Improved Anti-Biofilm Effect against the Oral Cariogenic Streptococcus mutans by Combined Triclosan/CBD Treatment

The Incorporation of CBD into Biodegradable DL-Lactide/Glycolide Copolymers Creates a Persistent Antibacterial Environment: An In Vitro Study on Streptococcus mutans and Staphylococcus aureus

Background: Cannabidiol (CBD) is a natural compound from the Cannabis sativa L. plant, which has anti-inflammatory, anti-nociceptive, neuroprotective, and antibacterial activities. Objective: The aim of this study was to develop a sustained-release device of CBD that can provide an antibacterial effect against the Gram-positive bacteria Streptococcus mutans and Staphylococcus aureus for extended periods of time. Methods: CBD was incorporated into the biodegradable PURASORB 5010 or PURASORB 7510 DL-lactide/glycolide polymers using either dimethylsulfoxide (DMSO) or acetone as the solvent, and the dried polymer scaffolds were exposed daily to a fresh culture of bacteria. The bacterial growth was determined daily by optical density, and the metabolic activity of biofilms was determined using the MTT assay. Biofilm formation on the polymer scaffolds was visualized by HR-SEM. Its anti-inflammatory effect was determined by measuring the IL-6 release from LPS-stimulated RAW 264.7 macrophages by ELISA. Cell cytotoxicity on normal Vero epithelial cells was determined by the MTT assay. The daily release of CBD was determined by gas chromatography-mass spectrometry (GC-MS). Results: PURASORB 5010/CBD scaffolds had antibacterial activity against S. mutans UA159, S. aureus ATCC25923, and a clinical isolate of a multidrug-resistant S. aureus (MDRSA CI-M) strain for the tested period of up to 17 days. PURASORB 7510/CBD scaffolds also had antibacterial activity, but overall, it was less effective than PURASORB 5010/CBD over time. The addition of PEG400 to the copolymers significantly increased the antibacterial activity of PURASORB 7510/CBD but not of PURASORB 5010/CBD. The daily release of CBD from the polymer scaffolds was sufficient to reduce the LPS-induced IL-6 secretion from RAW 264.7 macrophages, and importantly, it was not cytotoxic to either RAW 264.7 macrophages or Vero epithelial cells. The daily release of CBD was found to be between 1.12 and 9.43 µg/mL, which is far below the cytotoxic dose of 25 µg/mL. Conclusions: The incorporation of CBD into the biodegradable PURASORB 5010 can be used to prepare sustained-release devices for medical purposes where combined antibacterial and anti-inflammatory activities are desirable.

Cannabis Uses in Dentistry: A Bibliometric Analysis

Background: This bibliometric review seeks to understand metrics of papers, authors, journals, and universities, about the benefits of the therapeutic application of Cannabis sativa (CS), as well as the most harmful effects associated to its use. Methods: The main search strategy applied to the topic was conducted in Web Of Science Core Collection on February 2024. A crossmatch of the number of citations was performed in Scopus and Google Scholar. The analyses were carried out in VOSviewer and Altmetric for PubMed and Google Scholar. Results: Of a total of 196 records, 53 articles were included for analysis. There were 25 publications on either therapeutic or harmful effects. In the ranking of subjects, those of greatest interest were general oral health and periodontics, with 53% of the total. The most cited paper was authored by Thomson et al. (2008) with 85 citations, allowing the University of Otago to be the most cited. Although JAMA was the most cited journal, in the dental field this corresponded to the Journal of Clinical Periodontology. In relation to the distribution by country, the United States received the largest number of citations and New Zealand second. Related to dentistry, in the cluster analysis, keywords more occurrent were "periodontal disease" and "periodontitis". Conclusions: In the past 4 years, there has been a superlative growth in CS papers related to oral health effects. This growth follows the social and political events related to CS legalization in some countries and reveals that the use of CS in dentistry is an emerging research field.

