Evidence-based strategy for dental biofilms: Current evidence of mouthwashes on dental biofilm and gingivitis

Antibiofilm potential of plant extracts: inhibiting oral microorganisms and Streptococcus mutans

Introduction

A range of disinfectant mouthwashes are available for oral hygiene. The gold standard is Chlorhexidine digluconate (CHX), which, like other available products, cannot be used without side effects in the long term. However, in recent years, therapy with herbal products, often considered antiquated, has regained considerable interest. Therefore, the search for plant compounds as an alternative to existing oral disinfectants is meaningful.

Methods

In this study, eleven Mediterranean plant extracts were tested for their antimicrobial effect in vitro. Methanol extracts of the following plants were produced by the pharmaceutical faculty of the University of Athens: Mentha aquatica, Mentha longifolia, Sideritis euboea, Sideritis syriaca, Stachys spinosa, Satureja parnassica, Satureja thymbra, Lavandula stoechas, Achillea taygetea, Phlomis cretica, and Vaccinium myrtillus. The extracts were dissolved for microdilution experiments at concentrations ranging from 10 to 0.019 mg/ml. The oral pathogens tested were Streptococcus mutans, Streptococcus oralis, Streptococcus sobrinus, Prevotella intermedia, Fusobacterium nucleatum, Parvimonas micra, Porphyromonas gingivalis, and Candida albicans. Enterococcus faecalis, Staphylococcus aureus, and Escherichia coli were used as references.

Results

All extracts, except the methanol extract of V. myrtillus, showed an antibacterial effect at concentrations ranging from 10 to 0.15 mg/ml. None of the extracts exhibited a significant antifungal effect. In general, the anaerobic pathogens could be inhibited and killed at lower concentrations compared to the aerobic pathogens. S. oralis also showed good susceptibility to the extracts. Additionally, the extracts' ability to inhibit biofilm formation by S. mutans was tested. L. stoechas at a concentration of 0.3 mg/ml showed a moderate inhibitory effect. The extracts of L. stoechas, S. thymbra, S. parnassica, and the methanol extract of V. myrtillus were effective at concentrations up to 1.25 mg/ml. P. cretica was able to inhibit and kill S. mutans at a concentration of 0.6 mg/ml, but its effectiveness in biofilm inhibition significantly decreased at 2.5 mg/ml.

Discussion

The study's hypothesis that all extracts would exhibit an antimicrobial effect was thus confirmed.

Insights Into the Mechanism of Action of Chlorhexidine on Porphyromonas gingivalis

Chlorhexidine (CHX) remains the most effective antiseptic in periodontal therapy, multiple reports have identified ultrastructural antibacterial effects of CHX on oral bacteria, however, little is known about its molecular mechanism of action on Porphyromonas gingivalis, an important pathobiont directly associated with the pathogenesis of periodontitis. A standardized suspension of P. gingivalis ATCC 33277 was expose to 0.20% CHX for 1 min, then counting colony forming units (CFUs) were recovered to determine the percentage of microbial inhibition. Protein extract integrity of the bacterial cells exposed to CHX was evaluated on a one-dimension sodium dodecyl sulfate polyacrylamide gel electrophoresis (1D SDS-PAGE) gel. The identification of the proteins expressed by P. gingivalis after its exposure to CHX was carried out by mass spectrometry (LC-MS). Exposure of P. gingivalis for 1 min to 0.20% CHX resulted in a 93% reduction in bacterial viability, in addition to an increase of 2.9-fold in protein expression, with the Lys gingipain protein showing the greatest increase. Exposure to 0.20% CHX 1 min on P. gingivalis resulted in 93% reduction in bacterial viability, in addition to inducing changes in the bacterial proteome, with an increased expression of gingipains, the main virulence factor of P. gingivalis.

Adsorption of oral antibacterial agents on zirconia surfaces with different crystal systems

Zirconia ceramics are widely used as dental prosthetics owing to their high biocompatibility, excellent mechanical strength, and aesthetic properties similar to color tones of natural teeth. However, there exists a growing demand for the facile attachment of antibacterial properties in long-term dental restoration. Thus, in this study, we evaluated the adsorption ability of cetylpyridinium chloride (CPC) and benzalkonium chloride (BKC)-quaternary amines widely used as antibacterial substances in commercial toothpaste and other oral care products-onto zirconia surfaces with tetragonal and monoclinic crystal structures. Although tetragonal zirconia has been widely used in dental prosthetic materials such as crowns etc., monoclinic zirconia has also been used under oral conditions because of long-term implantation. When antibacterial molecule loading on zirconia powders under simulated oral conditions, it was revealed that monoclinic zirconia adsorbed approximately five times more CPC and BKC per unit area compared with that of tetragonal zirconia. Moreover, in tetragonal zirconia, the adsorption amounts of both CPC and BKC increased slightly with growing Y2O3 content as a stabilizer. This phenomenon was attributable to the formation of complexes between rare earth elements (REE) such as Y2O3 in zirconia and quaternary amines such as CPC and BKC. In this study, the antibacterial molecular adsorption ability of dental zirconia was observed, and new advantages of zirconia in dental applications were discovered.

