5%)., Results: The highest bacterial reduction was observed in experimental groups, with no statistical differences from each other (p > 0.05). The highest number of viable cells was observed in control group, followed by 250 ppm HClO and 500 ppm HClO groups, with statistical differences from each other (p < 0.05)., Conclusions: It could be concluded that HClO presented high antimicrobial activity and low cytotoxicity at both tested concentrations., Competing Interests: Declaration of Competing Interest Dr. Liviu Steier owns IP rights on the Dentaqua device. The rest of authors state that they have no financial affiliation (e.g., employment, direct payment, stock holdings, retainers, consultantships, patent licensing arrangements or honoraria) or involvement with any commercial organization with direct financial interest in the subject or materials discussed in this manuscript, nor have any such arrangements existed in the past three years., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Purpose: This study aims to compare the cytotoxic, apoptotic, and oxidative effects of a new cationic disinfectant, Akacid Plus, with chlorhexidine, on the human corneal epithelial cell line., Methods: Time-dependent cytotoxicity studies were performed with the Alamar Blue method. Apoptotic activity was investigated by flow cytometric methods. Reactive oxygen species levels were measured with the ROS cellular test kit. BAX, BCL2 and caspase 3, 9, 12 mRNA expressions were evaluated by PCR, as well as BAX and BCL2 protein expressions by Western-Blot., Results: At the fifth minute of the treatment, the viability was 68.15% with Akacid Plus and 43.95% with chlorhexidine. At the 15th minute, no significant difference was observed with both solutions. In the apoptotic evaluation, Akacid Plus significantly increased the early and late apoptotic activity in the cell line ( p  < 0.0001), while a significant increase was observed in late apoptosis and necrosis levels with chlorhexidine ( p  < 0.001). Chlorhexidine also induced gene expression of BAX, BCL2, caspase 3, 9 and BAX proteins ( p  < 0.05), while reducing protein expression of BCL2 ( p  < 0.001). Akacid Plus induced the gene expressions of BCL2, CASP3 and caspase 9, reduced gene expressions of BAX and caspase 12 and protein expression of BCL2 ( p  < 0.05). No significant difference was observed in the ROS level with both solutions ( p  > 0.05)., Conclusion: Due to the widespread use of cationic polymers in ophthalmology, this new molecule with high antimicrobial activity and relatively low cytotoxicity may be of interest for clinical use. Further investigations are necessary to fully understand the ophthalmologic potential of this solution., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: Analyze the effects of the functionalization of pre-functionalized GIC particles with chlorhexidine on the physicochemical properties and antimicrobial activity., Materials and Methods: Four groups were prepared: (1) GIC (Bioglass R - Biodinamica) - control group; (2) GIC-CHX 1%: Group containing 1% pre-reacted CHX particles; (3) GIC-CHX 2.5%: Group containing 2.5% pre-reacted CHX particles; (4) GIC-CHX 5%: Group containing 5% pre-reacted CHX particles. Hourglass-shaped specimens (10 mm × 2 mm x 1 mm) were fabricated for mechanical tests including cohesive strength (n = 12), modulus of elasticity (n = 12) and microhardness (n = 10). Discs (10 mm × 2 mm) were prepared for the analysis of Ca +2 , PO 4 - and F - ions release (n = 3), and roughness (n = 12). To evaluate the setting time, a Gilmore needle was used according to ISO 9917-1:2016. Disk-shaped specimens (5 × 1mm) were manufactured and subjected to bacterial activity (n = 9) (Streptococcus mutans ATCC 159)., Results: Modulus, roughness, setting time and ions release (Ca +2 , PO 4 - , and F - ) there were no statistically significant differences among the groups (p > 0.05). The setting time did not change with the incorporation of CHX. The GIC-CHX 2.5% and GIC-CHX 5% groups exhibited superior antibacterial activity compared to the control group and GIC-CHX 1% (p < 0.001). The GIC-CHX 5% group showed the highest microhardness values (p < 0.041), cohesive strength (p < 0.009) when compared to the control group., Conclusion: The pre-reacted CHX in GICs was able to confer antimicrobial activity, improve cohesive strength, microhardness, and did not impair ion release, setting time, and roughness., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The prevalence of gingivitis is substantial within the general population, necessitating rigorous oral hygiene maintenance., Objective: This study assessed a Garcinia indica (GI) fruit extract-based mouthrinse, comparing it to a 0.1% turmeric mouthrinse and a 0.2% Chlorhexidine (CHX) mouthrinse. The evaluation encompassed substantivity, staining potential, antimicrobial efficacy and cytocompatibility., Methodology: The study employed 182 tooth sections. For antimicrobial analysis, 64 extracted