Current uses of chlorhexidine for management of oral disease: a narrative review

Dental applications of Punica granatum L. in the treatment of gingivitis: A review of ethnomedicinal uses, randomized clinical trials, and antibacterial potential against Porphyromonas gingivalis

ETHNOPHARMACOLOGICAL RELEVANCE

Mouthwashes based on medicinal plants have demonstrated benefits in controlling plaque and inflammation, acting positively on the oral hygiene of patients with gingivitis. In traditional medicine, Punica granatum L. has been used to treat oral diseases in countries in Europe, Asia, North America, and Africa.

AIM OF THE STUDY

The present study aimed to conduct a comprehensive review on the dental applications of Punica granatum L. for the treatment of gingivitis, including ethnomedicinal uses, analysis of randomized clinical trials, antibacterial activity against Porphyromonas gingivalis, mechanisms of action of phytochemicals isolated from this plant, and preclinical toxicity.

MATERIALS AND METHODS

The literature was retrieved from Google Scholar, PubMed®, SciELO, and ScienceDirect®, since the first report published on the topic in 2001 until March 2024.

RESULTS

Several clinical trials have demonstrated that mouthwashes containing P. granatum have equal or better efficacy than chlorhexidine in treating patients with gingivitis, confirming the indications for use of this plant by traditional communities. However, reports on the in vitro antibacterial activity of extracts from the fruits of this plant have not shown clinical relevance against the pathogen P. gingivalis. The ellagitannin punicalagin isolated from P. granatum has shown potential against several strains of Gram-positive and Gram-negative bacteria, but, to date, this compound has not yet been tested against P. gingivalis. It is likely that the mechanisms of action of flavonoids, such as quercetin, are involved in the inhibition of the activities of the RgpA, RgpB, and Kgp proteases of P. gingivalis.

CONCLUSIONS

In summary, natural products obtained from P. granatum do not present toxic side effects and can be considered as possible substitutes of commercial products recommended for the treatment of gingivitis and other oral diseases.

Antibacterial Activity and Randomised Controlled Trial of Chlorhexidine-Coated Floss on Gingival Bleeding

INTRODUCTION

While Chlorhexidine mouthwash is widely studied for the treatment of periodontal disease, research on chlorhexidine in the form of dental floss is limited. This study aims to evaluate the effect of chlorhexidine wax-coated dental floss on dental plaque accumulation and gingival bleeding. Additionally, antibacterial activity and cellular toxicity were also investigated in vitro.

METHODS

Various concentrations of chlorhexidine wax-coated floss (0%, 0.12%, 1%, and 2%) were prepared. The antibacterial activity against Streptococcus mutans was studied using a disc diffusion assay. Cellular toxicity was assessed in L929 cells and human gingival fibroblasts using an MTT assay. To evaluate the effects on plaque accumulation and gingival bleeding, 27 participants were randomly divided into 3 groups: 1) 0% chlorhexidine wax-coated dental floss (control), 2) 0.12% chlorhexidine wax-coated dental floss, and 3) 1% chlorhexidine wax-coated dental floss. All participants were instructed to use the provided dental floss once daily at bedtime for 14 days. Six sites per tooth were evaluated for the Quigley-Hein plaque index and bleeding index (BI) at day 0 (baseline) and day 15. All fully erupted teeth, except the third molars, were examined.

RESULTS

Chlorhexidine-coated floss exhibited antibacterial activity against S. mutans in a dose-dependent manner. In an in-vitro study, a 2% concentration of chlorhexidine in the floss was found to be highly toxic, leading to its exclusion from clinical trials. After 14 days of use, significantly lower levels of BI were observed in the groups using chlorhexidine wax-coated dental floss, compared to the control. Additionally, there was no significant difference in BI between the 0.12% and 1% chlorhexidine wax-coated dental floss groups. However, no significant difference in plaque index was found between the groups using chlorhexidine wax-coated dental floss and the control group.

CONCLUSIONS

This study demonstrated the antibacterial and anti-gingivitis properties of chlorhexidine wax-coated dental floss. Our results showed that using chlorhexidine wax-coated dental floss at a concentration as low as 0.12% could significantly reduce gingival bleeding. However, no additional benefit of chlorhexidine wax-coated dental floss on dental plaque accumulation was found.

Povidone Iodine vs Chlorhexidine Gluconate for Preoperative Skin Antisepsis: A Systematic Review and Meta-analysis of Randomised Controlled Trials

BACKGROUND

Surgical site infection (SSI) remains a challenge in healthcare, contributing to prolonged hospital stays, increased healthcare costs, and adverse patient outcomes, including mortality. Effective preoperative skin disinfection interventions, such as povidone-iodine (PVI) and chlorhexidine (CHG), are widely used but their efficacy remains debated. To address this gap, this meta-analysis aims to evaluate the efficacy of PVI and CHG.

METHOD

We searched PubMed, Embase, and Cochrane databases up to June 2024 to identify studies comparing PVI versus CHG for preoperative skin antisepsis. We calculated odds ratios (ORs) for binary outcomes, with 95% confidence intervals (CIs). A random-effects model was used with statistical significance set at p < 0.05. Data were analysed using R software (version 4.4.0), and heterogeneity was assessed using I2 statistics.

FINDINGS

Sixteen randomised controlled trials (RCTs) were included, involving a total of 13,721 patients, among whom 6,836 (49.8%) received PVI. Compared to CHG, PVI was associated with a non-significant reduction in deep SSI (OR 1.00; 95% CI 0.66 - 1.50; p = 0.994), but an increased risk of overall SSI (OR 1.25; 95% CI 1.06 - 1.48; p = 0.007) and superficial SSI (OR 1.67; 95% CI 1.25 - 2.24; p < 0.001).

CONCLUSION

PVI as preoperative skin antisepsis demonstrated a non-significant reduction in deep SSI compared to CHG but was associated with an increased risk of overall and superficial SSI. Despite these findings, PVI remains an effective option, especially in resource-limited settings. Further research is needed to optimise its use and improve infection prevention strategies in clinical practice.

A Rare Case of Allergic Stomatitis Due to the Consumption of Boiled Cassava

Introduction

Allergic stomatitis is an oral inflammatory disorder characterized by a painful, burning sensation, or itchiness in the oral cavity which clinically appears as erythematous plaques, vesiculation, ulceration, and/or hyperkeratosis. The causative agents include drugs, dental materials, and food ingredients. Allergic stomatitis might develop after a person eats, touches, or inhales food allergen which then triggers the hypersensitivity reaction. The most common types of food hypersensitivity generally involve type 1 and type 4 reactions or a combination of both.

Purpose

This case report aims to discuss a case of allergic stomatitis caused by one of the staple food ingredients in Indonesia: cassava.

Case

A 26-year-old woman came with complaints of burning pain from multiple ulcers on her right inner cheek. The ulcers appeared shortly after the patient ate boiled cassava, extending to the soft palate and causing pain when swallowing food. The patient has a history of asthma.

Case Management

The patient was referred for a total IgE examination with a result of 271.41 KIU/L (normal < 150 KIU/L). She was prescribed an antiseptic mouthwash and topical corticosteroids for palliative therapy. Additionally, multivitamins were also prescribed to speed up the healing process.

Conclusion

Allergic stomatitis can be caused by food ingredients, even those considered healthy or non-allergenic. A complete anamnesis, including the patient's food history, along with supporting examinations, must be carried out to confirm the diagnosis and select appropriate therapy.

Advances in the use of chlorhexidine for periodontitis treatment in diabetic patients: A review

Periodontitis and diabetes mellitus exhibit a bidirectional relationship. This narrative review descriptively outlines the role of chlorhexidine in the periodontal treatment of diabetic patients, focusing on its antimicrobial mechanisms against microbial communities and its antiplaque effects. Although chlorhexidine is proven to be effective in combating microbial presence and improving gingivitis with substantial supporting evidence, its impact on glycemic control and insulin resistance in diabetic patients remains contentious. Additionally, the effectiveness of chlorhexidine as an adjunctive chemotherapeutic in the periodontal treatment of gestational diabetes has not yet been studied, highlighting a gap in research that necessitates further prospective studies and randomized controlled trials. Considering the interconnection between periodontal inflammation and glycemic levels, this article finally advocates for collaborative care between dental and medical professionals to manage periodontitis in diabetic patients effectively.

Investigation of Chlorhexidine and Chitosan Gel-Based Coatings for the Prevention of Intravascular Catheter-Associated Infections Following Quality by Design Approach

Intravascular catheter-associated infections pose a significant threat to the health of patients because of biofilm formation. Hence, it is imperative to exploit cost-effective approaches to improve patient compliance. With this aim, our present study reported the potential of an antimicrobial polymeric gel coating of chitosan (CS) and chlorhexidine (CHX) on the marketed urinary catheters to minimize the risk of biofilm formation. The study involved the implementation of the Quality by Design (QbD) approach by identifying the critical parameters that can affect the coating of the catheter's surface in any possible way. Later, design of experiments (DoE) analysis affirmed the lack of linearity in the model for the studied responses in a holistic manner. Moreover, in vitro studies were conducted for the evaluation of various parameters followed by the antibiofilm study. The coating exhibited promising release of CHX in the artificial urinary media together with retention of the coating on the catheter's surface. Therefore, this study aims to emphasize the importance of a systematic and quality-focused approach by contributing to the development of a safe, effective, and reliable catheter coating to enhance intravascular catheter safety.