Streptococcus mutans biofilms in the establishment of dental caries: a review

Dental caries is considered as the most common and multifactorial disease worldwide, caused by a variety of oral microorganisms like Streptococcus spp., Veillonella spp., Actinomyces spp., Bifidobacterium spp., and Lactobacillus fermentum, which colonize food debris in oral cavities. Of them, Streptococcus mutans is the predominant bacterium and can induce progressive tooth destruction, especially during dentition. The superior characteristics of S. mutans, such as the presence of the cell surface protein P1 and exopolysaccharide-synthesizing enzymes, acid tolerance, biofilm-forming ability mediated by brpA gene, and multidrug resistance, render it a highly virulent pathogen in the etiology of dental caries. Given its significant role in dental caries, extensive research has been conducted over the past few decades, focusing on the development of specific antimicrobial treatments, and other innovative therapeutic approaches. To gain deeper insights into the genetic diversity and epidemiological patterns of S. mutans, various genotypic methods have been developed and successfully employed. By combining the insights gained from genetic studies of S. mutans with the suitable control measures against the biofilm, we can develop innovative and effective strategies for preventing and treating dental caries.

Evaluation of the Effectiveness of a Mouthwash Containing Spilanthol and Cannabidiol on Improving Oral Health in Patients with Gingivitis-Clinical Trial

Background/Objectives: Plaque-associated gingivitis is widely regarded as a local inflammatory condition initiated by the accumulation of a non-specific dental biofilm in the interaction with the host immune system. The initial symptom noticed by the patient is bleeding gums. The use of mouthwash can serve to supplement mechanotherapy. However, there is an increasing interest in mouthwashes comprising natural ingredients, including cannabidiol (CBD) and spilanthol. The objective of this study was to evaluate the effect of an oral rinse containing spilanthol and CBD oil compared to a rinse containing tea tree oil on the oral microbiota and the values of selected oral status indicators in patients with gingivitis. Methods: The study included 40 patients treated with a rinse containing tea tree oil (TTO)/TTO + spilanthol + CBD for a period of 42 days. Patients rinsed their mouth twice daily for 30 s. The patients' oral microbiome was assessed before and after treatment, and bleeding on probing (BOP) and approximal plaque index (API) were assessed. The study was double-blind. Results: API and BOP were reduced in all groups, both the test and control. The most significant decrease in baseline BOP-1 scores was observed in test groups A and D (p = 0.005062 and p = 0.005062, respectively). A significant difference in API improvement was observed between the initial and final visits in the test (A, D) and control (B, C) groups (p = 0.012516, p = 0.005062, p = 0.004028, p = 0.003172, respectively). Conclusions: Firstly, the use of a mouthwash containing cannabidiol (CBD) and spilanthol was demonstrated to be efficacious in the maintenance of oral microbiota homeostasis. Secondly, the combination of TTO with spilanthol and CBD in the rinse was shown to result in a more significant reduction in selected oral health parameters (BOP and API) and anti-inflammatory effects when compared to a rinse with TTO alone. It should be noted that this is a pilot study and will continue.

Ion release, cytocompatibility and microbial inhibition of a novel varnish containing fluoride-doped bioactive glass ceramics: an in vitro study

OBJECTIVES

The study aimed to develop and evaluate in vitro a varnish containing fluoride-doped glass ceramics capable of inhibiting oral microorganisms, releasing hydroxyapatite-forming ions, and ensuring biocompatibility.

MATERIALS AND METHODS

For the production of the experimental varnish (VE), composed of hydrogenated rosin, 10% and 20% by weight of glass ceramics with composition S53P4 (CF0) and doped with F- ions (CF5 and CF10) were incorporated. The EVs were characterized by Rheology, Scanning Electron Microscopy (SEM), FTIR, ion release (fluoride and calcium ions), cytotoxicity on VERO cells, and antimicrobial effect on S. mutans, S. aureus and C. albicans and anti-biofilm effect on S. mutans. The data were analyzed by One-Way ANOVA and Kruskal-Wallis test (P = 0.05).