human teeth coated with a polymicrobial biofilm were divided into four groups, each receiving an experimental mouthrinse or serving as a control group with distilled water. Microbial reduction was assessed through colony forming units (CFU). Substantivity was evaluated on 54 human tooth sections using a UV spectrophotometer, while staining potential was examined on 64 tooth sections. Cytocompatibility was tested using colorimetric assay to determine non-toxic levels of 0.2% GI fruit extract, 0.1% Turmeric, and 0.2% CHX., Results: Data were analysed with one-way ANOVA (α=0.05). Cell viability was highly significant (p<0.001) in the 0.2% GI group (64.1±0.29) compared to 0.1% Turmeric (40.2±0.34) and 0.2% CHX (10.95±1.40). For antimicrobial activity, both 0.2% GI (20.18±4.81) and 0.2% CHX (28.22±5.41) exhibited no significant difference (P>0.05) at end of 12 hours. However, 0.1% Turmeric showed minimal CFU reduction (P<0.001). Substantivity results at 360 minutes indicated statistically significant higher mean release rate in 0.1%Turmeric (12.47±5.84 ) when compared to 0.2% GI (5.02±3.04) and 0.2% CHX (4.13±2.25) (p<0.001). The overall discoloration changes (∆E) were more prominent in the 0.2% CHX group (18.65±8.3) compared to 0.2% GI (7.61±2.4) and 0.1% Turmeric (7.32±4.9) (P<0.001)., Conclusion: This study supports 0.2% GI and 0.1% Turmeric mouth rinses as potential natural alternatives to chemical mouth rinses. These findings highlight viability of these natural supplements in oral healthcare.

Background: The mechanism by which proton pump inhibitors (PPIs) alter gut microbiota remains to be elucidated. We aimed to learn whether PPI induced gut microbiota alterations by promoting oral microbial translocation., Methods: Healthy adult volunteers were randomly assigned: PP group (n=8, 40 mg esomeprazole daily for seven days) and PM group (n=8, 40 mg esomeprazole along with chlorhexidine mouthwash after each meal for seven days). Fecal and saliva samples were analysed using 16S ribosomal RNA sequencing. Mouse models were introduced to confirm the findings in vivo, while the effect of pH on oral bacteria proliferation activity was investigated in vitro., Results: Taxon-based analysis indicated that PPI administration increased Streptococcus abundance in gut microbiota (P<0.001), and the increased species of Streptococcus were found to be from the oral site or oral/nasal sites, in which Streptococcus anginosus was identified as the significantly changed species (P<0.004). Microbial source tracker revealed that PPI significantly increased the contribution of oral bacteria to gut microbiota (P=0.026), and no significant difference was found in PM group (P=0.467). Compared to the baseline, there was a 42-fold increase in gut abundance of Streptococcus anginosus in PP group (P=0.002), and the times decreased to 16-fold in PM group (P=0.029). Mouse models showed that combination of PPI and Streptococcus anginosus significantly increased the gut abundance of Streptococcus anginosus compared with using PPI or Streptococcus anginosus only. Furthermore, Streptococcus anginosus cannot survive in vitro at a pH lower than 5., Conclusions: PPIs altered gut microbiota by promoting oral-originated Streptococcus translocation into gut., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

BACKGROUND Dentin contamination with hemostatic agents before bonding indirect restorations negatively affects the bond strength. However, the consensus on which materials could be used to clean contamination of hemostatic agents has not been explored. The aim of this study was to assess the effect of Katana Cleaner applied on the surface of dentin contaminated with hemostatic agents on the shear bond strength (SBS) of self-adhesive resin cement by comparing it with three other surface cleaners. MATERIAL AND METHODS Ninety dentin specimens were divided into a no contamination group (control) (n=10), 4 groups contaminated with 25% aluminum chloride (Viscostat Clear) (n=40), and 4 groups contaminated with 20% ferric sulfate (Viscostat) (n=40). Subsequently, 4 different cleaners were used for each contamination group (water rinse, phosphoric acid, chlorhexidine, and Katana Cleaner). Then, self-adhesive resin cement was directly bonded to the treated surfaces. All specimens were subjected to 5000 thermal cycles of artificial aging. The shear bond strength was measured using a universal testing machine. RESULTS Two-way analysis of variance showed that the contaminant type as the main factor was statistically non-significant (p=0.655), cleaner type as the main factor was highly significant (p<0.001), and interaction between the contaminant and cleaner was non-significant (p=0.51). The cleaner type was the main factor influencing the bond strength. Phosphoric acid and chlorhexidine showed better performance than Katana Cleaner. CONCLUSIONS Cleaning dentin surface contamination with phosphoric acid and chlorhexidine had better performance than with Katana Cleaner.