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.

Effect of barium silicate on mechanical properties, transmittance, and protein adsorption of resin for additive manufacturing containing zwitterionic polymer

STATEMENT OF PROBLEM

Studies on the effect of barium silicate on the material properties of additively manufactured (AM) resins containing 2-methacryloyloxyethyl phosphorylcholine (MPC) for dental applications are lacking.

PURPOSE

The purpose of this in vitro study was to evaluate the mechanical properties, transmittance, and protein adsorption of MPC-containing AM resin incorporated with different barium silicate contents and to compare these findings with those of a commercially available unfilled AM resin marketed for definitive restorations.

MATERIAL AND METHODS

Resins incorporating 6 wt% MPC and 4 different concentrations of barium silicate (10 wt%, MB10; 20 wt%, MB20; 30 wt%, MB30; and 40 wt%, MB40) were prepared. An MPC-containing resin with no filler was also prepared (0 wt%, MBN). Surface roughness (n=15), Vickers hardness (n=15), flexural strength and modulus (n=15), fracture toughness (n=15), transmittance (n=15), and protein adsorption (n=3) of the filled resin specimens were measured and compared with those of commercially available unfilled resin specimens. All data were analyzed using the Kruskal-Wallis and Dunn tests (α=.05).

RESULTS

All experimental resins had higher surface roughness than the unfilled resin (P≤.048). MB40 had higher hardness, flexural strength, flexural modulus, and fracture toughness than most other groups (P≤.047). MB10 had higher transmittance than most other groups (P≤.012). All experimental resins had lower protein adsorption than the unfilled resin, regardless of the barium silicate content (P≤.023).

CONCLUSIONS

The experimental resin containing 6 wt% MPC and 40 wt% barium silicate showed better mechanical properties and lower protein adsorption than the resin with no MPC or ceramic fillers. Transmittance decreased with the increase of barium silicate in the resins.

Caries preventing efficacy of new Isomalt-containing mouthrinse formulations: a microbial study

OBJECTIVES

The effectiveness of an Isomalt-containing mouthrinse to prevent caries development was investigated.

METHODS

Human enamel blocks were randomly assigned to five groups (n = 30/group): De-ionized distilled water (DDW), and mouthrinse containing either (IFC) 1% Isomalt, 225 ppm fluoride, and 0.05% cetylpyridinium chloride (CPC), (IF) 1% Isomalt and 225ppm fluoride, (FC) 225 ppm fluoride and 0.05% CPC or (F) 225 ppm fluoride. During 7-day demineralization in a Microbial Caries Model, mouthrinses were applied once daily for 1 min. Demineralization was assessed using Surface Microhardness testing for percentage change in SMH (%ΔSMH) and Transverse Microradiography for mineral loss (ΔZ). Data analysis (α = 0.05) used paired t-test (Intra-group comparison using SMH) and ANOVA/Tukey's for inter-group comparisons (%ΔSMH and ΔZ).

RESULTS

With SMH, relative to sound enamel baseline, demineralization was significant (P < 0.001) in all groups, except in IFC. Intergroup comparison with %ΔSMH showed significantly (p < 0.001) greater demineralization in DDW compared to other groups, and in IF, FC, and F compared to IFC (P < 0.001). With ΔZ, relative to DDW, all groups significantly (p < 0.0001) inhibited demineralization at varying percentages.

CONCLUSIONS

Mouthrinse containing Isomalt, fluoride, and CPC inhibited demineralization amidst cariogenic biofilm; thus, highlighting its potential as a more effective caries control tool than mouthrinse with only fluoride.

Effect of use of antiseptics and fluorides during orthodontic treatment on working properties of NiTi archwires in levelling dental arches : A randomized controlled trial

PURPOSE

The goal was to investigate whether the application of antiseptics and fluorides during orthodontic treatment affects the biomechanics of the levelling of dental arches by changing the working properties of nickel-titanium (NiTi) archwires.

METHODS

The sample consisted of 60 individuals aged 12-22 years (53% females). There were 20 individuals in each experimental group: (I) individuals conducted regular oral hygiene, (II) individuals used a high concentration of fluorides for intensive prophylaxis for the first month; and (III) individuals used chlorhexidine in the same manner. NiTi alloy archwires (dimensions 0.508 × 0.508 mm) were analyzed 3 months after intraoral exposure and compared to as-received NiTi wires. Elastic modulus, yield strength, springback ratio, and modulus of resilience were calculated. Dimensions of the dental arches were analyzed when NiTi alloy (T1) was placed intraorally and after 3 months (T2). Change was quantified as the difference in dimensions (T2-T1). Anterior width-to-length ratio was used as a measure for dental arch shape.