Oral microbiota and metabolites: key players in oral health and disorder, and microbiota-based therapies

The review aimed to investigate the diversity of oral microbiota and its influencing factors, as well as the association of oral microbiota with oral health and the possible effects of dysbiosis and oral disorder. The oral cavity harbors a substantial microbial burden, which is particularly notable compared to other organs within the human body. In usual situations, the microbiota exists in a state of equilibrium; however, when this balance is disturbed, a multitude of complications arise. Dental caries, a prevalent issue in the oral cavity, is primarily caused by the colonization and activity of bacteria, particularly streptococci. Furthermore, this environment also houses other pathogenic bacteria that are associated with the onset of gingival, periapical, and periodontal diseases, as well as oral cancer. Various strategies have been employed to prevent, control, and treat these disorders. Recently, techniques utilizing microbiota, like probiotics, microbiota transplantation, and the replacement of oral pathogens, have caught the eye. This extensive examination seeks to offer a general view of the oral microbiota and their metabolites concerning oral health and disease, and also the resilience of the microbiota, and the techniques used for the prevention, control, and treatment of disorders in this specific area.

New Insights Regarding the Use of Relevant Synthetic Compounds in Dentistry

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.

Impact of different chemical denture cleansers on the properties of digitally fabricated denture base resin materials

PURPOSE

To compare the impact of three different chemical denture cleansers (CDCs) (Corega, chlorhexidine, and hydrogen peroxide) on the surface roughness, microhardness, and color stability of 3D-printed, computer-aided design and computer-aided manufacturing (CAD-CAM) milled, and heat-polymerized denture base material (DBM).

MATERIALS AND METHODS

A total of 420 disc-shaped specimens (10 ± 0.1 × 2 ±0.1 mm) were fabricated using three different construction techniques: three-dimensional (3D) printing (n = 140), CAD-CAM milling (n = 140), and heat-polymerization (n = 140). Sixty specimens (20 of each DBM) were used for baseline (pre-immersion) measurements (T1) for the tested surface properties (hardness [n = 10/material] and roughness [n = 10/material]). The remaining 360 specimens (n = 120/material) were investigated for surface roughness, microhardness, and color change after immersion for 1 year (T2) in distilled water or CDCs (n = 30/solution and n = 10/test). The data were analyzed using two-way ANOVA, one-way ANOVA followed by post-hoc Tukey's test at a significance level of less than 0.05.

RESULTS

Significant differences were observed in the effects of the tested CDCs on the surface roughness, micro-hardness, and color stability of varying DBM specimens (p < 0.05). Corega showed the highest surface roughness and color change in all DBMs while H2O2 resulted in the lowest microhardness for all DBMs. The lowest changes in all tested properties were seen with distilled water followed by chlorhexidine. A significant effect of type of cleanser, denture base material, and the interaction between the two was seen on all measured properties (p < 0.05).

CONCLUSIONS

The tested CDCs significantly affected the surface properties of all DBMs but at varying degrees. Corega produced the highest negative effect on roughness and color change while H2O2 dramatically affected the microhardness. Prolonged use of CDCs should be cautiously followed.

Antimicrobial Activity of Antibacterial Sutures in Oral Surgery: A Scoping Review

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.

Oral Hygiene With Neutral Electrolyzed Water and Systemic Therapy Increases Gastric Helicobacter pylori Eradication and Reduces Recurrence

OBJECTIVES

Helicobacter pylori gastric infection strongly correlates with gastric diseases such as chronic gastritis, functional dyspepsia, and complications such as peptic ulcers and gastric cancer. In developing countries, systemic therapies are not usually successful due to elevated antibiotic resistance. Additionally, oral H. pylori infection and periodontal disease correlate with gastric treatment failures. This study aimed to explore the effect of an integral therapy, comprising oral hygiene and concomitant systemic treatment, to increase the eradication of gastric infection and recurrences.

MATERIALS AND METHODS

A prospective, randomized, four-arm, parallel-group, open-label clinical trial was conducted to investigate the efficacy of integral therapy to eradicate gastric H. pylori infection and avoid recurrences in double-positive (real-time PCR oral and gastric infection) patients. Oral hygiene involved mouthwash with neutral electrolyzed water (NEW), with or without periodontal treatment. One hundred patients were equally distributed into four groups: NS, NS-PT, NEW, and NEW-PT. All patients had concomitant systemic therapy and additionally, the following oral treatments: mouthwash with normal saline (NS), periodontal treatment and mouthwash with normal saline (NS-PT), mouthwash with NEW (NEW), and periodontal treatment and mouthwash with NEW (NEW-PT). Gastric and oral infection and symptoms were evaluated one and four months after treatments.

RESULTS

Integral therapy with NEW-PT increased gastric eradication rates compared with NS or NS-PT (84%-96% vs. 20%-56%; p < 0.001). Even more, a protective effect of 81.2% (RR = 0.1877; 95% CI: 0.0658-0.5355; p = 0.0018) against recurrences and 76.6% (RR = 0.2439; 95% CI: 0.1380-0.4310; p < 0.001) against treatment failure (eradication of infection and associated symptoms) was observed in patients from the NEW and NEW-PT groups.

CONCLUSIONS

Implementation of oral hygiene and systemic treatment can increase the eradication of gastric infection, associated symptoms, and recurrences. NEW is recommended as an antiseptic mouthwash due to its efficacy and short- and long-term safety.

Antimicrobial effects of surface pre-reacted glass-ionomer (S-PRG) eluate against oral microcosm biofilm

This study investigated the antimicrobial activity of surface pre-reacted glass ionomer eluate (S-PRG) against oral microcosm biofilms collected from the oral cavity of patients. Dental biofilm samples were collected from three volunteers to form microcosm biofilms in vitro. Initially, screening tests were carried out to determine the biofilm treatment conditions with S-PRG eluate. The effects of a daily treatment for 5 min using three microcosm biofilms from different patients was then evaluated. For this, biofilms were formed on tooth enamel specimens for 120 h. Biofilms treated with 100% S-PRG for 5 min per day for 5 days showed a reduction in the number of total microorganisms, streptococci and mutans streptococci. SEM images confirmed a reduction in the biofilm after treatment. Furthermore, S-PRG also reduced lactic acid production. It was concluded that S-PRG eluate reduced the microbial load and lactic acid production in oral microcosm biofilms, reinforcing its promising use as a mouthwash agent.

Enterococcus Phage vB_EfaS_HEf13 as an Anti-Biofilm Agent Against Enterococcus faecalis

Enterococcus faecalis is a Gram-positive bacterium that is frequently found in the periapical lesion of patients with apical periodontitis. Its biofilm formation in root canal is closely related to the development of refractory apical periodontitis by providing increased resistance to endodontic treatments. Phage therapy has recently been considered as an efficient therapeutic strategy in controlling various periodontal pathogens. We previously demonstrated the bactericidal capacities of Enterococcus phage vB_EfaS_HEf13 (phage HEf13) against clinically-isolated E. faecalis strains. Here, we investigated whether phage HEf13 affects biofilm formation and pre-formed biofilm of clinically-isolated E. faecalis, and its combinatory effect with endodontic treatments, including chlorhexidine (CHX) and penicillin. The phage HEf13 inhibited biofilm formation and disrupted pre-formed biofilms of E. faecalis in a dose- and time-dependent manner. Interestingly, phage HEf13 destroyed E. faecalis biofilm exopolysaccharide (EPS), which is known to be a major component of bacterial biofilm. Furthermore, combined treatment of phage HEf13 with CHX or penicillin more potently inhibited biofilm formation and disrupted pre-formed biofilm than either treatment alone. Confocal laser scanning microscopic examination demonstrated that these additive effects of the combination treatments on disruption of pre-formed biofilm are mediated by relatively enhanced reduction in thickness distribution and biomass of biofilm. Collectively, our results suggest that the effect of phage HEf13 on E. faecalis biofilm is mediated by its EPS-degrading property, and its combination with endodontic treatments more potently suppresses E. faecalis biofilm, implying that phage HEf13 has potential to be used as a combination therapy against E. faecalis infections.

Insights into the Cytotoxicity and Irritant Potential of Chlorhexidine Digluconate: An In Vitro and In Ovo Safety Screening

Chlorhexidine (CHX) represents one of the most commonly used antiseptics in dentistry and other medical-pharmaceutical fields due to its broad-spectrum antimicrobial activity. However, the potential toxic events arising from its common use in practice has become a subject of increasing concern. Thus, the present study was designed to investigate the potential toxicity of CHX digluconate at concentrations covering its antibacterial properties (0.0002-0.2%) in HGF primary gingival fibroblasts, HaCaT immortalized human keratinocytes, and JB6 Cl 41-5a epidermal cells, as well as its irritant action in ovo. Our results indicate that CHX exerted a concentration- and time-dependent cytotoxicity in all cell lines, which was evidenced by the reduction in cell viability, number, and confluence, damaged cell membrane integrity, impaired cell morphology, and specific apoptotic nuclear shape. The highest cytotoxicity was caused by CHX digluconate 0.02% and 0.2%, concentrations, at which an irritant effect on the chorioallantoic membrane was also observed. The novel findings revealed in this research contribute to the overall safety profile of CHX and stand as a basis for further investigations in this regard.