Aim: This study investigated the effectiveness of a drug-modified tissue conditioner in an animal model of denture stomatitis., Methods and Results: Wistar rats wore a Candida albicans-contaminated palatal device for 4 days. Next, nystatin (Nys) or chlorhexidine (Chx) were added to a tissue conditioner in their raw or β-cyclodextrin-complexed (βCD) forms at their minimum inhibitory concentrations. As controls, one group was not subjected to any procedure (NC), one group used sterile devices, one group had denture stomatitis but was not treated (DS), and another had the devices relined with the tissue conditioner without the addition of any drug (Soft). After 4 days of treatment, treatment effectiveness was assessed visually, histologically, and through CFU count, and myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) assays. Rats from the Soft, Nys, Nys:βCD, and Chx groups presented a significant decrease in the microbial load compared with the untreated group. Treatment groups showed lower MPO and NAG activity compared to the non-treated group., Conclusions: The addition of antifungals to a soft tissue conditioner can be a promising approach for denture stomatitis treatment., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Objective: The aim of this study was to: (1) evaluate the anti-inflammatory effects of cannabidiol (CBD) on primary cultures of human gingival fibroblasts (HGFs) and (2) to clinically monitor the effect of CBD in subjects with periodontitis., Background: The use of phytocannabinoids is a new approach in the treatment of widely prevalent periodontal disease., Materials and Methods: Cannabinoid receptors were analyzed by western blot and interleukin production detected using enzyme immunoassay. Activation of the Nrf2 pathway was studied via monitoring the mRNA level of heme oxygenase-1. Antimicrobial effects were determined by standard microdilution and 16S rRNA screening. In the clinical part, a placebo-control double-blind randomized study was conducted (56 days) in three groups (n = 90) using dental gel without CBD (group A) and with 1% (w/w) CBD (group B) and corresponding toothpaste (group A - no CBD, group B - with CBD) for home use to maintain oral health. Group C used dental gel containing 1% chlorhexidine digluconate (active comparator) and toothpaste without CBD., Results: Human gingival fibroblasts were confirmed to express the cannabinoid receptor CB2. Lipopolysaccharide-induced cells exhibited increased production of pro-inflammatory IL-6 and IL-8, with deceasing levels upon exposure to CBD. CBD also exhibited antimicrobial activities against Porphyromonas gingivalis, with an MIC of 1.5 μg/mL. Activation of the Nrf2 pathway was also demonstrated. In the clinical part, statistically significant improvement was found for the gingival, gingival bleeding, and modified gingival indices between placebo group A and CBD group B after 56 days., Conclusions: Cannabidiol reduced inflammation and the growth of selected periodontal pathogenic bacteria. The clinical trial demonstrated a statistically significant improvement after CBD application. No adverse effects of CBD were reported by patients or observed upon clinical examination during the study. The results are a promising basis for a more comprehensive investigation of the application of non-psychotropic cannabinoids in dentistry., (© 2024 The Authors. Journal of Periodontal Research published by John Wiley & Sons Ltd.)

Hydrogels from natural sources are attracting increasing interest due to their ability to protect biologically active molecules. Starch extracted from cassava tubers is a promising material for synthesizing these hydrogels. Copolymerization of cassava gum and incorporation of chlorhexidine digluconate (CLX) into the hydrogels is confirmed by changes in the crystallographic profile, as observed through X-ray diffraction, and a shift in the 1000 cm -1 band in the Fourier-transform infrared spectroscopy spectrum. The differential scanning calorimetry reveals changes in the decomposition temperature of the synthesized hydrogels related to CLX volatility. Micrographs illustrate the material's porosity. Release tests indicate a constant linear release over 72 h, while antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans is satisfactory, with 100% effectiveness from 0.5% CLX and the formation of inhibition halos. Toxicity and biocompatibility studies show no cytotoxicity. The continuous release of chlorhexidine is promising for components of biomedical implants and applications as it can ensure antimicrobial action according to specific therapeutic needs., (© 2024 Wiley‐VCH GmbH.)

