Introduction: The purpose of this study was to assess the antifungal activity of silver nanoparticles (AgNPs) in combination with calcium hydroxide (Ca(OH)₂) against Candida albicans (C. albicans). Methods: AgNPs was mixed with pure Ca(OH)₂ powder in an aqueous base. A standard suspension (1 × 10⁸ bacterial cells/mL) of C. albicans was prepared in a 96-well plate and incubated on shaker at 37 °C in 100% humidity to allow fungal biofilm formation in infected dentin slices (n = 98). The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of AgNPs alone or with Ca(OH)₂ were determined. The samples were separately placed in 24-well tissue culture plates and divided into three experimental groups (0.03, 0.04, and 0.06) and three control groups; negative (saline) and positive chlorhexidine gel and Ca(OH)₂. Quantitative measurements of fungal activity by XTT colorimetric assay and qualitative measurements using confocal laser microscopy and scanning electron microscopy were performed. Results: The cell viability of C. albicans in the experimental groups was significantly reduced compared to the negative control group. The combination of (AgNPs (0.04%) and Ca(OH)₂) was the most potent against C. albicans. Conclusions: The findings demonstrated that combining silver nanoparticles with Ca(OH)₂ was more effective against C. albicans biofilm compared to Ca(OH)₂ alone, suggesting a combing effect.

Pseudomonas aeruginosa, a nosocomial pathogen, has strong biofilm capabilities, representing the main source of infection in the human body. Repurposing existing drugs has been explored as an alternative strategy to combat emerging antibiotic-resistant pathogens. Fingolimod hydrochloride (FTY720), an immunomodulatory drug for multiple sclerosis, has shown promising antimicrobial effects against some ESKAPE pathogens. Therefore, the effects of FTY720 on the biofilm capabilities of Pseudomonas aeruginosa were investigated in this study. It was determined that FTY720 inhibited the growth of P. aeruginosa PAO1 at 100 µM. The significant reduction in PAO1 cell viability was observed to be dose-dependent. Additional cytotoxicity analysis on human cell lines showed that FTY720 significantly reduced viabilities at sub-inhibitory concentrations of 25–50 µM. Microtiter assays and confocal analysis confirmed reductions in biofilm mass and thickness and the cell survivability ratio in the presence of FTY720. Similarly, virulence production and biofilm-related gene expression (rhlA, rhlB, pilA, pilI, fliC, fliD and algR) were determined. The results demonstrate that pigment production was affected and quantitative real-time PCR analysis showed a variable degree of reduced gene expression in response to FTY720 at 12.5–50 µM. These findings suggest that FTY720 could be repurposed as an alternative antibiofilm agent against Pseudomonas aeruginosa.

Wound healing is a complex physiological process, with scarring and infection caused by Staphylococcus aureus and Pseudomonas aeruginosa being the most common complications. The reutilization of known medications has received increased attention for their role in cell function as small molecules. Examples of these include lovastatin, a cholesterol-lowering agent, and resveratrol, which have multiple biological properties. Both molecules have been reported to improve wound healing and possess antibacterial properties, with conflicting results. The wound-healing capabilities of human mesenchymal stem cells were evaluated after exposure to lovastatin, resveratrol, and their combination through scratch test, migrations assay, and qPCR. Protein docking was performed to assess the lovastatin/resveratrol combination as potential wound-healing targets. AlamarBlue assay was used to determine cell viability. Additionally, the impact of lovastatin and resveratrol combination to inhibit the growth of S. aureus and P. aeruginosa was tested using broth microdilution test and checkerboard assay to determine synergism. The combination of lovastatin 0.1 μM and resveratrol 0.1 μM synergistically improved wound healing and demonstrated an additive effect against S. aureus and P. aeruginosa, presenting potential antibacterial applications.

Dental implants with surface-porous designs have been recently developed. Clinically, peri-implant bone grafting is expected to promote early osseointegration and bone ingrowth when applied with surface-porous dental implants in challenging conditions. The aim of this study was to comparatively analyze peri-implant bone healing around solid implants and surface-porous implants with and without peri-implant bone grafting, using biomechanical and histomorphometrical assessment in a goat iliac bone model. A total of 36 implants (4.1 mm wide, 11.5 mm long) divided into three groups, solid titanium implant (STI; n = 12), porous titanium implants (PTI; n = 12) and PTI with peri-implant bone grafting using biphasic calcium phosphate granules (PTI + BCP; n = 12), were placed bilaterally in the iliac crests of six goats. The goats were sacrificed seven weeks post-operatively and then subjected to biomechanical (n = 6 per group) and histomorphometrical (n = 6 per group) assessment. The biomechanical assessment revealed no significant differences between the three types of implants. Although the peri-implant bone-area (PIBA%) measured by histomorphometry (STI: 8.63 ± 3.93%, PTI: 9.89 ± 3.69%, PTI + BCP: 9.28 ± 2.61%) was similar for the three experimental groups, the percentage of new bone growth area (BGA%) inside the porous implant portion was significantly higher (p < 0.05) in the PTI group (10.67 ± 4.61%) compared to the PTI + BCP group (6.50 ± 6.53%). These data demonstrate that peri-implant bone grafting around surface-porous dental implants does not significantly accelerate early osseointegration and bone ingrowth.