RESULTS

Homogeneous varnishes with good viscosity were obtained. Varnishes with 20% CF demonstrated biocompatibility and minimum inhibitory concentration (MIC) at concentrations lower than 10 mg/mL and 3.12 mg/mL, respectively, except for C. albicans. An anti-biofilm effect on S. mutans was observed for the varnishes with 20% CF. All varnishes with CF released more F- than the commercial varnish, with V20CF10 standing out, which released 4 times more F- ions in a quarter of the time.

CONCLUSIONS

The V20CF10 varnish is a promising material for dental use in the treatment of early caries lesions, due to its biocompatibility, antimicrobial properties, and release of hydroxyapatite-forming ions.

CLINICAL RELEVANCE

The use of a new varnish that combines antimicrobial properties with hydroxyapatite-forming ion release may prevent or halt the progression of dental caries lesions, offering greater efficacy than currently available varnishes.

Antimicrobial Potential of Cannabinoids: A Scoping Review of the Past 5 Years

In the scenario of fighting bacterial resistance to antibiotics, natural products have been extensively investigated for their potential antibacterial activities. Among these, cannabinoids-bioactive compounds derived from cannabis-have garnered attention for their diverse biological activities, including anxiolytic, anti-inflammatory, analgesic, antioxidant, and neuroprotective properties. Emerging evidence suggests that cannabinoids may also possess significant antimicrobial properties, with potential applications in enhancing the efficacy of conventional antimicrobial agents. Therefore, this review examines evidence from the past five years on the antimicrobial properties of cannabinoids, focusing on underlying mechanisms such as microbial membrane disruption, immune response modulation, and interference with microbial virulence factors. In addition, their synergistic potential, when used alongside standard therapies, underscores their promise as a novel strategy to address drug resistance, although further research and clinical trials are needed to validate their therapeutic use. Overall, cannabinoids offer a promising avenue for the development of innovative treatments to combat drug-resistant infections and reduce the reliance on traditional antimicrobial agents.

Cannabidiol (CBD) Acts as an Antioxidant on Gardnerella vaginalis, Resulting in Reduced Metabolic Activity, Loss of Survivability, and Elimination of Biofilms

Background: Gardnerella vaginalis is a natural inhabitant of the vagina, but when an imbalance occurs in the vaginal microbiota, this bacterium can cause vaginosis, a condition that must be treated when symptomatic and prior to a gynecological intervention. Cannabidiol (CBD) is an anti-inflammatory compound that also has antibacterial activities against several Gram-positive and certain Gram-negative bacteria. Objectives: Since G. vaginalis is an opportunistic pathogenic Gram-variable bacterium, we investigated its response to CBD. Methods: The antibacterial activity of CBD was studied by broth dilution assay, changes in intracellular ATP levels, and the ability of bacteria to recover on chocolate agar plates. The antibiofilm activity was investigated by MTT metabolic assay, crystal violet staining, and HR-SEM. Flow cytometric analyses were performed to measure changes in membrane potential, membrane perforation, and metabolic activity. Reactive oxygen species (ROS) production was analyzed using the nitro blue tetrazolium (NBT) reagent. Gene expression was determined by semi-quantitative real-time PCR, while protein composition was determined by LC-MS/MS analysis. Results: We observed that G. vaginalis clinical isolates exhibited high susceptibility to CBD with a minimum inhibitory concentration (MIC) of 2.5 µg/mL CBD. CBD induced rapid membrane hyperpolarization and caused cytoplasmic leakage of ATP without increasing propidium iodide uptake. This was accompanied by reduced metabolic activity and loss of survivability. Proteomic analysis revealed decreased expression of some ribosomal-associated proteins. CBD exhibited antioxidant activity by reducing intracellular ROS levels in a dose-dependent manner. The antibacterial effect was neutralized by the free radical scavenger α-tocopherol, suggesting the involvement of radicals in executing the antibacterial effect. Importantly, CBD not only prevented the biofilm formation of G. vaginalis but also reduced the metabolic activity and biofilm biomass of preformed, mature biofilms. Real-time PCR analysis of G. vaginalis treated with CBD for 6 h showed an increase in the expression of biofilm-associated genes, suggesting that the antibiofilm activity of CBD is mainly due to its antibacterial effect. CBD did not alter the ability of G. vaginalis to adhere to HeLa cervical carcinoma cells and CBD-treated bacteria were still phagocytosed by RAW264.7 macrophages. Conclusions: Our study shows that CBD exhibits antibacterial and antibiofilm activities against G. vaginalis clinical isolates and is thus a potential drug for the treatment of vaginosis caused by this bacterium.