The revolutionary self-healing function for long-term and safe service processes has inspired researchers to implement them in various fields, including in the application of antimicrobial protective coatings. Despite the great advances that have been made in the field of fabricating self-healing and antimicrobial polymers, their poor transparency and the trade-off between the mechanical and self-healing properties limit the utility of the materials as transparent antimicrobial protective coatings for wearable optical and display devices. Considering the compatibility in the blending process, our group proposed a self-healing, self-cross-linkable poly{( n -butyl acrylate)- co -[ N -(hydroxymethyl)acrylamide]} copolymer (AP)-based protective coating combined with two types of commercial cationic antimicrobial agents (i.e., dimethyl octadecyl (3-trimethoxysilylpropyl) ammonium chloride (DTSACL) and chlorhexidine gluconate (CHG)), leading to the fabrication of a multifunctional modified compound film of (AP/ b %CHG)- grafted - a %DTSACL. The first highlight of this research is that the reactivity of the hydroxyl group in the N -(hydroxymethyl)acrylamide of the copolymer side chains under thermal conditions facilitates the "grafting to" process with the trimethoxysilane groups of DTSACL to form AP- grafted -DTSACL, yielding favorable thermal stability, improvement in hydrophobicity, and enhancement of mechanical strength. Second, we highlight that the addition of CHG can generate covalent and noncovalent interactions in a complex manner between the two biguanide groups of CHG with the AP and DTSACL via a thermal-triggered cross-linking reaction. The noncovalent interactions synergistically serve as diverse dynamic hydrogen bonds, leading to complete healing upon scratches and even showing over 80% self-healing efficiency on full-cut, while covalent bonding can effectively improve elasticity and mechanical strength. The soft nature of CHG also takes part in improving the self-healing of the copolymer. Moreover, it was discovered that the addition of CHG can enhance antimicrobial effectiveness, as demonstrated by the long-term superior antibacterial activity (100%) against Gram-negative ( Escherichia coli ) and Gram-positive ( Staphylococcus aureus ) bacteria and the antifouling function on a glass substrate and/or a silica wafer coated by the modified polymer.

The emergence of resistant fungal species and the toxicity of currently available antifungal drugs are relevant issues that require special consideration. Cyclodextrins inclusion complexes could optimize the antimicrobial activity of such drugs and create a controlled release system with few side effects. This study aimed to assess the in vitro toxicity and antifungal effectiveness of nystatin (Nys) and chlorhexidine (Chx) complexed or not with β-cyclodextrin (βCD). First, a drug toxicity screening was performed through the Artemia salina bioassay. Then, the minimum inhibitory concentrations (MICs) against Candida albicans were determined with the broth microdilution test. After MICs determination, the cytotoxicity of the drugs was evaluated through the methyl-thiazolyl-tetrazolium (MTT) and neutral red (NR) assays and through cell morphology analysis. The PROBIT analysis was used to determine the median lethal concentration (LC 50 ), and the cell viability values were submitted to one-way analysis of variance(ANOVA)/Tukey (α = 0.05). Overall, the βCD-complexed antifungals were less toxic against A. salina than their raw forms, suggesting that inclusion complexes can reduce the toxicity of drugs. The MICs obtained were as follows: Nys 0.5 mg/L; Nys:βCD 4 mg/L; Chx 4 mg/L; and Chx:βCD 8 mg/L. Chx showed significant cytotoxicity (MTT: 12.9 ± 9.6%; NR: 10.6 ± 12.5%) and promoted important morphological changes. Cells exposed to the other drugs showed viability above 70% with no cellular damage. These results suggest that antifungals complexed with βCD might be a biocompatible option for the treatment of Candida-related infections., (© 2024 John Wiley & Sons Ltd.)