RESULTS

Intraoral exposure reduced elastic modulus, yield strength, springback ratio, modulus of resilience, loading, and unloading forces of NiTi wires (p ≤ 0.021). Chlorhexidine mouthwash and gel with high concentration of fluorides did not change these properties more than saliva with regular hygiene. The amount of change of dental arch shape in the maxilla and mandible did not differ significantly between the experimental groups.

CONCLUSION

Using antiseptics or a high concentration of fluorides during orthodontic treatment does not significantly affect the mechanical properties of NiTi wires and would not have clinical implications in changing orthodontic biomechanics.

Recent updates and feasibility of nanodrugs in the prevention and eradication of dental biofilm and its associated pathogens-A review

OBJECTIVES

Dental biofilm is one of the most prevalent diseases in humans, which is mediated by multiple microorganisms. Globally, half of the human population suffers from dental biofilm and its associated diseases. In recent trends, nano-formulated drugs are highly attractive in the treatment of dental biofilms. However, the impact of different types of nanodrugs on the dental biofilm and its associated pathogens have not been published till date. Thus, this review focuses on the recent updates, feasibility, mechanisms, limitations, and regulations of nanodrugs applications in the prevention and eradication of dental biofilm.

STUDY SELECTION, DATA AND SOURCES

A systematic search was conducted in PubMed/Google Scholar/Scopus over the past five years covering the major keywords "nanodrugs, metallic nanoparticles, metal oxide nanoparticles, natural polymers, synthetic polymers, biomaterials, dental biofilm, antibiofilm mechanism, dental pathogens", are reviewed in this study. Nearly, 100 scientific articles are selected in this relevant topic published between 2019 and 2023. Data from the selected studies dealing with nanodrugs used for biofilm treatment was qualitatively analyzed.

CONCLUSIONS

The nanodrugs such as silver nanoparticles, gold nanoparticles, selenium nanoparticles, zinc oxide nanoparticles, copper oxide nanoparticles, titanium oxide nanoparticles, hydroxyapatite nanoparticles and these inorganic nanoparticles incorporated polymer-based nanocomposites, organic/inorganic nanoparticles mediated antimicrobial photodynamic therapy exhibits an excellent antibacterial and antibiofilm activity towards dental pathogens. Finally, this review highlights that bioinspired nanodrugs will be very useful to control the dental biofilm and its associated diseases.

CLINICAL SIGNIFICANCE

Microbial influence on the oral environment is unavoidable; therefore, curing such dental biofilms and pathogens is essential for the impactful reflection of applying biocompatible treatments. In this direction, the current review explains the demand for the nanodrug in inhibiting biofilms for the effective exploration of employing treatments.

Biological Activities of Virgin Coconut and Virgin Olive Oil Mixture against Oral Primary Colonizers: An In Vitro Study

AIM AND BACKGROUND

This study aimed to explore the potential synergistic interaction of virgin coconut oil (VCO) and virgin olive oil (VOO) mixture against Streptococcus sanguinis, Streptococcus mutans, and Lactobacillus casei in a single and mixture species through the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), antiadherence, and antibiofilm activities.

MATERIALS AND METHODS

The broth microdilution technique was used to individually determine the MIC of both oils and an oil mixture (in the ratio of 1:1) in a 96-well microtiter plate. As for the MBC, the subcultured method was used. The fractional inhibitory concentration index (ΣFIC) was determined to identify the interaction types between both oils. The oil mixture at its MIC was then tested on its antibiofilm and antiadherence effect.

RESULTS

The MIC of the oil mixture against the tested microbiota was 50-100%. The oil mixture was bactericidal at 100% concentration for all the mentioned microbes except S. mutans. The ΣFIC value was 2 to 4, indicating that the VCO and VOO acted additively against the microbiota. Meanwhile, the oil mixture at MIC (50% for S. sanguinis and L. casei; 100% for S. mutans and mixture species) exhibited antiadherence and antibiofilm activity toward the microbiota in mixture species.

CONCLUSION

The oil mixture possesses antibacterial, antibiofilm, and antiadherence properties toward the tested microbiota, mainly at 50-100% concentration of oil mixture. There was no synergistic interaction found between VCO and VOO.