The antibacterial and antibiofilm role of cannabidiol against periodontopathogenic bacteria

AIMS

Bacterial resistance and systemic risks associated with periodontitis underscore the need for novel antimicrobial agents. Cannabis sativa is a promising source of antimicrobial molecules, and cannabidiol (CBD) attracts significant interest. This study evaluated the antibacterial and antibiofilm activity of CBD against periodontopathogens, and assessed its toxicity in vivo model.

METHODS AND RESULTS

Antibacterial activity was determined by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Biofilm inhibition was determined the minimum inhibitory concentration of biofilm (MICB50). Toxicity was assessed using Caeonorhabditis elegans. The periodontopathogens tested were Actinomyces naeslundii (ATCC 19039), Peptostreptococcus anaerobius (ATCC 27337), Veillonella parvula (ATCC 17745), Fusobacterium nucleatum (ATCC 10953), and Aggregatibacter actinomycetemcomitans (ATCC 43717). CBD exhibited antibacterial effects with MICs of 0.39 to 3.12 µg ml-1 and MICB50 of 0.39 µg ml-1 to 1.56 µg ml-1 against biofilms, without toxicity below 375 µg ml-1.

CONCLUSION

The results suggest that CBD is a non-toxic product with antibacterial and antibiofilm potential, exhibiting promise as a therapeutic alternative for oral diseases.

Antimicrobial Effects of Cannabidiol (CBD)-infused Lozenges against Streptococcus mutans in Oral Health

Cannabidiol presents several benefits, including but not limited to its analgesic, antioxidant, anti-inflammatory, antimicrobial, anti-pruritic, and anti-cancer properties. In this clinical trial, the antimicrobial impact of CBD-infused lozenges on Streptococcus mutans was examined using quantitative polymerized chain reaction (qPCR) bacterial analysis. This clinical trial involved 30 dental hygiene and nursing students who met the inclusion criteria participated in the study and were divided into two groups: experimental and control. The experimental group was given CBD-infused lozenges for 15 days, while the control group received sugar-free candy. Participants consumed one CBD-infused lozenge (300 mg) daily for 15 days, allowing it to dissolve slowly in the mouth for gradual absorption. The study focused on measuring changes in the salivary levels of Streptococcus mutans using quantitative polymerized chain reaction (qPCR) tests. Saliva samples were collected, and DNA extracted for qPCR analysis, assessing the bacterial load. The results, analyzed using a t-test, showed a significant decrease in Streptococcus mutans levels in the experimental group compared to the control group, with a statistically significant difference (p=0.0299).These findings suggest that cannabidiol may effectively reduce Streptococcus mutans in saliva, thus potentially helping to lower the risk of tooth decay as a multifactorial disease. This study underscores the potential of cannabidiol in enhancing oral health and calls for further research to explore its therapeutic applications in dental care.

Anticaries and Antigingivitis Properties of Cannabinoid-Containing Oral Health Products: A Review

To evaluate the anticaries and antigingivitis properties of cannabinoid-containing oral health products. A systematic research strategy was employed. Specific search terms were used, including "Cannabinoids AND dental caries," "Cannabinoids AND oral health," "Cannabinoids AND dental plaque," "Cannabinoids AND gingivitis AND periodontitis," "Cannabinoids AND S. mutans," "Cannabidiol AND oral health," and "Cannabidiol AND oral biofilm." The search was conducted in PubMed, Cochrane, and EBSCO Host databases. The search yielded a total of 73 articles, out of which 15 articles (20.5%) were relevant to the scope of this systematic review. Among the relevant articles, only eight (10.9%) directly addressed the research question. The findings from these articles suggest that cannabinoids have the potential to reduce the metabolism of cariogenic bacteria, specifically Streptococcus mutans, and decrease the number of bacterial colonies in dental plaque. In vitro studies also demonstrated a significant inhibitory effect of cannabinoids on oral biofilms and create a considerable inhibitory zone of growth when investigated on oral biofilms in vitro. Furthermore, CBD exhibited antibacterial properties against Porphyromonas gingivalis, a primary pathogen associated with periodontal disease. The current review shows insufficient data to conclude on the anticaries and antigingivitis effects of cannabinoids. Despite extensive research on their systemic therapeutic benefits, their oral health impact remains underexplored, lacking clinical trials and primary research.