Purpose: The goal was to investigate whether the application of antiseptics and fluorides during orthodontic treatment affects the biomechanics of the levelling of dental arches by changing the working properties of nickel-titanium (NiTi) archwires., Methods: The sample consisted of 60 individuals aged 12-22 years (53% females). There were 20 individuals in each experimental group: (I) individuals conducted regular oral hygiene, (II) individuals used a high concentration of fluorides for intensive prophylaxis for the first month; and (III) individuals used chlorhexidine in the same manner. NiTi alloy archwires (dimensions 0.508 × 0.508 mm) were analyzed 3 months after intraoral exposure and compared to as-received NiTi wires. Elastic modulus, yield strength, springback ratio, and modulus of resilience were calculated. Dimensions of the dental arches were analyzed when NiTi alloy (T1) was placed intraorally and after 3 months (T2). Change was quantified as the difference in dimensions (T2-T1). Anterior width-to-length ratio was used as a measure for dental arch shape., Results: Intraoral exposure reduced elastic modulus, yield strength, springback ratio, modulus of resilience, loading, and unloading forces of NiTi wires (p ≤ 0.021). Chlorhexidine mouthwash and gel with high concentration of fluorides did not change these properties more than saliva with regular hygiene. The amount of change of dental arch shape in the maxilla and mandible did not differ significantly between the experimental groups., Conclusion: Using antiseptics or a high concentration of fluorides during orthodontic treatment does not significantly affect the mechanical properties of NiTi wires and would not have clinical implications in changing orthodontic biomechanics., (© 2023. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Objective: To determine the effect of 0.0005% chlorhexidine and tris-EDTA solution on the strength of three commonly used suture types for closure of equine ventral midline celiotomy., Study Design: Controlled laboratory study., Sample Population: Knotted loops (n = 10/group, 150 knot constructs total)., Methods: Strands of 2 polyglactin 910, 3 polyglactin 910, and 2 polydioxanone were tied to form knotted loops. All knotted loops were mounted on a tabletop force measurement machine system and loaded at 100 mm/min until the breaking force (N) was determined. The breaking force (N) of knotted loops using dry suture was recorded at study start, then of knotted loops soaked in either 0.0005% chlorhexidine and tris-EDTA for 20 min followed by incubation in equine serum (treatment) or serum alone (control) for 14 and 21 days. Analysis of variance (ANOVA) compared the breaking force between the treatment and control groups at each time point., Results: There was no significant difference in the breaking force of 2 USP polyglactin 910 (p = .35, confidence interval [CI] = -0.21-0.59), 3 USP polyglactin 910 (p = .61, CI = -0.41-0.24), or 2 USP polydioxanone (p = .76, CI = -0.63-0.46) soaked in 0.0005% chlorhexidine and tris-EDTA solution followed by equine serum when compared to each respective suture soaked in equine serum only., Conclusion/clinical Significance: Since 0.0005% chlorhexidine and tris-EDTA solution did not exhibit a significant effect on the breaking force of the absorbable sutures studied, the solution may be used for incisional lavage in the clinical setting., (© 2023 American College of Veterinary Surgeons.)

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, in vitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an in vitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Objective: To evaluate the topical antiseptic activity of saline, chlorhexidine (CHX), and povidone-iodine (PI) scrubs on the skin of chickens with or without the addition of DuraPrep (DP)., Animals: 7 healthy adult Orpington hens (Gallus gallus domesticus)., Methods: The right apterium corporale laterale was swabbed for standard aerobic bacterial culture and colony-forming unit (CFU) determination. The apterium was divided into 3 areas and treated with sterile saline, CHX, or PI. Samples were collected by swabbing each area before and after additional treatment with DP. CFU's were counted after 48 hours of incubation. Statistical analysis was performed using a linear mixed model with a continuous outcome., Results: Compared to saline, CHX and PI treatment without DP decreased CFU count by 119 (95% CI, 55 to 183; P < .001) and 123 (95% CI, 58 to 187; P < .001), respectively. The application of DP after CHX and PI further decreased CFU counts by 6 (P = .01) and 9 (P = .01), respectively. DP after saline treatment decreased counts by 128 CFU (95% CI, 63 to 192; P < .001). No significant difference was detected between saline, PI, or CHX after DP application (-1.0 CFU; 95% CI, 63.4 to -65.4; P = .98 for both PI and CHX)., Clinical Relevance: CHX or PI provided greater reductions in bacterial CFU than saline, and all combinations with DP provided similar results. No notable cutaneous reactions were detected at any point. This data suggests that a scrub protocol including CHX or PI with DP is acceptable in surgical site preparation of chickens.