CLINICAL SIGNIFICANCE

Children and individuals with special care may benefit from using the oil mixture, primarily to regulate the biofilm formation and colonization of the bacteria. Furthermore, the oil mixture is natural and nontoxic compared to chemical-based oral healthcare products. How to cite this article: Ng YM, Sockalingam SNMP, Shafiei Z, et al. Biological Activities of Virgin Coconut and Virgin Olive Oil Mixture against Oral Primary Colonizers: An In Vitro Study. J Contemp Dent Pract 2024;25(3):260-266.

Antibacterial and clinical effectiveness of a mouthwash with a novel active system of amine + zinc lactate + fluoride: a randomized controlled trial

OBJECTIVES

To support the daily oral hygiene of patients experiencing gum inflammation, a new mouthwash was developed containing an amine + zinc lactate + fluoride system. In vitro and clinical efficacy was assessed using traditional methods as well as using novel site-specific and subject-specific analyses of the clinical data.

MATERIALS AND METHODS

This mouthwash was evaluated in a 12-h biofilm regrowth assay against a negative control mouthwash and in a 6-month plaque and gingivitis clinical study as compared to a negative control mouthwash. Analyses of healthy versus inflamed sites, visible plaque versus non-visible plaque sites, as well as subject-level evaluations bring new perspectives to the overall performance of this mouthwash and its significance from a patient outcome perspective.

RESULTS

Studies demonstrated that this new mouthwash provided long-term (12-h) antibacterial activity after single application in vitro and reduced clinically all plaque and gingivitis parameters after 3 months and 6 months of use when compared to the negative control mouthwash. Examination of site-level and subject-level data determined that this mouthwash significantly increased the number of healthy sites in the oral cavity and significantly improved the gum health of subjects in the study, as compared to the negative control mouthwash.

CONCLUSIONS

In vitro and clinical research has demonstrated the antibacterial and clinical benefits of this mouthwash containing an amine compound + zinc lactate + fluoride system.

CLINICAL RELEVANCE

Our subject-specific and site-specific analyses provide the dental practitioner with tools that can be used to guide patients who suffer from gingivitis toward optimal product selection and use.

CLINICAL TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov (reference no. NCT05821712).

Effect of Commercial Mouth Rinses on Physical Properties of Conventional and Bulk-fill Resin Composites

OBJECTIVE

To evaluate the effects of commercial mouth rinses on color, roughness, sorption (SR), and solubility (SL) of resin composites.

METHODS AND MATERIALS

Disc-shaped specimens (stage I: 6 mm × 2 mm; stage II: 10 mm × 1.5 mm) were made from the following resin composites (n=10): conventional nanofilled (Filtek Z350XT, 3M Oral Care), conventional nanohybrid (Luna, SDI), bulk-fill nanofilled (Filtek One Bulk-Fill, 3M Oral Care), and bulk-fill nanohybrid (Aura Bulk-Fill, SDI) exposed to distilled water (control), blue mouth rinse without alcohol (Colgate Total 12 Clean Mint, Colgate-Palmolive), or blue mouth rinse with alcohol and essential oil (Listerine Tartar Control, Johnson & Johnson). In stage I, tests were performed at the baseline, and after the immersion in solution time points to evaluate coordinates of the CIEL*a*b* system (ΔL*, Δa*, Δb*), general color change (ΔEab, ΔE00, and ΔSGU), and surface roughness (Ra). In stage II, SR and SL were evaluated (ISO 4049:2019) after immersion in the solutions for 7 days. The results were evaluated by generalized linear models (Ra, SR), Kruskal-Wallis, and Dunn tests (color, SL), with α = 0.05.

RESULTS

There were no significative differences for Ra between the solutions. Both mouth rinses promoted significantly negative ΔL* (Luna), Δa* (Filtek One Bulk-fill), and Δb* (all materials except conventional nanofilled resin composite). Mouth rinse without alcohol promoted significantly negative Δa* on all resin composites tested. Both mouth rinses promoted higher ΔEab and ΔE00 for bulk-fill resin composites compared to control. Mouth rinse with alcohol caused higher ΔSGU for bulk-fill nanofilled resin composite. It also promoted greater SR in all the resin composites compared with mouth rinse without alcohol and higher SR in nanohybrid resin composites compared with control. Both mouth rinses promoted higher SL values in Luna and differed significantly from control.

CONCLUSIONS

The physical properties were manufacturer dependent and mediated by mouth rinses. The mouth rinses promoted color changes in the resin composites, pointing out that bulk-fill resin composites were more affected by these effects, especially when the mouth rinse contained essential oil and alcohol.