The positive effects of preoperative chlorhexidine rinse to reduce postoperative pneumonia after kidney transplantation surgery

BACKGROUND

Postoperative pneumonia is one of the most observed hospital-acquired infections and increases the postoperative mortality rate. Further, it drives the healthcare systems under a severe financial burden. Preventing postoperative pneumonia is an incredibly challenging issue for clinicians. Since immunosuppression therapy, the patients who had kidney transplants are more vulnerable to postoperative infections. There is no data in the scientific literature focusing on the effects of preoperative oral care with chlorhexidine antiseptic solutions on postoperative pneumonia in kidney transplantation surgery cases. In the present research, we studied this topic.

METHODS

A prospective, randomized clinical trial was conducted at our institution between August 2020 and August 2022. Group A: Received 0.12 % chlorhexidine oral rinse preoperatively; Group B: Not received 0.12 % chlorhexidine oral rinse preoperatively. We analyzed the differences between the two trial groups using a chi-square or t-test. The Mann-Whitney U test was used for the categorical data.

RESULTS

Nine patients (17.6 %) were diagnosed with postoperative pneumonia in Group A and fourteen (25.9 %) in Group B (p < 0.05). Hospitalization time of Group B was prolonged (p < 0.05). In multivariate analysis, significant risk factors associated with postoperative pneumonia were advanced age, diabetes mellitus, smoking, delayed graft function and not gargling with 0.12 % chlorhexidine (p < 0.05).

CONCLUSIONS

To reduce postoperative pneumonia risk in patients undergoing kidney transplantation surgery, an oral health protocol including 0.12 % chlorhexidine mouth rinse seems beneficial.

4-hydroxy-3-methoxybenzaldehyde causes attrition of biofilm formation and quorum sensing-associated virulence factors of Streptococcus mutans

OBJECTIVE

The present study investigated the effects of 4-hydroxy-3-methoxybenzaldehyde (4-H-3-MB) against Streptococcus mutans (S. mutans) using an in vitro cariogenic biofilm model.

DESIGN

The antimicrobial susceptibility of biofilm-forming S. mutans was evaluated by disc diffusion method. In vitro investigations were performed using crystal violet staining assay (biofilm assay), exopolysaccharide (EPS) assay, acid production, growth curve analysis, optical microscopic, and FE-SEM analyses to determine the antibiofilm activity of 4-H-3-MB.

RESULTS

S. mutans (SDC-05) was resistant to ampicillin, piperacillin/tazobactam and ceftriaxone, whereas the other strains of S. mutans (SDC-01, 02, 03 and SDC-04) were sensitive to all the antibiotics tested. 4-H-3-MB showed promising antibiofilm activity on S. mutans UA159 (79.81 %, 67.76 % and 56.31 %) and S. mutans SDC-05 (77.00 %, 59.48 % and 48.22 %) at the lowest concentration of 0.2, 0.1, 0.05 mg/ml. 4-H-3-MB did not inhibit bacterial growth even at concentrations 0.2 mg/ml. Similarly, 4-H-3-MB led to significant attrition in exopolysaccharide (EPS) and acid production by S. mutans UA159 and S. mutans (SDC-05) at the concentration of 0.2, 0.1 mg/ml, respectively. Optical microscopy and FE-SEM analysis 4-H-3-MB reduced the biofilm thickness of S. mutans UA159 and S. mutans SDC-05 relative to the untreated specimens.

CONCLUSION

4-H-3-MB significantly inhibited biofilm formation by S. mutans in a dose-dependent manner. Hence, our findings indicate that the active principle of 4-H-3-MB could be used as a biofilm inhibiting agent against S. mutans.

White Spot Lesions in Fixed Orthodontics: A Literature Review on Etiology, Prevention, and Treatment

White spot lesions (WSLs) are a common complication after treatment using fixed orthodontic appliances. Decalcification of enamel surrounding fixed orthodontic appliances, known as WSLs, poses a significant aesthetic difficulty during and after treatment, as the purpose of fixed orthodontic therapy is to improve facial and dental appearance. Modern dentistry utilizes remineralization therapies to non-invasively treat WSLs to prevent the progression of disease and enhance the strength, appearance, and functionality of the affected tooth. This review aims to identify and assess the etiology, formation, and risk factors, as well as current treatment approaches used in achieving WSLs remineralization, induced by fixed orthodontic appliances. An electronic search on the PubMed and ScienceDirect databases was performed using a selected keyword. A total of 172 studies (from 2013 to 2023) were retrieved. Their references were also checked to find other relevant studies. Duplicate copies were excluded. After the abstract and full-text screening, only 39 studies were included. Even though numerous studies address the different treatment modalities for managing post-orthodontic WSLs, such as antiseptics; fluorides such as dentifrices, mouthwash, and varnish, and remineralizing agents such as casein phosphopeptides amorphous calcium phosphate, biomimetic self-assembling peptides, lasers, bleaching, microabrasion, and resin infiltration. There is a lack of evidence-based studies that examine the long-term effects of WSL treatment. Further well-performed controlled clinical trials with long-term follow-up are needed to establish best clinical practice.

Chlorhexidine digluconate mouthwash alters the oral microbial composition and affects the prevalence of antimicrobial resistance genes

Introduction

Chlorhexidine (CHX) is a commonly used antiseptic in situations of limited oral hygiene ability such as after periodontal surgery. However, CHX is also considered as a possible factor in the emergence of cross-resistance to antibiotics. The aim of this study was to analyze the changes in the oral microbiota and the prevalence of antimicrobial resistance genes (ARGs) due to CHX treatment.

Materials and methods

We analyzed the oral metagenome of 20 patients who applied a 0.2% CHX mouthwash twice daily for 4 weeks following periodontal surgical procedures. Saliva and supragingival plaque samples were examined before, directly after 4 weeks, and another 4 weeks after discontinuing the CHX treatment.

Results

Alpha-diversity decreased significantly with CHX use. The Bray-Curtis dissimilarity increased in both sample sites and mainly streptococci showed a higher relative abundance after CHX treatment. Although no significant changes of ARGs could be detected, an increase in prevalence was found for genes that encode for tetracycline efflux pumps.

Conclusion

CHX treatment appears to promote a caries-associated bacterial community and the emergence of tetracycline resistance genes. Future research should focus on CHX-related changes in the microbial community and whether the discovered tetracycline resistance genes promote resistance to CHX.

Lethal puncturing of planktonic Gram-positive and Gram-negative bacteria by magnetically-rotated silica hexapods

Planktonic bacterial presence in many industrial and environmental applications and personal health-care products is generally countered using antimicrobials. However, antimicrobial chemicals present an environmental threat, while emerging resistance reduces their efficacy. Suspended bacteria have no defense against mechanical attack. Therefore, we synthesized silica hexapods on an α-Fe2O3 core that can be magnetically-rotated to inflict lethal cell-wall-damage to planktonic Gram-negative and Gram-positive bacteria. Hexapods possessed 600 nm long nano-spikes, composed of SiO2, as shown by FTIR and XPS. Fluorescence staining revealed cell wall damage caused by rotating hexapods. This damage was accompanied by DNA/protein release and bacterial death that increased with increasing rotational frequency up to 500 rpm. Lethal puncturing was more extensive on Gram-negative bacteria than on Gram-positive bacteria, which have a thicker peptidoglycan layer with a higher Young's modulus. Simulations confirmed that cell-wall-puncturing occurs at lower nano-spike penetration levels in the cell walls of Gram-negative bacteria. This approach offers a new way to kill bacteria in suspension, not based on antimicrobial chemicals.

The effect of daily usage of Listerine Cool Mint mouthwash on the oropharyngeal microbiome: a substudy of the PReGo trial

Introduction. ListerineÒ is a bactericidal mouthwash widely used to prevent oral health problems such as dental plaque and gingivitis. However, whether it promotes or undermines a healthy oral microbiome is unclear.Hypothesis/Gap Statement. We hypothesized that the daily use of Listerine Cool Mint would have a significant impact on the oropharyngeal microbiome.Aim. We aimed to assess if daily usage of Listerine Cool Mint influenced the composition of the pharyngeal microbiome.Methodology. The current microbiome substudy is part of the Preventing Resistance in Gonorrhoea trial. This was a double-blind single-centre, crossover, randomized controlled trial of antibacterial versus placebo mouthwash to reduce the incidence of gonorrhoea/chlamydia/syphilis in men who have sex with men (MSM) taking HIV pre-exposure prophylaxis (PrEP). Fifty-nine MSM taking HIV PrEP were enrolled. In this crossover trial, participants received 3 months of daily Listerine followed by 3 months of placebo mouthwash or vice versa. Oropharyngeal swabs were taken at baseline and after 3 months use of each mouthwash. DNA was extracted for shotgun metagenomic sequencing (Illumina Inc.). Non-host reads were taxonomically classified with MiniKraken and Bracken. The alpha and beta diversity indices were compared between baseline and after each mouthwash use. Differentially abundant bacterial taxa were identified using ANOVA-like differential expression analysis.Results. Streptococcus was the most abundant genus in most samples (n = 103, 61.7 %) with a median relative abundance of 31.5% (IQR 20.6-44.8), followed by Prevotella [13.5% (IQR 4.8-22.6)] and Veillonella [10.0% (IQR 4.0-16.8)]. Compared to baseline, the composition of the oral microbiome at the genus level (beta diversity) was significantly different after 3 months of Listerine (P = 0.006, pseudo-F = 2.29) or placebo (P = 0.003, pseudo-F = 2.49, permutational multivariate analysis of variance) use. Fusobacterium nucleatum and Streptococcus anginosus were significantly more abundant after Listerine use compared to baseline.Conclusion. Listerine use was associated with an increased abundance of common oral opportunistic bacteria previously reported to be enriched in periodontal diseases, oesophageal and colorectal cancer, and systemic diseases. These findings suggest that the regular use of Listerine mouthwash should be carefully considered.