Human gingival fibroblasts (HGnFs) play crucial roles in periodontal wound healing. This in vitro study examined the impact of varying concentrations of topical oxygen fluid (blue^®m) on HGnF morphology, viability, proliferation, oxidative stress and pro-inflammatory cytokine production. The attempt was to underscore the potential of blue^®m as a less cytotoxic alternative to chlorhexidine in the context of tissue-regeneration improvement. Primary HGnF cell cultures were subjected to oxygen fluid (blue^®m) at concentrations of 0.6, 1.2 and 2.4% for a duration of 1 min. The positive control was 0.12% chlorhexidine. Cell morphology as well as actin cytoskeleton were assessed using microscopy and immunofluorescence staining. Cell viability and proliferation were assessed through AlamarBlue and trypan blue assays at 1, 2, 7, 10 and 14 days. Levels of reactive oxygen species (ROS) were quantified using DCFH-DA assay. Pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, MMP-8 and TIMP-1) were assessed through ELISA. HGnF morphology and actin structure were preserved at all oxygen fluid concentrations. Cell viability and proliferation were significantly higher in the 0.6% and 1.2% groups than in the control and chlorhexidine groups (p ≤ 0.05). ROS levels were low at 0.6% and 1.2%, but increased at 2.4% and with chlorhexidine (p ≤ 0.05). Oxygen treatment reduced IL-1β, IL-6, TNF-α and TIMP-1 expression, while MMP-8 levels increased. Chlorhexidine significantly upregulated the expression of all proinflammatory cytokines (p ≤ 0.01). Oxygen fluid (blue^®m) therapy improves the viability and proliferation of gingival fibroblasts and offers anti-inflammatory and preliminary antioxidative effects at the cellular level, especially at lower concentrations (0.6% and 1.2%), indicating potential application in periodontal wound management, subject to clinical validation.

Porphyromonas gingivalis is a key periodontal pathogen whose biofilm and virulence limit the effectiveness of mouthwashes such as chlorhexidine (CHX). This study evaluated the antibacterial, antibiofilm and virulence effects of an oxygen-releasing mouthwash against P. gingivalis, complemented by in silico docking and cytotoxicity testing on human oral fibroblasts. P. gingivalis ATCC 33277 was grown anaerobically. Minimum inhibitory (MIC), bactericidal (MBC) and biofilm inhibitory concentrations (MBIC) were determined by resazurin-based microdilution and crystal violet biofilm assays, with 0.12% CHX as control. Biofilm structure and viability were analysed by confocal microscopy. Quantitative PCR measured expression of 6 virulence- and biofilm-associated genes. Molecular docking of sodium perborate to protein targets used AutoDock GNINA. Fibroblast cytotoxicity (ISO 10993-5 threshold ≥70% viability) was evaluated over 30 min to 24 h. Bluem mouthwash showed concentration-dependent inhibition of P. gingivalis with minimum inhibitory (MIC), bactericidal (MBC) and biofilm inhibitory concentrations (MBIC) values of 0.78%, 1.56% and 3.12%, respectively. At 0.78%, biofilm biomass decreased to around 45% and at concentrations of ≥3.12% was reduced to ≤20%, with greater reduction than 0.12% CHX. Confocal imaging showed reduced biomass and thickness with a predominance of nonviable cells at higher concentrations. Bluem mouthwash was associated with downregulation of virulence-related genes, with fimA and hagA expression reduced at concentrations ≥0.78%, whereas 0.12% CHX increased fimA expression. Molecular docking predicted moderate binding affinities of sodium perborate with key virulence proteins, including kgp and mfa1. Bluem concentrations ≤0.78% maintained noncytotoxic fibroblast viability, while ≥1.56% and 0.12% CHX were cytotoxic across all tested periods. The oxygen-releasing mouthwash inhibited P. gingivalis biofilm formation, modulated virulence-associated gene expression and showed a wider noncytotoxic range on oral periodontal fibroblasts than chlorhexidine. These findings on an oxygen-releasing mouthwash may help guide concentration selection and inform its potential adjunctive use in periodontal protocols, but clinical outcome studies are still needed before routine use can be recommended.