Delivery of biologics: Topical administration

Biologics are unaffordable to a large majority of the global population because of prohibitively expensive fermentation systems, purification and the requirement for cold chain for storage and transportation. Limitations of current production and delivery systems of biologics were evident during the recent pandemic when <2.5% of vaccines produced were available to low-income countries and ∼19 million doses were discarded in Africa due to lack of cold-chain infrastructure. Among FDA-approved biologics since 2015, >90% are delivered using invasive methods. While oral or topical drugs are highly preferred by patients because of their affordability and convenience, only two oral drugs have been approved by FDA since 2015. A newly launched oral biologic costs only ∼3% of the average cost of injectable biologics because of the simplified regulatory approval process by elimination of prohibitively expensive fermentation, purification, cold storage/transportation. In addition, the cost of developing a new biologic injectable product (∼$2.5 billion) has been dramatically reduced through oral or topical delivery. Topical delivery has the unique advantage of targeted delivery of high concentration protein drugs, without getting diluted in circulating blood. However, only very few topical drugs have been approved by the FDA. Therefore, this review highlights recent advances in oral or topical delivery of proteins at early or advanced stages of human clinical trials using chewing gums, patches or sprays, or nucleic acid drugs directly, or in combination with, nanoparticles and offers future directions.

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.

Anti-biofilm activity of a novel nanoemulsion containing Curcuma xanthorrhiza oil

OBJECTIVES

We aimed to solubilize Curcuma xanthorrhiza oil (CXO) using nanoemulsification and evaluate its inhibitory effects against biofilm formation.

METHODS

The components of CXO were evaluated through high-performance liquid chromatography (HPLC) analysis. Healthy human saliva was inoculated onto hydroxyapatite discs to form microcosm biofilms for four days and treated six times with each antimicrobial agent: distilled water (DW), CXO emulsion (EM), CXO nanoemulsion (NE), and positive controls (Listerine and chlorhexidine). Biofilm fluorescence imaging was performed using quantitative light-induced fluorescence, and cell viability and dry-weight measurements were obtained. We compared the bacterial cell and extracellular polysaccharide (EPS) biovolume and thickness using confocal laser scanning microscopy (CLSM).

RESULTS

HPLC analysis revealed that CXO was composed of approximately 47% xanthorrhizol. Compared with DW, NE exhibited significantly lower red fluorescence intensity and area (42% and 37%, p < 0.001 and p < 0.001, respectively), and reduced total and aciduric bacterial cell viability (7.3% and 3.9%, p < 0.001, p = 0.01, respectively). Furthermore, the bacterial cell and EPS biovolume and thickness in NE decreased by 40-80% compared to DW, similar to chlorhexidine. Conversely, EM showed a significant difference only in cell viability against total bacteria when compared with DW (p = 0.003), with EPS biovolume and thickness exhibiting higher values than DW.

CONCLUSIONS

Nanoemulsification successfully solubilized CXO and demonstrated superior anti-biofilm effects compared to the emulsion form.

CLINICAL SIGNIFICANCE

These findings suggest the potential use of NE as a novel antimicrobial agent for preventing oral diseases.

Effects of hypochlorous acid mouthwash on salivary bacteria including Staphylococcus aureus in patients with periodontal disease: a randomized controlled trial

BACKGROUND

The effects of a low concentration of hypochlorous acid (HOCl) mouthwash on salivary bacteria remained unclear. We aimed to evaluate the antibacterial effects of 100 ppm HOCl mouthwash on salivary bacteria, including Staphylococcus aureus (S. aureus), in patients with periodontal disease (PD).

METHODS

Patients with PD were randomized into mouthwash-only (MW, n = 26) and mouthwash with periodontal flosser (MWPF, n = 27) groups. Patients without PD were selected for the control group (n = 30). S. aureus culture and saliva samples (before and after the intervention) were collected for bacterial DNA extraction. A real-time polymerase chain reaction assay and serial dilutions of S. aureus culture and saliva samples were used to measure the salivary bacteria total count (SBTC) and confirm the antibacterial effects of the mouthwash using S. aureus.

RESULTS

No significant difference in demographic data was observed among the three groups. Before the intervention, the baseline SBTC of the MW and MWPF groups was significantly higher than that of the control group. After the mouthwash rinses, the SBTC data significantly changed in the MW and MWPF groups only (by 62.4% and 77.4%, respectively). After the base-2 log-transformation of the SBTC data, a similar trend was observed. Linear regression revealed that baseline SBTC and the MWPF intervention significantly affected SBTC reduction percentage by volume. After incubation with 10% (v/v) of mouthwash, the survival rates of 106 and 107 colony-forming units/mL of S. aureus were 0.51% ± 0.06% and 1.42% ± 0.37%, respectively.

CONCLUSIONS

These study results indicated that 100 ppm HOCl mouthwash treatment could effectively reduce SBTC in patients with PD and the abundance of S. aureus. It provides that the HOCl mouthwash can be an option for individuals to help control SBTC, especially in patients with PD.