Management of oral aphthous ulcer: A review

Aphthous ulcers, also known as canker sores, are a common oral condition characterized by recurrent, painful, small ulcers that typically arise on the non-keratinized mucous membranes within the mouth. Although the pathogenesis of aphthous ulcers is not completely understood; it is believed to be involved in a combination of genetic predisposition, local trauma, stress, hormonal changes, and certain environmental factors. Thus, management of aphthous ulcer revolves around reducing pain, promoting healing and preventing recurrence.

Patent Mining on the Use of Antioxidant Phytochemicals in the Technological Development for the Prevention and Treatment of Periodontitis

Periodontal disease is an inflammatory condition characterized by an aberrant immune response against a dysbiotic dental biofilm, with oxidative stress performing an essential role in its pathogenesis. This paper presents a patent mining, performed in the Orbit Intelligence patent database, related to antioxidant phytochemicals in the technological developments that are working to prevent and treat periodontal disease. To access the documents, the descriptors "PERIODONTAL" and "ANTIOXIDANT" were typed in the title, abstract, and claim search fields. A total of 322 patents demonstrate the growing interest in researching natural antioxidants for scientific and technological purposes. The top ten countries regarding the number of family patents produced were the United States, the European Office, Japan, South Korea, China, India, Mexico, Denmark, Canada, and Great Britain. The most cited compounds were vitamin C, green tea, quercetin, melatonin, lycopene, resveratrol, and curcumin. These compounds have been used for the technological development of gels, membranes, dentifrices, chewing gum, orally disintegrating film, mouthwash, mouth spray, and mouth massage cream and exhibit the ability to neutralize free radicals and reduce oxidative stress, a critical factor in the development and progression of periodontal diseases. The patent documents have shown that using antioxidant compounds in conjunction with traditional periodontal treatments is a promising area of interest in periodontal therapy.

In Vitro Study of Tensile Strength Comparison of Selected Nonabsorbable and Absorbable Suture Materials after Immersion in 0.12% Chlorhexidine Gluconate

Aim

To compare the tensile strength (TS) of absorbable and nonabsorbable suture materials after immersion in 0.12% chlorhexidine gluconate.

Materials and Methods

Six 4-0-gauge suture materials were used, namely silk (S), polypropylene (PP), polyamide 6 (PA6), polyglactin 910 (PG910), poliglecaprone 25 (PL25), and polydioxanone (PDX). A total of 540 suture materials were divided equally (90) into six groups and tested. These materials were divided into a nonimmersed condition (10) and two thermostatically controlled immersion media (40 each), using artificial saliva for the control group (CG) and 0.12% chlorhexidine gluconate for the test group (TG). The specimens were tied to prefabricated rubber rods before immersion and removed at the testing timepoint. By using a universal testing machine (Instron 5566) with hooks attached, a hook-mounted specimen TS testing was performed on days 0, 1, 3, 7, and 14 at a 10 mm/min crosshead speed until the material was stretched to failure, and the maximum TS was recorded in Newtons (N). The continuous variables were taken as the mean and standard deviation across the six study groups to assess the significance at α = 0.05. A two-factor analysis of variance (ANOVA) was performed to assess the TSs over time in different media. A Bonferroni correction was performed when the data were statistically significant according to a two-factor ANOVA. Intragroup statistical comparisons were performed by repeated ANOVA for each study group. All data were analyzed using SPSS 26.

Results

The suture material TS analysis showed that nonabsorbable suture materials maintained their TS throughout the study; silk exhibited different behaviors, decreasing in TS from baseline to day 1 and maintaining its TS until day 14. All absorbable suture materials decreased in TSs by day 14. The silk and PG910 samples in the TG performed significantly better than those in the CG.

Conclusions

Prescribing 0.12% chlorhexidine gluconate as a postsurgical mouth rinse is safest when silk and PG910 are the optimal suture materials.

Herbal Composite Preparation and Investigating its Efficiency to Inhibit Biofilm Formation and Virulence Factors of Prevotella Intermedia and Porphyromonas Gingivalis - Formulation of Mouthwash Using a Herbal Composite and Evaluating its Anti-microbial Activity

Herbal composite preparation was studied with the aim of inhibiting the virulence factors of two dental pathogens: Prevotella intermedia and Porphyromonas gingivalis. A novel herbal composite was developed using the herbal extracts of Wrightia tinctoria and Bauhinia variegata. During the study, the following observations were noted. The minimal inhibitory concentration of Wrightia tinctoria and Bauhinia variegata composites (WBc) was obtained for the test concentration of 20 μg/ml (16 ± 0.57 mm and 15 ± 0.75 mm of inhibitory zones against Prevotella intermedia and Porphyromonas gingivalis, respectively). Biofilm inhibition assay results revealed about 0.51 ± 1.25 mg/ml and 0.53 ± 0.57 mg/ml of minimal biofilm eradication concentration (MBEC) against Prevotella intermedia and Porphyromonas gingivalis, respectively. The effect of WBc on lactic acid production showed that 200 μg/ml and 400 μg/ml concentrates reduced up to 80% and 70% in Prevotella intermedia and Porphyromonas gingivalis, respectively. Formulated herbal mouthwash showed good stability under all three different test conditions (5°C, 25°C, and 40°C) as the color, odor, phase separation, and homogeneity were not changed for the period of 3 months. The anti-bacterial activity of formulated mouthwash (30 μg/ml) exhibited maximum inhibitory zones of about 18 ± 0.75 mm and 19 ± 1.05 mm against the respective test bacteria - Prevotella intermedia and Porphyromonas gingivalis. Amplification of mfa1 and clpB genes showed 246 bp and 294 bp fragments of P. gingivalis and 238 bp and 280 bp fragments of P. intermedia during agarose electrophoretic analysis. The docking report revealed -5.84 Kcal/Mol binding energy and found three hydrogen bonding between the quercetin and target protein, mfa1 of Porphyromonas gingivalis. The target protein, clpB of Prevotella intermedia, and quercetin had -6.72 Kcal/Mol binding energy and found four hydrogen bonds between them. The developed composite could be optimized in future to develop a novel and biocompatible herbal mouthwash for the prevention of different dental caries and gingival inflammation associated with dental biofilm formation.

Preparation and properties of a 3D printed nHA/PLA bone tissue engineering scaffold loaded with a β-CD-CHX combined dECM hydrogel

Jaw defects, which can result from a multitude of causes, significantly affect the physical well-being and psychological health of patients. The repair of these infected defects presents a formidable challenge in the clinical and research fields, owing to their intricate and diverse nature. This study aims to develop a personalized bone tissue engineering scaffold that synergistically offers antibacterial and osteogenic properties for treating infected maxillary defects. This study engineered a novel temperature-sensitive, sustained-release hydrogel by amalgamating β-cyclodextrin (β-CD) with chlorhexidine (CHX) and a decellularized extracellular matrix (dECM). This hydrogel was further integrated with a polylactic acid (PLA)-nano hydroxyapatite (nHA) scaffold, fabricated through 3D printing, to form a multifaceted composite scaffold (nHA/PLA/dECM/β-CD-CHX). Drug release assays revealed that this composite scaffold ensures prolonged and sustained release. Bacteriological studies confirmed that the β-CD-CHX loaded scaffold exhibits persistent antibacterial efficacy, thus effectively inhibiting bacterial growth. Moreover, the scaffold demonstrated robust mechanical strength. Cellular assays validated its superior biocompatibility, attributed to dECM and nHA components, significantly enhancing the proliferation, adhesion, and osteogenic differentiation of osteogenic precursor cells (MC3T3-E1). Consequently, the nHA/PLA/dECM/β-CD-CHX composite scaffold, synthesized via 3D printing technology, shows promise in inducing bone regeneration, preventing infection, and facilitating the repair of jaw defects, positioning itself as a potential breakthrough in bone tissue engineering.

Efficacy of adjunctive octenidine hydrochloride as compared to chlorhexidine and placebo as adjuncts to instrumentation in stage I-II periodontitis: A double-blinded randomized controlled trial

OBJECTIVES

This randomized, controlled, double-blinded clinical trial aimed to evaluate the efficacy of octenidine hydrochloride and chlorhexidine mouthwashes as adjuncts to instrumentation in stage I-II periodontitis patients.

METHODS

Forty-five patients with mild-to-moderate periodontitis were randomly allocated to three groups: 0.1% octenidine dihydrochloride (OCT), placebo, and 0.12% chlorhexidine (CHX) mouthwashes. Patients were instructed to use the mouthwash after instrumentation for twice a day up to 3 weeks. Periodontal parameters such as probing pocket depth (PPD), clinical attachment loss (CAL), O'Leary plaque index (PI), Loe and Silness gingival index (GI), Lobene stain index (SI), and oral soft tissue changes were recorded at baseline and once every week for 3 weeks. The visual analogue scale (VAS) was also recorded as a self-administered questionnaire at the end of the study. The one-way ANOVA was used to compare VAS scores between the groups. The repeated measures ANOVA and post hoc Newman-Keuls tests were used to assess the differences in the periodontal parameters between groups at different time intervals. The Kruskal-Wallis test was used to compare the mean SI.