Objectives: This ex vivo human study aimed to evaluate the efficacy of NaOCl and chlorhexidine gluconate (CHG) irrigations in eliminating Enterococcus faecalis from the RCS of primary molars., Materials and Methods: Disinfected extracted primary molars were inoculated with E. faecalis for 24 h. Then, the RCS samples were then irrigated with either 2.5% NaOCl, 0.2% and 2% CHG, or sham saline. The samples were collected immediately after irrigation; and 24 h later, the bacterial viability and counts were measured using blood agar and qRT-PCR, respectively. Histological sections were used to measure E. faecalis penetration and viability in dentin tubules using fluorescence microscopy., Results: The recovery of viable E. faecalis after the irrigation of the primary molars showed more significant bactericidal effects of NaOCl and 0.2% and 2% CHG than of saline. Immediately after the irrigation, the NaOCl group showed the greatest reduction in E. faecalis; and 24 h later, all the groups had lower viable E. faecalis than the saline control. The bacterial penetration was also lowest in the NaOCl group, although there was no difference in bacterial viability in the tubules between the groups., Conclusion: In primary teeth, NaOCl and CHG showed similar degrees of bacterial elimination efficacy in terms of E.faecalis., Clinical Relevance: Within the limitations of this study, NaOCl and CHG have the similar ability to perform endodontic irrigation of primary ex vivo teeth regarding the elimination of E.faecalis, but NaOCl penetrates dentin tubules better., (© 2024. The Author(s).)

The endotracheal tube (ETT) affords support for intubated patients, but the increasing incidence of ventilator-associated pneumonia (VAP) is jeopardizing its application. ETT surfaces promote (poly)microbial colonization and biofilm formation, with a heavy burden for VAP. Devising safe, broad-spectrum antimicrobial materials to tackle the ETT bioburden is needful. Herein, we immobilized ciprofloxacin (CIP) and/or chlorhexidine (CHX), through polydopamine (pDA)-based functionalization, onto poly(vinyl chloride) (PVC) surfaces. These surfaces were characterized regarding physicochemical properties and challenged with single and polymicrobial cultures of VAP-relevant bacteria ( Pseudomonas aeruginosa , Acinetobacter baumannii , Klebsiella pneumoniae , Staphylococcus aureus , Staphylococcus epidermidis ) and fungi ( Candida albicans ). The coatings imparted PVC surfaces with a homogeneous morphology, varied wettability, and low roughness. The antimicrobial immobilization via pDA chemistry was still evidenced by infrared spectroscopy. Coated surfaces exhibited sustained CIP/CHX release, retaining prolonged (10 days) activity. CIP/CHX-coated surfaces evidencing no A549 lung cell toxicity displayed better antibiofilm outcomes than CIP or CHX coatings, preventing bacterial attachment by 4.1-7.2 Log 10 CFU/mL and modestly distressing C. albicans . Their antibiofilm effectiveness was endured toward polymicrobial consortia, substantially inhibiting the adhesion of the bacterial populations (up to 8 Log 10 CFU/mL) within the consortia in dual- and even in P. aeruginosa / S. aureus / C. albicans triple-species biofilms while affecting fungal adhesion by 2.7 Log 10 CFU/mL (dual consortia) and 1 Log 10 CFU/mL (triple consortia). The potential of the dual-drug coating strategy in preventing triple-species adhesion and impairing bacterial viability was still strengthened by live/dead microscopy. The pDA-assisted CIP/CHX co-immobilization holds a safe and robust broad-spectrum antimicrobial coating strategy for PVC-ETTs, with the promise laying in reducing VAP incidence.