Berberine and chlorogenic acid-assembled nanoparticles for highly efficient inhibition of multidrug-resistant Staphylococcus aureus

Due to the bacteria resistant to various first-line antibiotics, it is urgent to develop efficient antibiotic alternatives and formulate multidimensional strategies. Herein, supramolecular Chinese medicine nanoparticles are synthesized by self-assembly of berberine (BBR) and chlorogenic acid (CGA), which exhibit higher inhibitory effect against Staphylococcus aureus and multidrug-resistant Staphylococcus aureus (MRSA) than ampicillin, oxacillin, BBR, CGA, as well as mixture of BBR and CGA (minimum inhibitory concentration, MIC = 1.5 µM). The inhibition by BBR/CGA nanoparticles (2.5 µM) reaches 99.06 % for MRSA, which is significantly higher than ampicillin (29.03 %). The nanoparticles with 1/2 MIC can also synergistically restore the antimicrobial activity of ampicillin against MRSA. Moreover, in vivo therapeutic outcome in the murine skin wound infection model suggests that the nanoparticles are able to promote wound healing. This study provides new insights in the application of Chinese medicines self-assembly for MRSA inhibition, as well as solutions for potential persistent clinical infections and drug deficiencies.

Enhanced Anti-Bacterial Activity of Arachidonic Acid against the Cariogenic Bacterium Streptococcus mutans in Combination with Triclosan and Fluoride

Dental caries is a global health problem that requires better prevention measures. One of the goals is to reduce the prevalence of the cariogenic Gram-positive bacterium Streptococcus mutans. We have recently shown that naturally occurring arachidonic acid (AA) has both anti-bacterial and anti-biofilm activities against this bacterium. An important question is how these activities are affected by other anti-bacterial compounds commonly used in mouthwashes. Here, we studied the combined treatment of AA with chlorhexidine (CHX), cetylpyridinium chloride (CPC), triclosan, and fluoride. Checkerboard microtiter assays were performed to determine the effects on bacterial growth and viability. Biofilms were quantified using the MTT metabolic assay, crystal violet (CV) staining, and live/dead staining with SYTO 9/propidium iodide (PI) visualized by spinning disk confocal microscopy (SDCM). The bacterial morphology and the topography of the biofilms were visualized by high-resolution scanning electron microscopy (HR-SEM). The effect of selected drug combinations on cell viability and membrane potential was investigated by flow cytometry using SYTO 9/PI staining and the potentiometric dye DiOC2(3), respectively. We found that CHX and CPC had an antagonistic effect on AA at certain concentrations, while an additive effect was observed with triclosan and fluoride. This prompted us to investigate the triple treatment of AA, triclosan, and fluoride, which was more effective than either compound alone or the double treatment. We observed an increase in the percentage of PI-positive bacteria, indicating increased bacterial cell death. Only AA caused significant membrane hyperpolarization, which was not significantly enhanced by either triclosan or fluoride. In conclusion, our data suggest that AA can be used together with triclosan and fluoride to improve the efficacy of oral health care.