RESULTS

There was a significant reduction in the mean GI of the OCT and CHX groups compared to placebo (p < 0.05). OCT usage resulted in significantly less staining, according to mean SI, when compared to CHX. Furthermore, VAS scores revealed that OCT was significantly the preferred mouthwash (p < 0.01).

CONCLUSION

Adjunctive octenidine hydrochloride may be an alternative to chlorhexidine in its ability to control the periodontal parameters in patients with stage I-II periodontitis. Further larger studies are necessary to confirm these findings.

Inhibitory and preventive effects of Arnebia euchroma (Royle) Johnst. root extract on Streptococcus mutans and dental caries in rats

BACKGROUND

Dental caries is one of the prevalent conditions that threaten oral health. Arnebia euchroma (Royle) Johnst. root (AR) extracts exhibit anti-inflammatory, anti-cancer, and antibacterial properties. This study was designed to investigate the antibacterial impact of AR extract on Streptococcus mutans (S. mutans) UA159 and the anti-caries effect on rats.

METHODS

The antibacterial activity of AR extract against S. mutans and its biofilm was determined using the bacterial sensitivity test, the biofilm sensitivity test, and the live-dead staining technique. By fluorescently tagging bacteria, the influence of bacterial adhesion rate was determined. Using a rat caries model, the anti-caries efficacy and safety of AR extract were exhaustively investigated in vivo.

RESULTS

AR extract inhibit not only the growth of S. mutans, but also the generation of S. mutans biofilm, hence destroying and eliminating the biofilm. Moreover, AR extract were able to inhibit S. mutans' adherence to saliva-encapsulated hydroxyapatite (HAP). Further, in a rat model of caries, the AR extract is able to greatly reduce the incidence and severity of caries lesions on the smooth surface and pit and fissure of rat molars, while exhibiting excellent biosafety.

CONCLUSIONS

AR extract exhibit strong antibacterial activity against S. mutans and can lower the incidence and severity of dental cavities in rats. These findings suggest that Arnebia euchroma (Royle) Johnst. could be utilized for the prevention and treatment of dental caries.

Electrolyzed Saline Targets Biofilm Periodontal Pathogens In Vitro

Preventing the development and recurrence of periodontal diseases often includes antimicrobial mouthrinses to control the growth of the periodontal pathogens. Most antimicrobials are nonselective, targeting the symbiotic oral species as well as the dysbiosis-inducing ones. This affects the overall microbial composition and metabolic activity and consequently the host-microbe interactions, which can be detrimental (associated with inflammation) or beneficial (health-associated). Consequently, guiding the antimicrobial effect for modulating the microbial composition to a health-associated one should be considered. For such an approach, this study investigated electrolyzed saline as a novel rinse. Electrolyzed saline was prepared from sterile saline using a portable electrolysis device. Multispecies oral homeostatic and dysbiotic biofilms were grown on hydroxyapatite discs and rinsed daily with electrolyzed saline (EOS). Corresponding positive (NaOCl) and negative (phosphate-buffered saline) controls were included. After 3 rinses, biofilms were analyzed with viability quantitative polymerase chain reaction and scanning electron microscopy. Supernatants of rinsed biofilms were used for metabolic activity analysis (high-performance liquid chromatography) through measuring organic acid content. In addition, human oral keratinocytes (HOKs) were exposed to EOS to test biocompatibility (cytotoxicity and inflammation induction) and also to rinsed biofilms to assess their immunogenicity after rinsing. Rinsing the dysbiotic biofilms with EOS could reduce the counts of the pathobionts (>3 log10 Geq/mm2 reduction) and avert biofilm dysbiosis (≤1% pathobiont abundance), leading to the dominance of commensal species (≥99%), which altered both biofilm metabolism and interleukin 8 (IL-8) induction in HOKs. EOS had no harmful effects on homeostatic biofilms. The scanning electron micrographs confirmed the same. In addition, tested concentrations of EOS did not have any cytotoxic effects and did not induce IL-8 production in HOKs. EOS showed promising results for diverting dysbiosis in in vitro rinsed biofilms and controlling key periopathogens, with no toxic effects on commensal species or human cells. This novel rinsing should be considered for clinical applications.

Epigallocatechin gallate-immobilized antimicrobial resin with rechargeable fluorinated synergistic composite for enhanced caries control

OBJECTIVES

Given the global prevalence of dental caries, impacting 2.5 billion individuals, the development of sophisticated prevention filling materials is crucial. Streptococcus mutans, the principal caries-causing strain, produces acids that demineralize teeth and initiate dental caries. To address this issue, we aimed to develop a synergistic resin-based composite for enhancing caries control.

METHODS

The synergistic resin composite incorporates fluorinated kaolinite and silanized Al2O3 nanoparticle fillers into an epigallocatechin gallate (EGCG) immobilized urethane-modified epoxy acrylate (U-EA) resin matrix, referred to the as-prepared resin composite. The EGCG-modified TPGDA/U-EA network was synthesized by preparing methacrylate-functionalized isocyanate (HI), reacting it with EGCG to form HI-EGCG, and then incorporating HI-EGCG into the TPGDA/U-EA matrix. The lamellar space within the kaolinite layer was expanded through the intercalation of acrylamide into kaolinite, enhancing its capability to adsorb and release fluoride ions (F-). The layered structure of acrylamide/ kaolinite in the U-EA resin composite acts as a F- reservoir.

RESULTS

The physico-mechanical properties of the as-prepared resin composites are comparable to those of commercial products, exhibiting lower polymerization shrinkage, substantial F- release and recharge and favorable diametral tensile strength. The immobilized EGCG in the composite exhibits potent antimicrobial properties, effectively reducing the biofilm biomass. Furthermore, the synergistic effect of EGCG and fluorinated kaolinite efficiently counteracts acid-induced hydroxyapatite dissolution, thereby suppressing demineralization and promoting enamel remineralization.

SIGNIFICANCE

Our innovative EGCG and fluoride synergistic composite provides enhanced antimicrobial properties, durable anti-demineralization, and tooth remineralization effects, positioning it as a promising solution for effective caries control and long-term dental maintenance.

Effectiveness of Glutamine Oral Care in Reducing Oral Mucositis and Improving Oral Health After Neurosurgery: A Randomized Controlled Trial with Microbiome Analysis

BACKGROUND Hospital-acquired infections negatively impact the health of inpatients and are highly costly to treat. Oral care reduces the microorganism number in the mouth and lungs and is essential in preventing postoperative oral inflammation, lung infection, and other complications. This study was designed to determine the effects of oral care with glutamine on oral health, oral flora, and incidence of pneumonia in patients after neurosurgery. MATERIAL AND METHODS This was a parallel, double-blind, randomized trial. Patients admitted to the Neurosurgery Department of the hospital from July to October 2021 were selected. Three hundred patients who met the inclusion criteria were randomized into 3 groups. The control group (n=100) received oral care with routine oral nursing methods with saline, whereas the experimental group (n=100) received oral care with 5% glutamine. A compound chlorhexidine group (n=100) was set as a positive control. All patients, care providers, and investigators were blinded to the group assignment. The incidence of local debris, oral mucositis, halitosis, dryness, oral mucositis disorders, and oral flora types were collected and analyzed in all groups. RESULTS The incidence of local debris, oral mucositis, halitosis, dryness, and other oral mucositis disorders in the glutamine oral care group was significantly decreased, compared with that of the control group. Oral flora types in the glutamine and chlorhexidine groups were significantly reduced. CONCLUSIONS Oral care with 5% glutamine after neurosurgery is associated with a lower incidence of oral disorders and pneumonia, and a significant reduction in oral flora.

Influence of Chairside Simulated Adjustment (Finishing and Polishing) Protocol and Chlorhexidine Mouthwash Immersion on Color Stability and Translucency of 2 and 3 Preshaded Multilayered Monolithic Zirconia

BACKGROUND Preshaded monolithic zirconia (MLZ) is reported to have high translucency. This study aimed to assess the effect of chlorhexidine gluconate (ChG) mouthwash on color and translucency parameter (TP) of 2 different preshaded MLZ dental ceramics after clinical adjustment. MATERIAL AND METHODS Two MLZ disk-shaped specimens [NPM (Nacera Pearl Multi-Shade) (n=72) and CZM (Ceramill Zolid FX Multilayer)] (n=72) were simulated for clinical adjustment, finished, and polished using 2 adjustment kits [recommended kit, third-party kit: Diasynt Plus and SUN (n=12 each)] and later immersed in ChG mouthwash (Avohex) for 2 weeks. Difference in color (ΔE) and TP (Y) were calculated using the CIELab formula after measuring the coordinates (Lab) with a colorimeter. Individual changes in color and TP were assessed on the Clinical acceptance (perceptible) threshold (CAT/CPT) and Translucency perception threshold (TPT), respectively. Differences between the 2 ceramics were assessed using one-way ANOVA and post hoc tests, with all differences considered significant at P<0.05. RESULTS NPM and CZM differed in color at baseline despite having the same Vita shade combination. Between the 2 preshaded MLZ ceramics, NPM showed significant changes in color when adjusted with a third-party kit. Chlorhexidine produced changes in color and TP that were designated as clinically perceptible (ΔE=1.0 to 3.3) on the CAT/CPT and TPT scales, irrespective of the adjustment kit used. ChG produced the least or no changes in glazed MLZ specimens. CONCLUSIONS ChG mouthwash, whenever prescribed for preshaded MLZ restoration, should be adjusted prior to final glazing to avoid clinical adjustments that adversely affects color and translucency of the restoration.