Background: Decolonization treatment of MRSA carriers is recommended in Denmark, except in households with MRSA-positive children <2 years old (wait-and-see approach)., Objectives: To investigate a wait-and-see approach in children 2-5 years old, and the effect of decolonization treatment of MRSA carriage in all children <6 years old., Patients and Methods: In this retrospective follow-up study, we included MRSA carriers <6 years old in the Capital Region of Denmark from 2007 to 2021. Data were collected from laboratory information systems and electronic patient records. We divided children into age groups of <2 years or 2-5 years and decolonization treatment versus no treatment. Treatment was chlorhexidine body washes and nasal mupirocin, sometimes supplemented with systemic antibiotics. Children were followed until becoming MRSA free, or censoring. The probability of becoming MRSA free was investigated with Cox regression (higher HRs indicate faster decolonization)., Results: Of 348 included children, 226 were <2 years old [56/226 (25%) received treatment] and 122 were 2-5 years old [90/122 (74%) received treatment]. Multivariable analyses did not show a larger effect of decolonization treatment versus no treatment in <2-year-olds (HR 0.92, 95% CI 0.52-1.65) or 2-5-year-olds (HR 0.54, 95% CI 0.26-1.12). Without treatment, 2-5-year-olds tended to clear MRSA faster than <2-year-olds (HR 1.81, 95% CI 0.98-3.37)., Conclusions: We did not find a larger effect of decolonization treatment versus no treatment in children <6 years old, and 2-5-year-olds tended to become MRSA free faster than <2-year-olds. These results support a wait-and-see approach for all children <6 years old, but further studies are needed., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy.)

The increasing prevalence of antimicrobial resistance among bacterial pathogens necessitates novel treatment strategies, particularly in veterinary medicine where otitis in dogs is very common in small animals' clinical routines. Considering this challenge, this study explores the efficacy of aromatic plant compounds (APC), including eugenol (EUG), trans-cinnamaldehyde (TC), and geraniol (GER), and their synergistic potential when combined with the antiseptic agent chlorhexidine (CLX), offering insight into alternative therapeutic approaches. The disk diffusion assay revealed differential sensitivity of Staphylococcus spp. strains to the tested compounds, with EUG and GER showing moderate inhibition zones and TC displaying considerably larger inhibition zones. Further analysis through MIC and MBC determinations suggested that EUG required the highest concentrations to inhibit and kill the bacteria, whereas TC and GER were effective at lower concentrations. Combined with CLX, all three plant-derived compounds demonstrated a significant enhancement of antibacterial activity, indicated by reduced MIC values and a predominantly synergistic interaction across the strains tested. GER was the most potent in combination with CLX, presenting the lowest mean FICi values and the highest fold reductions in MIC. This study emphasizes the APC's potential as an adjunct to conventional antimicrobial agents like CLX. The marked synergy observed, especially with GER, suggests that such combinations could be promising alternatives in managing bacterial otitis in dogs, potentially mitigating the impact of antibiotic resistance., Competing Interests: Declaration of competing interest No potential conflict of interest was reported., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: This study investigated the relationship between bacterial growth, viability, and extracellular polymeric substances (EPS) formation in biofilms, particularly regarding resistance development. It also examined the impact of chemical factors on the EPS matrix and bacterial proliferation in oral biofilms., Methods: Three multi-species oral biofilms were incubated in anaerobic conditions. Three strains of Enterococcus faecalis were incubated in aerobic conditions. The incubation periods ranged from 0 h to 7 days for short-term biofilms, and from 3 to 90 days for long-term biofilms. Fluorescent labeling with carboxyfluorescein diacetate succinimidyl ester (CFSE) and flow cytometry were used to track EPS and bacterial growth. Confocal laser scanning microscopy (CLSM) assessed bacterial viability and EPS structure. Biofilms aged 7, 14, and 21 days were treated with 2 % chlorhexidine (CHX) and 1 % sodium hypochlorite (NaOCl) to evaluate their effects on EPS and bacterial proliferation., Results: Short-term biofilms showed rapid bacterial proliferation and a gradual increase in EPS, maintaining stable viability. In the first two weeks, a significant rise in CFSE indicated growing maturity. From 14 to 90 days, EPS and CFSE levels stabilized. Following treatment, CHX significantly reduced bacterial proliferation, while NaOCl decreased EPS volume., Conclusions: Biofilm development involves a balance between bacterial proliferation and EPS production. The complexity of this process poses challenges in treating biofilm-associated infections, requiring strategies tailored to the biofilm's developmental stage., Clinical Significance: For effective root canal treatment, it is imperative to focus on reducing bacterial proliferation during the early stages of oral infections. In contrast, strategies aimed at minimizing EPS production could be more beneficial for long-term management of these conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study aimed to evaluate the antimicrobial activity of calcium hydroxide-loaded poly(lactic-co-glycolic acid) nanoparticles (CH-loaded PLGA NPs) on multi-species biofilms. Human root blocks were prepared (n = 40), and multi-species suspensions of Candida albicans, Enterococcus faecalis and Streptococcus gordonii were incubated within the root canals for 21 days. Canals (n = 10/group) were then medicated with saline solution (negative control), chlorhexidine (positive control), calcium hydroxide and CH-loaded PLGA NPs for 7 days. Samples taken from the 0.1 mm root canal dentin were collected, and cell growth was detected by culture on BHI agar. The viable cell count of the Ca(OH) 2 , chlorhexidine gel and CH-loaded PLGA NPs group was significantly lower than the normal saline group (p < 0.001). CH-loaded PLGA NPs demonstrated a significant lower viable cell than Ca(OH) 2 (p < 0.001); it has potential as a medicament for endodontic therapy., (© 2023 Australian Society of Endodontology Inc.)