TRIAL REGISTRATION

The study protocol was approved by the Institutional Review Board of Kaohsiung Medical University Hospital (KMUHIRB-F(I)-20200042) on 20/03/2020 and retrospectively registered at ClinicalTrial.gov (NCT05372835) on 13/05/2022.

Short-term anti-plaque effect of a cymenol mouthwash analysed using the DenTiUS Deep Plaque software: a randomised clinical trial

BACKGROUND

The effect of cymenol mouthwashes on levels of dental plaque has not been evaluated thus far.

OBJECTIVE

To analyse the short-term, in situ, anti-plaque effect of a 0.1% cymenol mouthwash using the DenTiUS Deep Plaque software.

METHODS

Fifty orally healthy participants were distributed randomly into two groups: 24 received a cymenol mouthwash for eight days (test group A) and 26 a placebo mouthwash for four days and a cymenol mouthwash for a further four days thereafter (test group B). They were instructed not to perform other oral hygiene measures. On days 0, 4, and 8 of the experiment, a rinsing protocol for staining the dental plaque with sodium fluorescein was performed. Three intraoral photographs were taken per subject under ultraviolet light. The 504 images were analysed using the DenTiUS Deep Plaque software, and visible and total plaque indices were calculated (ClinicalTrials ID NCT05521230).

RESULTS

On day 4, the percentage area of visible plaque was significantly lower in test group A than in test group B (absolute = 35.31 ± 14.93% vs. 46.57 ± 18.92%, p = 0.023; relative = 29.80 ± 13.97% vs. 40.53 ± 18.48%, p = 0.024). In comparison with the placebo, the cymenol mouthwash was found to have reduced the growth rate of the area of visible plaque in the first four days by 26% (absolute) to 28% (relative). On day 8, the percentage areas of both the visible and total plaque were significantly lower in test group A than in test group B (visible absolute = 44.79 ± 15.77% vs. 65.12 ± 16.37%, p < 0.001; visible relative = 39.27 ± 14.33% vs. 59.24 ± 16.90%, p < 0.001; total = 65.17 ± 9.73% vs. 74.52 ± 13.55%, p = 0.007). Accounting for the growth rate with the placebo mouthwash on day 4, the above results imply that the cymenol mouthwash in the last four days of the trial reduced the growth rate of the area of visible plaque (absolute and relative) by 53% (test group A) and 29% (test group B), and of the area of total plaque by 48% (test group A) and 41% (test group B).

CONCLUSIONS

The 0.1% cymenol mouthwash has a short-term anti-plaque effect in situ, strongly conditioning the rate of plaque growth, even in clinical situations with high levels of dental plaque accumulation.

Antibacterial, anti-inflammatory and wet-adhesive poly(ionic liquid)-based oral patch for the treatment of oral ulcers with bacterial infection

Oral aphthous ulcers are a common inflammatory efflorescence of oral mucosa, presenting as inflammation and oral mucosal damage and manifesting as pain. The moist and highly dynamic environment of the oral cavity makes the local treatment of oral aphthous ulcers challenging. Herein, a poly(ionic liquid)-based diclofenac sodium (DS)-loaded (PIL-DS) buccal tissue adhesive patch fabricated with intrinsically antimicrobial, highly wet environment adhesive properties and anti-inflammatory activities to treat oral aphthous ulcers was developed. The PIL-DS patch was prepared via polymerization of a catechol-containing ionic liquid, acrylic acid, and butyl acrylate, followed by anion exchange with DS-. The PIL-DS can adhere to wet tissues, including mucosa muscles and organs, and efficiently deliver the carried DS- at wound sites, exerting remarkable synergistic antimicrobial (bacteria and fungi) properties. Accordingly, the PIL-DS elicited dual therapeutic effects on oral aphthous ulcers with Staphylococcus aureus infection through antibacterial and anti-inflammatory activities, significantly accelerating oral aphthous ulcer healing as an oral mucosa patch. The results indicated that the PIL-DS patch, with inherently antimicrobial and wet adhesion properties, is promising for treating oral aphthous ulcers in clinical practice. STATEMENT OF SIGNIFICANCE: Oral aphthous ulcers are a common oral mucosal disease, which could lead to bacterial infection and inflammation in severe cases, especially for people with large ulcers or low immunity. However, moist oral mucosa and highly dynamic oral environment make it challenging to maintain therapeutic agents and physical barriers at the wound surface. Therefore, an innovative drug carrier with wet adhesion is urgently needed. Herein, a poly(ionic liquid)-based diclofenac sodium (DS)-loaded (PIL-DS) buccal tissue adhesive patch was developed to treat oral aphthous ulcers showing intrinsically antimicrobial and highly wet environment adhesive properties due to the presence of catechol-containing ionic liquid monomer. Additionally, the PIL-DS showed significantly therapeutic effects on oral aphthous ulcers with S. aureus infection through antibacterial and anti-inflammatory activities. We expect that our work can provide inspiration for the development of treatment for microbially infected oral ulcers.