Effectiveness of Oroantral Communication Closure Using Solid Platelet-Rich Fibrin Compared to a Conventional Treatment Approach: A Randomized Clinical Trial

This study aimed to compare the effectiveness of platelet-rich fibrin clot (PRF) and conventional oroantral communication (OAC) repair techniques following tooth extractions from the maxilla. The study involved 22 patients, divided into 2 groups: a study group treated with PRF and a control group undergoing conventional OAC repair. The primary outcome measured was the effectiveness of OAC closure, with pain intensity and postoperative complications as secondary outcomes. Cone-beam computed tomography (CBCT) was used to evaluate post-extraction bone regeneration. Pain was assessed using the Visual Analogue Scale (VAS) on days 0, 1, 7, and 14 postoperatively. The results showed that the PRF group experienced a significant decrease in pain within the first 24 hours and after 7 days (P < .0001; P < .05). In contrast, complications were reported in 45.45% of patients in the conventional repair group and 18.18% in the A-PRF group. Three months postsurgery, CBCT revealed appreciable bone healing in both groups, with no significant difference (P > .05). In conclusion, the study suggests that A-PRF treatment for OACs resulted in fewer complications and quicker pain reduction than traditional repair methods, making it a promising alternative for managing OACs. However, future studies are needed to confirm these findings and establish the full therapeutic potential of PRF.

Effects of Oil Pulling and Chlorhexidine Mouth Rinse on the Force Decay of Orthodontic Elastomeric Chains: A Comparative In Vitro Study

BACKGROUND AND OBJECTIVES

Oil pulling is a traditional Indian folk remedy for maintaining oral hygiene among orthodontic patients. This study aimed to assess the effects of oil pulling and compare them with those of chlorhexidine (CHX) and distilled water on the force decay of elastomeric chains.

METHODS

Twenty-one samples were tested in three groups. Each of these groups contained seven samples per group. The samples evaluated contained distilled water, 0.2% CHX, and sesame oil. The samples were dipped in various mouth rinses, and force degradation was measured using a dynamometer (dynamic universal testing machine, Instron 8801, Instron, Norwood, MA) during days 0, 1, 7, 14, 21, and 28. The significance level was considered at 1%.

RESULTS

Force degradation was observed more in distilled water, followed by sesame oil, and less in CHX at the end of 28 days. Significant differences in values (p < 0.01) were found among the three groups in all the timelines in the study except on days 14 and 21.

CONCLUSION

Chlorhexidine showed the least amount of force decay, followed by oil pulling and distilled water. However, if oil pulling is practiced daily as a household remedy along with regular oral hygiene practices, it can save time and money and enhance general health.

Proguanil and chlorhexidine augment the antibacterial activities of clarithromycin and rifampicin against Acinetobacter baumannii

The emergence of Acinetobacter baumannii infections as a significant healthcare concern in hospital settings, coupled with their association with poorer clinical outcomes, has prompted extensive investigation into novel therapeutic agents and innovative treatment strategies. Proguanil and chlorhexidine, both categorized as biguanide compounds, have displayed clinical efficacy as antimalarial and topical antibacterial agents, respectively. In this study, we conducted an investigation to assess the effectiveness of combining proguanil and chlorhexidine with clarithromycin or rifampicin against both laboratory strains and clinical isolates of A. baumannii. The combination therapy demonstrated rapid bactericidal activity against planktonic multidrug-resistant A. baumannii, exhibiting efficacy in eradicating mature biofilms and impeding the development of antibiotic resistance in vitro. Additionally, when administered in conjunction with clarithromycin or rifampicin, proguanil enhanced the survival rate of mice afflicted with intraperitoneal A. baumannii infections, and chlorhexidine expedited wound healing in mice with skin infections. These findings are likely attributable to the disruption of A. baumannii cell membrane integrity by proguanil and chlorhexidine, resulting in heightened membrane permeability and enhanced intracellular accumulation of clarithromycin and rifampicin. Overall, this study underscores the potential of employing proguanil and chlorhexidine in combination with specific antibiotics to effectively combat A. baumannii infections and improve treatment outcomes in clinically challenging scenarios.

The Antimicrobial Potential of the Hop (Humulus lupulus L.) Extract against Staphylococcus aureus and Oral Streptococci

Plant extracts are in the focus of the pharmaceutical industry as potential antimicrobials for oral care due to their high antimicrobial activity coupled with low production costs and safety for eukaryotic cells. Here, we show that the extract from Hop (Humulus lupulus L.) exhibits antimicrobial activity against Staphylococcus aureus and Streptococci in both planktonic and biofilm-embedded forms. An extract was prepared by acetone extraction from hop infructescences, followed by purification and solubilization of the remaining fraction in ethanol. The effect of the extract on S. aureus (MSSA and MRSA) was comparable with the reference antibiotics (amikacin, ciprofloxacin, and ceftriaxone) and did not depend on the bacterial resistance to methicillin. The extract also demonstrated synergy with amikacin on six S. aureus clinical isolates, on four of six isolates with ciprofloxacin, and on three of six isolates with ceftriaxone. On various Streptococci, while demonstrating lower antimicrobial activity, an extract exhibited a considerable synergistic effect in combination with two of three of these antibiotics, decreasing their MIC up to 512-fold. Moreover, the extract was able to penetrate S. aureus and S. mutans biofilms, leading to almost complete bacterial death within them. The thin-layer chromatography and LC-MS of the extract revealed the presence of prenylated flavonoids (2',4',6',4-tetrahydroxy-3'-geranylchalcone) and acylphloroglucides (cohumulone, colupulone, humulone, and lupulone), apparently responsible for the observed antimicrobial activity and ability to increase the efficiency of antibiotics. Taken together, these data suggest an extract from H. lupulus as a promising antimicrobial agent for use both as a solely antiseptic and to potentiate conventional antimicrobials.

Association of Papacarie Duo® and low-level laser in antimicrobial photodynamic therapy (aPDT)

Dental caries is a multifactorial, non-communicable disease. Effective treatment options for minimally invasive removal of carious tissue include Papacarie Duo® gel and antimicrobial photodynamic therapy (aPDT). aPDT involves a combination of a light source and photosensitizer. Given that Papacarie Duo® contains a percentage of blue dye, this study aims to explore the antimicrobial potential of Papacarie Duo® when associated with a light source against Streptococcus mutans strains. The chosen light source was a low-power diode laser (λ = 660 nm, E = 3 J, P = 100 mW, t = 30 s). To assess antimicrobial capacity, planktonic suspensions of Streptococcus mutans were plated on Brain Heart Infusion Agar (BHI) to observe the formation of inhibition halos. The studied groups included methylene blue (0.005%), Papacarie Duo®, distilled water (negative control), 2% chlorhexidine (positive control), Papacarie Duo® + laser, and methylene blue (0.005%) + laser. Following distribution onto plates, each group was incubated at 37 °C for 48 h under microaerophilic conditions. Inhibition halos were subsequently measured using a digital caliper. The results showed that chlorhexidine had the greatest antimicrobial effect followed by the group of irradiated methylene blue and irradiated Papacarie Duo®. All experimental groups demonstrated antimicrobial potential, excluding the negative control group. The study concludes that Papacarie Duo® exhibits antimicrobial properties when associated with a low-power diode laser.

Periodontal disease in down syndrome: Predisposing factors and potential non-surgical therapeutic approaches

BACKGROUND

Periodontal diseases (PDs) have been documented to be significantly more prevalent and severe in patients with Down syndrome (DS). Different immunological and microbiological factors contributed to predisposing these patients to progressive and recurrent PDs.

AIM

The aim of this review was to investigate the altered immunological responses and oral microbiota disorders as well as focus on adjunctive non-surgical methods for the treatment of PDs and its applicability in patients with DS.

MATERIAL AND METHODS

A literature review was conducted addressing the following topics: (1) the altered immunological responses, (2) orofacial disorders related to DS patients, (3) oral microbiota changing, and (4) adjunctive non-surgical treatment and its efficacy in patients with DS.

RESULTS

Due to the early onset of PDs in children with DS, the need for prompt and effective treatment in these patients is essential.

DISCUSSION AND CONCLUSION

So, investigating underlying factors may open a new window to better understand the pathology of PDs in DS people and thus, find better strategies for treatment in such group. Although non-surgical treatments such as photodynamic therapy and probiotic consumption represented acceptable outcomes in different examined patients without DS, data about the application of these convenience and no need for local anesthesia methods in patients with DS is limited.

Effect of curcumin, betadine and chlorhexidine in gingival wound healing

The effect of chlorhexidine (CHX) digluconate, Betadine (BET), curcumin (CUR) on gingival wound healing is of interest to dental practitioners. Hence, we studied the average fibroblast viability % for each of the concentrations of CUR, BET and CHX over various time durations. It was found that mean percentage of viability of fibroblasts is high in CUR and low in CHX at all time periods while the mean percentage of viability of fibroblasts in BET 1% was greater than CHX but lower than CUR at all time periods. Thus, curcumin at a concentration of 0.003% demonstrates the least cytotoxicity for fibroblasts. Hence, it is the most effective bacterial suppression, and the best wound healing.