Anti-bacterial and anti-biofilm activities of arachidonic acid against the cariogenic bacterium Streptococcus mutans

Streptococcus mutans is a Gram-positive, facultative anaerobic bacterium, which causes dental caries after forming biofilms on the tooth surface while producing organic acids that demineralize enamel and dentin. We observed that the polyunsaturated arachidonic acid (AA) (ω-6; 20:4) had an anti-bacterial activity against S. mutans, which prompted us to investigate its mechanism of action. The minimum inhibitory concentration (MIC) of AA on S. mutans was 25 μg/ml in the presence of 5% CO2, while it was reduced to 6.25-12.5 μg/ml in the absence of CO2 supplementation. The anti-bacterial action was due to a combination of bactericidal and bacteriostatic effects. The minimum biofilm inhibitory concentration (MBIC) was the same as the MIC, suggesting that part of the anti-biofilm effect was due to the anti-bacterial activity. Gene expression studies showed decreased expression of biofilm-related genes, suggesting that AA also has a specific anti-biofilm effect. Flow cytometric analyses using potentiometric DiOC2(3) dye, fluorescent efflux pump substrates, and live/dead SYTO 9/propidium iodide staining showed that AA leads to immediate membrane hyperpolarization, altered membrane transport and efflux pump activities, and increased membrane permeability with subsequent membrane perforation. High-resolution scanning electron microscopy (HR-SEM) showed remnants of burst bacteria. Furthermore, flow cytometric analysis using the redox probe 2',7'-dichlorofluorescein diacetate (DCFHDA) showed that AA acts as an antioxidant in a dose-dependent manner. α-Tocopherol, an antioxidant that terminates the radical chain, counteracted the anti-bacterial activity of AA, suggesting that oxidation of AA in bacteria leads to the production of cytotoxic radicals that contribute to bacterial growth arrest and death. Importantly, AA was not toxic to normal Vero epithelial cells even at 100 μg/ml, and it did not cause hemolysis of erythrocytes. In conclusion, our study shows that AA is a potentially safe drug that can be used to reduce the bacterial burden of cariogenic S. mutans.

Polyglactin 910 Meshes Coated with Sustained-Release Cannabigerol Varnish Inhibit Staphylococcus aureus Biofilm Formation and Macrophage Cytokine Secretion: An In Vitro Study

Synthetic surgical meshes are commonly used in abdominal wall reconstruction surgeries to strengthen a weak abdominal wall. Common mesh-related complications include local infection and inflammatory processes. Because cannabigerol (CBG) has both antibacterial and anti-inflammatory properties, we proposed that coating VICRYL (polyglactin 910) mesh with a sustained-release varnish (SRV) containing CBG would prevent these complications. We used an in vitro infection model with Staphylococcus aureus and an in vitro inflammation model of lipopolysaccharide (LPS)-stimulated macrophages. Meshes coated with either SRV-placebo or SRV-CBG were exposed daily to S. aureus in tryptic soy medium (TSB) or macrophage Dulbecco's modified eagle medium (DMEM). Bacterial growth and biofilm formation in the environment and on the meshes were assessed by changes in optical density, bacterial ATP content, metabolic activity, crystal violet staining, spinning disk confocal microscopy (SDCM), and high-resolution scanning electron microscopy (HR-SEM). The anti-inflammatory effect of the culture medium that was exposed daily to the coated meshes was analyzed by measuring the release of the cytokines IL-6 and IL-10 from LPS-stimulated RAW 264.7 macrophages with appropriate ELISA kits. Additionally, a cytotoxicity assay was performed on Vero epithelial cell lines. We observed that compared with SRV-placebo, the segments coated with SRV-CBG inhibited the bacterial growth of S. aureus in the mesh environment for 9 days by 86 ± 4% and prevented biofilm formation and metabolic activity in the surroundings for 9 days, with respective 70 ± 2% and 95 ± 0.2% reductions. The culture medium that was incubated with the SRV-CBG-coated mesh inhibited LPS-induced secretion of IL-6 and IL-10 from the RAW 264.7 macrophages for up to 6 days without affecting macrophage viability. A partial anti-inflammatory effect was also observed with SRV-placebo. The conditioned culture medium was not toxic to Vero epithelial cells, which had an IC₅₀ of 25 µg/mL for CBG. In conclusion, our data indicate a potential role of coating VICRYL mesh with SRV-CBG in preventing infection and inflammation in the initial period after surgery.