Multicationic Quaternary Ammonium Compounds: A Framework for Combating Bacterial Resistance

During previous stages of research, high biocidal activity toward microorganism archival strains has been used as the main indicator in the development of new antiseptic formulations. Although this factor remains one of the most important characteristics of biocide efficiency, the scale of antimicrobial resistance spread causes serious concern. Therefore, focus shifts toward the development of formulations with a stable effect even in the case of prolonged contact with pathogens. Here, we introduce an original isocyanuric acid alkylation method with the use of available alkyl dichlorides, which opened access to a wide panel of multi-QACs with alkyl chains of various lengths between the nitrogen atoms of triazine and pyridine cycles. We used a complex approach for the resulting series of 17 compounds, including their antibiofilm properties, bacterial tolerance development, and antimicrobial activity toward multiresistant pathogenic strains. As a result of these efforts, available compounds have shown higher levels of antibacterial activity against ESKAPE pathogens than widely used commercial QACs. Hit compounds possessed high activity toward clinical bacterial strains and have also demonstrated a long-term biocidal effect without significant development of microorganism tolerance. The overall results indicated a high level of antibacterial activity and the broad application prospects of multi-QACs based on isocyanuric acid against multiresistant bacterial strains.

3,3'-Diindolylmethane (DIM): A Potential Therapeutic Agent against Cariogenic Streptococcus mutans Biofilm

Indole, a metabolite of the amino acid tryptophan, has been proven to act as a signal molecule in bacteria, acting in different aspects of biofilm formation. The oral biofilm is a type of biofilm that has consequences for human health. It is a complex, three-dimensional structure that develops on the surface of teeth via the attachment of primary microbial colonizers. Many oral infections are caused by an imbalance occurring in the microorganisms naturally found in oral biofilms and are considered major public health concerns. In this study, we test the effect of a natural bis-indole, 3,3'-Diindolylmethane (DIM), in mitigating the pathogenicity of the oral biofilm inhabiting bacterium Streptococcus mutans, a bacterium that is considered to be a principal etiological agent in dental caries. Our study found that DIM was able to attenuate S. mutans biofilm formation by 92%. Additionally, treatment with DIM lowered extracellular polymeric substance (EPS) production and decreased its durability significantly under acidic conditions. Therefore, the anti-biofilm and anti-virulence properties of DIM against S. mutans bacteria in an "oral setting" provides evidence for its usefulness in reducing biofilm formation and potentially for caries attenuation.

Antimicrobial Efficiency of Pistacia lentiscus L. Derivates against Oral Biofilm-Associated Diseases-A Narrative Review

Pistacia lentiscus L. (PlL) has been used for centuries in traditional medicine. The richness in antimicrobial biomolecules of Pll derivates can represent an alternative to chemically formulated agents used against oral infections. This review summarizes the knowledge on the antimicrobial activity of PlL essential oil (EO), extracts, and mastic resin against microorganisms being of relevance in oral biofilm-associated diseases. Results demonstrated that the potential of PlL polyphenol extracts has led to increasing scientific interest. In fact, the extracts are a significantly more effective agent than the other PlL derivates. The positive findings regarding the inhibition of periodontal pathogens and C. albicans, together with the antioxidant activity and the reduction of the inflammatory responses, suggest the use of the extracts in the prevention and/or reversal of intraoral dysbiosis. Toothpaste, mouthwashes, and local delivery devices could be effective in the clinical management of these oral diseases.

Lippia origanoides derivatives in vitro evaluation on polymicrobial biofilms: Streptococcus mutans, Lactobacillus rhamnosus and Candida albicans

OBJECTIVE

This work evaluated the Lippia origanoides derivatives in vitro effect on polymicrobial biofilms of Streptococcus mutans, Lactobacillus rhamnosus and Candida albicans. Additionally, the cytotoxic effect of the oils on human skin keratinocytes (HaCaT) and fibroblasts of the periodontal ligament (FLP) cell lines was evaluated.

DESIGN

The minimum inhibitory concentration, the inhibitory activity on monomicrobial (S. mutans) and polymicrobial biofilm (S. mutans, L. rhamnosus and C. albicans) of L. origanoides four essential oils and terpenes (thymol and carvacrol) were evaluated. The cytotoxic effect of each one of the compounds was measured, and all the tests were compared against chlorhexidine.