Background: Denture biofilm acts as a potential reservoir for respiratory pathogens, considerably increasing the risk of lung infections, specifically aspiration pneumonia, mainly 48h after hospital admission. The establishment of a straightforward, affordable, and applicable hygiene protocol in a hospital environment for the effective control of denture biofilm can be particularly useful to prevent respiratory infections or reduce the course of established lung disease., Objectives: To evaluate the anti-biofilm effectiveness of denture cleaning protocols in hospitalized patients., Methodology: The maxillary complete dentures (MCDs) of 340 hospitalized participants were randomly cleaned once using one of the following 17 protocols (n=20): brushing with distilled water, toothpaste, or neutral liquid soap (controls); immersion in chemical solutions (1% sodium hypochlorite, alkaline peroxide, 0.12% or 2% chlorhexidine digluconate), or microwave irradiation (650 W for 3 min) combined or not with brushing. Before and after the application of the protocols, the biofilm of the intaglio surface of the MCDs was evaluated using two methods: denture biofilm coverage area (%) and microbiological quantitative cultures on blood agar and Sabouraud Dextrose Agar (CFU/mL). Data were subjected to the Wilcoxon and Kruskal-Wallis tests (α=0.05)., Results: All 17 protocols significantly reduced the percentage area of denture biofilm and microbial and fungal load (P<0.05). The highest percentage reductions in the area of denture biofilm were observed for 1% hypochlorite solution with or without brushing and for 2% chlorhexidine solution and microwave irradiation only in association with brushing (P<0.05). The greatest reductions in microbial and fungal load were found for the groups that used solutions of 2% chlorhexidine and 1% hypochlorite and microwave irradiation, regardless of the association with brushing (P<0.05)., Conclusions: A single immersion for 10 min in 1% sodium hypochlorite, even in the absence of brushing, proved to be a straightforward, rapid, low-cost, and effective protocol for cleaning the dentures of hospitalized patients.

Methionyl-tRNA synthetase (MetRS) catalyzes the attachment of l-methionine (l-Met) to tRNA Met to generate methionyl-tRNA Met , an essential substrate for protein translation within ribosome. Owing to its indispensable biological function and the structural discrepancies with human counterpart, bacterial MetRS is considered an ideal target for developing antibacterials. Herein, chlorhexidine (CHX) was identified as a potent binder of Staphylococcus aureus MetRS (SaMetRS) through an ATP-aided affinity screening. The co-crystal structure showed that CHX simultaneously occupies the enlarged l-Met pocket (EMP) and the auxiliary pocket (AP) of SaMetRS with its two chlorophenyl groups, while its central hexyl linker swings upwards to interact with some conserved hydrophobic residues. ATP adopts alternative conformations in the active site cavity, and forms ionic bonds and water-mediated hydrogen bonds with CHX. Consistent with this synergistic binding mode, ATP concentration-dependently enhanced the binding affinity of CHX to SaMetRS from 10.2 μM (no ATP) to 0.45 μM (1 mM ATP). While it selectively inhibited two representative type 1 MetRSs from S. aureus and Enterococcus faecalis, CHX did not show significant interactions with three tested type 2 MetRSs, including human cytoplasmic MetRS, in the enzyme inhibition and biophysical binding assays, probably due to the conformational differences between two types of MetRSs at their EMP and AP. Our findings on CHX may inspire the design of MetRS-directed antimicrobials in future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)