Effect of Commercial Children's Mouthrinses and Toothpastes on the Viability of Neonatal Human Melanocytes: An In Vitro Study

In this study, we examined the cytotoxic effects of six commercial children's mouthrinses (designated as #1, #2, #3, #4, #5, and #6) and four commercial children's toothpastes (designated as #1, #2, #3, and #4) on primary human neonatal melanocytes that were used as a representative model for oral melanocytes. Mouthrinses diluted directly with culture medium (1:2, 1:5, 1:10, 1:100, and 1:1000) were added to monolayers of melanocytes for 2 min, followed by 24 h recovery, after which MTS cytotoxicity assay was conducted. The extracts of each toothpaste were prepared (50% w/v), diluted in culture medium (1:2, 1:5, 1:10, 1:50, 1:100, and 1:1000), and added to cell monolayers for 2 min (standard brushing time), followed by an analysis of cell viability after 24 h. Results showed that all mouthrinses except mouthrinse #4 showed significantly greater loss of cell viability, ascribed to cetylpyridinium chloride (CPC) that induced significant cytotoxicity to melanocytes (IC50 = 54.33 µM). In the case of toothpastes, the examination of cellular morphology showed that a 2 min exposure to all toothpaste extracts induced a concentration-dependent decline in cell viability, pronounced in toothpaste containing sodium lauryl sulfate (SLS) detergent. Further results suggested SLS to be the critical driver of cytotoxicity (IC50 = 317.73 µM). It is noteworthy that toothpaste #1 exhibited much lower levels of cytotoxicity compared to the other three toothpastes containing SLS. Taken together, these findings suggest that the melanocytotoxicity of children's mouthrinse (#4) and toothpaste (#1) is comparatively low. To the best of our knowledge, this is the first study to examine the impact of children's toothpastes and mouthrinses on neonatal primary human melanocytes. Future studies to investigate these findings in a realistic scenario replicating oral cavity conditions of the presence of microbiota, pellicle layer and saliva, and other cell types are warranted.

Pudilan Keyanning mouthwash inhibits dextran-dependent aggregation and biofilm organization of Streptococcus mutans

AIMS

This research aimed to investigate the inhibitory effects of Pudilan mouthwash (PDL) on Streptococcus mutans (S. mutans) biofilms and identify its chemical components.

METHODS AND RESULTS

The impacts of 100% concentrated PDL on S. mutans biofilm were detected by colony-forming unit (CFU) assays, crystal violet staining, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and quantitative real-time PCR (qRT‒PCR). The biocompatibility with human gingival fibroblasts (HGFs) was evaluated by Cell-Counting-Kit-8 (CCK-8) assay. And chemical components were identified by UPLC-HRMS. PBS and 0.12% chlorhexidine were used as negative and positive controls, respectively. Results indicate early 8-h S. mutans biofilms are sensitive to PDL. Additionally, it leads to a decrease in bacterial activities and dextran-dependent aggregation in 24-h S. mutans biofilms. PDL significantly downregulates the gene expression of gtfB/C/D and smc. And 114 components are identified.

CONCLUSIONS

PDL has an inhibitory effect on S. mutans and favorable biocompatibility. It has potential to be exploited as a novel anti-biofilm agent.

Changes in oral microflora following 0.3% cetylpyridinium chloride-containing mouth spray intervention in adult volunteers after professional oral care: Randomized clinical study

OBJECTIVES

This study explored the changes in bacterial flora composition and total bacterial count in the saliva and tongue coating, along with the change in the tongue coating index (TCI) following an intervention with 0.3% cetylpyridinium chloride (CPC) mouth spray after professional oral care.

MATERIALS AND METHODS

Fifty-two adult volunteers aged 30-60 years were equally divided into CPC spray (n = 26) and control (n = 26) groups. All subjects underwent scaling and polishing. The CPC spray group was administered four puffs of CPC spray to the tongue dorsum four times a day for 3 weeks. The control group performed only routine daily oral care (brushing) and did not use any other spray. Bacteriological evaluation of saliva and tongue coating was performed using 16S ribosomal RNA gene sequencing and quantitative polymerase chain reaction. The tongue coating was evaluated to calculate the TCI. A per-protocol analysis was conducted for 44 subjects (CPC spray group, n = 23; control group, n = 21).

RESULTS

At 1 and 3 weeks after CPC spray use, the flora of the saliva and tongue coating changed; the genus Haemophilus was dominant in the CPC spray group, whereas the genus Saccharibacteria was dominant in the control group. The sampling time differed among individual participants, which may have affected the bacterial counts. There was no significant intragroup change in TCI in either group.

CONCLUSIONS

CPC spray affected the bacterial flora in the saliva and tongue coating, particularly with respect to an increase in the abundance of Haemophilus. However, CPC spray did not change the TCI. These results suggest that it may be optimal to combine CPC spray with a physical cleaning method such as using a tongue brush or scraper. Clinical Trial Registration: University Hospital Medical Information Network UMIN000041140.

Factorial design of in situ gelling two-compartment systems containing chlorhexidine for the treatment of periodontitis

Periodontitis is one of the most widespread bacterial infectious oral diseases that affects a significant percentage of the population worldwide. Different bacterial strains are responsible for the chronic inflammation and subgingival plaque that could be effectively treated with prolonged exposure to therapeutic levels of antibiotics and antiseptics in the periodontal pockets. Medicated in situ gels of chlorhexidine (CHX), for extended drug release and long-lasting antiseptic effect in the targeted cavities, were prepared in a two-compartment system. One compartment was loaded with sodium alginate solution while other was filled with CHX and calcium solution. The mixing of the solutions during the application resulted in gelation. Two 33 full factorial designs were applied in this study in order to optimize the gel formulation. Initially, the effects of concentration of gelling agent, crosslinker, and pH of the system on the dependent variables such as gel formation and structure characteristics were investigated. Then, the concentration of the crosslinker was optimized. Afterwards, the effect of gelling agent, loading of the drug, and pH of the gel system were correlated with the gel characteristics through another factorial design. Optimized formulations were tested for mucoadhesion, in vitro drug release, and microbiological investigation. Based on the results of the factorial design, mucoadhesiveness, antimicrobial investigation, and drug release, a 4 % alginate composition can be considered optimal. Overall, the optimized in situ periodontal gel was found to be effective with prolonged retention time and desirable outcomes.

Comparative evaluation of effect of sodium hypochlorite and chlorhexidine in dental unit waterline on aerosolized bacteria generated during dental treatment

BACKGROUND

In dentistry, nosocomial infection poses a great challenge to clinicians. The microbial contamination of water in dental unit waterlines (DUWLs) is ubiquitous. Such infected DUWLs can transmit oral microbes in the form of aerosols. Previous studies have suggested treating DUWLs with various disinfectants to reduce cross-contamination. The literature lacks a comparative evaluation of the effect of the use of 0.2% chlorhexidine (CHX) and 0.1% sodium hypochlorite (NaOCl) in DUWLs on aerosolized bacteria generated during dental procedures.

OBJECTIVE

To compare the effect of NaOCl and CHX in DUWLs on aerosolized bacteria generated during restorative and endodontic procedures.

MATERIALS AND METHODS

A total of 132 patients were equally divided into three groups (n = 44 in each group) according to the content of DUWL as follows. Group I-0.1% NaOCl Group II-0.2% CHX Group III-distilled water (Positive control) One-way ANOVA was performed and the Kruskal-Wallis test was used for intergroup comparison.

RESULTS

For the restorative procedure, inter-group comparison of mean colony-forming units (CFU) scores showed a statistically significant difference between the groups (p - .001) with the score of group 3 higher than group 2 followed by group 1. For the endodontics, an inter-group comparison of CFU scores showed a statistically significant difference between the groups (p - .003) with the mean score in group 1 being the lowest and group 3 being the highest.

CONCLUSION

The addition of NaOCl or CHX in DUWLs shows an effective reduction in aerosolized bacteria compared to distilled water.

Assessment of in vitro efficacy for common surface disinfectants and antiseptics against Tritrichomonas foetus trophozoites

The protozoan Tritrichomonas foetus causes early embryonic death in cattle, there are no legal options for treating this parasite in the United States, and there are few developed protocols for cleaning veterinary and obstetrical equipment that may have been contaminated with trophozoites. In this study, we evaluated bleach, ethanol, acetic acid, chlorhexidine gluconate, and hydrogen peroxide solutions for the ability to kill trophozoites in vitro. Our findings suggested that ethanol and bleach could adequately disinfect tools and equipment. Acetic acid, chlorhexidine, and hydrogen peroxide had applications as surface disinfectants in addition to potential as local topical treatments due to their past uses in veterinary theriogenology. Chlorhexidine gluconate demonstrated trophocidal effects by damaging parasite cell membranes and had the lowest effective concentration 50 (EC50) of any compound tested and was in the micromolar range. These findings, in conjunction with accepted clinical uses of chlorhexidine gluconate suggest that this is a convenient agent for disinfecting equipment. In addition, topical use of chlorhexidine is relatively common, setting the stage for further investigation of this compound as a topical therapeutic option for bovine trichomonosis.

Evaluation of the Physicochemical and Antimicrobial Properties of Nanoemulsion-Based Polyherbal Mouthwash

A nanoemulsion-based polyherbal mouthwash (PHFX) of Curcuma longa hydroalcoholic extract was developed and evaluated for its antibacterial effects against a variety of Gram-positive and Gram-negative oral pathogens in comparison to standard chlorhexidine acetate (CHD-A) (positive control). Various nanoemulsion-based mouthwashes of C. longa extract were produced using an aqueous phase titration approach via construction of pseudoternary phase diagrams. The developed nanoemulsion-based PHFX was studied for thermodynamic stability tests. Selected formulations (PHFX1-PHFX5) were characterized physicochemically for droplet diameter, polydispersity index (PDI), refractive index (RI), transmittance, and pH. The drug release studies were performed using the dialysis method. Based on the minimum droplet diameter (26.34 nm), least PDI (0.132), optimal RI (1.337), maximum %T (99.13), optimal pH (6.45), and maximum cumulative drug release (98.2%), formulation PHFX1 (containing 0.5% w/w of C. longa extract, 1.5% w/w of clove oil, 7.0% w/w of Tween-80, 7.0% w/w of Transcutol-HP, and 84.0% w/w of water) was selected for antimicrobial studies in comparison to standard CHD-A. The antibacterial effects and minimum inhibitory concentration were studied against various Gram-positive oral pathogens such as Streptococcus mutans, Staphylococcus aureus, Streptococcus pneumoniae, and Bacillus subtilis and Gram-negative oral pathogens such as Escherichia coli and Klebsiella pneumoniae. The antibacterial effects of PHFX1 were found to be significant over standard CHD-A against most Gram-positive and Gram-negative oral pathogens. The antimicrobial studies showed that the formulation PHFX1 was effective against all oral pathogens even at 3- to 4-fold lower working concentrations. These findings indicated the potential of nanoemulsion-based mouthwash in the treatment of a variety of oral pathogen infections.

Antimicrobial Mouthwashes: An Overview of Mechanisms-What Do We Still Need to Know?

This narrative literature review is the first in a 6-section supplement on the role of mouthwashes in oral care. This introduction briefly summarises current knowledge on antimicrobial mechanisms, relating to some of the most common over-the-counter mouthwash products available worldwide: chlorhexidine, hydrogen peroxide, cetylpyridinium chloride, povidone iodine, and essential oils. The aim of this first article is to describe how mouthwashes "kill" pathogenic microbes when used adjunctively and thus provide a basis for their widespread use to manage key oral diseases, namely caries, gingivitis, and periodontal disease. This article therefore sets the scene for subsequent, more detailed exploration of mouthwashes regarding their clinical effectiveness, impact on the oral microbiome, and possible effects on systemic health as well as natural alternatives and future directions. Other than the clinical effectiveness (for certain agents) of mouthwashes, on many topics there remains insufficient evidence for systematic review or formulation of robust national guidelines. The supplement, therefore, compiled by an international task team, is aimed at general dental practitioners across the globe, as an easy-to-read guide for helping to advise patients on mouthwash use based on the current best available evidence.

Mechanisms of emerging resistance associated with non-antibiotic antimicrobial agents: a state-of-the-art review

Although the development of resistance by microorganisms to antimicrobial drugs has been recognized as a global public health concern, the contribution of various non-antibiotic antimicrobial agents to the development of antimicrobial resistance (AMR) remains largely neglected. The present review discusses various chemical substances and factors other than typical antibiotics, such as preservatives, disinfectants, biocides, heavy metals and improper chemical sterilization that contribute to the development of AMR. Furthermore, it encompasses the mechanisms like co-resistance and co-selection, horizontal gene transfer, changes in the composition and permeability of cell membrane, efflux pumps, transposons, biofilm formation and enzymatic degradation of antimicrobial chemicals which underlie the development of resistance to various non-antibiotic antimicrobial agents. In addition, the review addresses the resistance-associated changes that develops in microorganisms due to these agents, which ultimately contribute to the development of resistance to antibiotics. In order to prevent the indiscriminate use of chemical substances and create novel therapeutic agents to halt resistance development, a more holistic scientific approach might provide diversified views on crucial factors contributing to the persistence and spread of AMR. The review illustrates the common and less explored mechanisms contributing directly or indirectly to the development of AMR by non-antimicrobial agents that are commonly used.

Exploring the Antibacterial Potential of Konjac Glucomannan in Periodontitis: Animal and In Vitro Studies

Background and Objectives: Periodontitis is an inflammatory disease in the supporting tissues of the teeth caused by specific microorganisms or groups of microorganisms. P. gingivalis bacterium is the keystone pathogen in periodontitis, so even at low concentrations, it has a considerable influence on the oral community. Antimicrobials and antiplaque agents can be used as adjunctive therapy for periodontitis treatment. Konjac glucomannan (KGM), as a natural polysaccharide, has flavonoid (3,5-diacetyltambulin) and triterpenoids (ambylon) compounds that show antibacterial activity. This research aims to analyze the antibacterial activity of KGM on animal and in vitro periodontitis models. Materials and Methods: The animal study divided 48 mice into four groups (control, KGM, periodontitis, KGM + periodontitis). Mice were given an intervention substance by oral gavage from day 1 to day 14, periodontitis was induced on day 7, and decapitation was performed on day 14. Samples from the right maxillary jaw of mice were used for histological preparations and morphometrics analysis. In vitro studies were carried out by adding several concentrations of KGM (25, 50, and 100 μg/mL) into a planktonic P. gingivalis and P. gingivalis biofilm. Results: In the animal model, KGM could prevent alveolar bone loss in the periodontitis mice model, both in histologic and morphometrics assessments. In vitro, KGM had antibacterial activity against P. gingivalis with better bacteriostatic (15-23%) than bactericidal (11-20%) ability, proven by its ability to inhibit P. gingivalis proliferation. Conclusions: KGM can be considered to have the potential as an antibacterial agent to prevent periodontitis. The prevention of periodontitis may improve patient well-being and human quality of life.

Synergistic Antibiofilm Action of Cinnamomum verum and Brazilian Green Propolis Hydroethanolic Extracts against Multidrug-Resistant Strains of Acinetobacter baumannii and Pseudomonas aeruginosa and Their Biocompatibility on Human Keratinocytes

The accumulated dental biofilm can be a source of oral bacteria that are aspirated into the lower respiratory tract causing ventilator-associated pneumonia in hospitalized patients. The aim of this study was to evaluate the synergistic antibiofilm action of the produced and phytochemically characterized extracts of Cinnamomum verum and Brazilian green propolis (BGP) hydroethanolic extracts against multidrug-resistant clinical strains of Acinetobacter baumannii and Pseudomonas aeruginosa, in addition to their biocompatibility on human keratinocyte cell lines (HaCaT). For this, High-performance liquid chromatography analysis of the plant extracts was performed; then the minimum inhibitory and minimum bactericidal concentrations of the extracts were determined; and antibiofilm activity was evaluated with MTT assay to prevent biofilm formation and to reduce the mature biofilms. The cytotoxicity of the extracts was verified using the MTT colorimetric test, evaluating the cellular enzymatic activity. The data were analyzed with one-way ANOVA and Tukey's tests as well as Kruskal-Wallis and Dunn's tests, considering a significance level of 5%. It was possible to identify the cinnamic aldehyde in C. verum and p-coumaric, caffeic, and caffeoylquinic acids as well as flavonoids such as kaempferol and kaempferide and Artepillin-C in BGP. The combined extracts were effective in preventing biofilm formation and reducing the mature biofilms of A. baumannii and P. aeruginosa. Moreover, both extracts were biocompatible in different concentrations. Therefore, C. verum and BGP hydroethanolic extracts have bactericidal and antibiofilm action against multidrug resistant strains of A. baumannii and P. aeruginosa. In addition, the combined extracts were capable of expressively inhibiting the formation of A. baumannii and P. aeruginosa biofilms (prophylactic effect) acting similarly to 0.12% chlorhexidine gluconate.

Evaluating Antimicrobial Effectiveness of Gold Nanoparticles against Streptococcus oralis

Biofilm includes many microorganisms that causes the periodontal diseases. The increased drugs resistance against the infectious diseases is a major issue owing to excessive using of a broad spectrum of antibiotics. Recently, metallic nanoparticles (NPs) are being administered to control the growth of different types of microorganisms. For instance, gold nanoparticles (Au NPs) are found to be successful to control and limit the bacterial pathogenicity in the oral cavity without any cytotoxic effects on the human body. Aim. In this paper, it was aimed to detect the antibacterial effect of Au NPs and compare with chlorhexidine (CHX) against Streptococcus oralis (S. oralis) in dental plaque of patients with chronic periodontitis. Materials and Methods. First, supragingival and subgingival plaque samples were collected from the patients suffering from periodontal disease and incubated under aerobic or/and anaerobic conditions. Second, the morphological examination, and biochemical test by Vitec 2 machine are used to confirm the S. oralis species. Third, the synthesis of Au NPs was carried out by seed growth method and their properties were characterized. Finally, the antimicrobial effect of the Au NPs against S. oralis was evaluated by Agar well diffusion method for different Au NPs concentrations (100, 50, 25, 12.5, 6.25, 3.125, 1.562, 0.781, 0.391, 0.195, and 0.097 ppm). CHX was used as the positive control and distilled water as the negative control. The antibacterial activity data were statistically analyzed by least significant difference (LSD) using the Statistical Program for Social Science (SPSS) version 22. Results. The Au NPs with an average particles size of 43 nm, polycrystalline face-centered cubic structure were characterized. The Au NPs at 100 ppm concentration had similar antibacterial effect of CHX for inhibiting the growth of S. oralis, with no significant difference. Conclusions. The Au NPs as an antibacterial agent could be equally effective against S. oralis similar to the CHX when used at higher concentration.