RESULTS

All the evaluated compounds reached an inhibition percentage of S. mutans monomicrobial biofilms formation of 100 % at 600 µg/mL (p < 0.0001). The highest concentration (2 MIC) eradicated 100 % of S. mutans-preformed biofilms after 5 min L. origanoides carvacrol + thymol and thymol chemotypes showed marked reductions in topography, the number of microbial cells and extracellular matrix on polymicrobial biofilm. The cytotoxic effect of the compounds was very similar to chlorhexidine.

CONCLUSIONS

L. origanoides essential oils have an inhibitory effect on mono and polymicrobial biofilms. The oils present a similar cytotoxic effect to chlorhexidine on HaCaT and FLP cell lines. However, including these compounds in formulations for clinical use is an exciting proposal yet to be investigated.

From Antibacterial to Antibiofilm Targeting: An Emerging Paradigm Shift in the Development of Quaternary Ammonium Compounds (QACs)

In a previous development stage, mostly individual antibacterial activity was a target in the optimization of biologically active compounds and antiseptic agents. Although this targeting is still valuable, a new trend has appeared since the discovery of superhigh resistance of bacterial cells upon their aggregation into groups. Indeed, it is now well established that the great majority of pathogenic germs are found in the environment as surface-associated microbial communities called biofilms. The protective properties of biofilms and microbial resistance, even to high concentrations of biocides, cause many chronic infections in medical settings and lead to serious economic losses in various areas. A paradigm shift from individual bacterial targeting to also affecting more complex cellular frameworks is taking place and involves multiple strategies for combating biofilms with compounds that are effective at different stages of microbiome formation. Quaternary ammonium compounds (QACs) play a key role in many of these treatments and prophylactic techniques on the basis of both the use of individual antibacterial agents and combination technologies. In this review, we summarize the literature data on the effectiveness of using commercially available and newly synthesized QACs, as well as synergistic treatment techniques based on them. As an important focus, techniques for developing and applying antimicrobial coatings that prevent the formation of biofilms on various surfaces over time are discussed. The information analyzed in this review will be useful to researchers and engineers working in many fields, including the development of a new generation of applied materials; understanding biofilm surface growth; and conducting research in medical, pharmaceutical, and materials sciences. Although regular studies of antibacterial activity are still widely conducted, a promising new trend is also to evaluate antibiofilm activity in a comprehensive study in order to meet the current requirements for the development of highly needed practical applications.

A novel microfluidic compact disc to investigate electrochemical property changes between artificial and real salivary samples mixed with mouthwashes using electrical impedance analysis

Diagnosing oral diseases at an early stage may lead to better preventive treatments, thus reducing treatment burden and costs. This paper introduces a systematic design of a microfluidic compact disc (CD) consisting of six unique chambers that run simultaneously from sample loading, holding, mixing and analysis. In this study, the electrochemical property changes between real saliva and artificial saliva mixed with three different types of mouthwashes (i.e. chlorhexidine-, fluoride- and essential oil (Listerine)-based mouthwashes) were investigated using electrical impedance analysis. Given the diversity and complexity of patient's salivary samples, we investigated the electrochemical impedance property of healthy real saliva mixed with different types of mouthwashes to understand the different electrochemical property which could be a foundation for diagnosis and monitoring of oral diseases. On the other hand, electrochemical impedance property of artificial saliva, a commonly used moisturizing agent and lubricant for the treatment of xerostomia or dry mouth syndrome was also studied. The findings indicate that artificial saliva and fluoride-based mouthwash showed higher conductance values compared to real saliva and two other different types of mouthwashes. The ability of our new microfluidic CD platform to perform multiplex processes and detection of electrochemical property of different types of saliva and mouthwashes is a fundamental concept for future research on salivary theranostics using point-of-care microfluidic CD platform.

Use and efficacy of mouthwashes in elderly patients: A systematic review of randomized clinical trials

INTRODUCTION

A higher prevalence of oral problems has been observed in the elderly population. One of the treatment options for some of these pathologies is the administration of mouthwashes combined with mechanical removal techniques. Besides, each type of oral rinse treats certain oral diseases, and it should be selected for each specific situation.

OBJECTIVE

To determine the use and efficacy of mouthwashes in the elderly as a treatment for various pathologies, to indicate the most common kinds of mouth-rinses used, the diseases treated with them, their efficacy in each treatment, and their effectiveness when they are combined with other treatments.

MATERIAL AND METHODS

The review has been carried out following the PRISMA 2020 Statement. Individualized bibliographic searches were performed in five databases. Randomized clinical trials are included in patients over 60 years old where mouthwashes were administered to treat or prevent specific diseases. The PICO question aimed to assess what type of mouthwashes elderly patients use, what they use them for, and their efficacy. Study selection, data extraction, and quality analysis were achieved using the RoB-2 guide.

RESULTS

Thirteen articles were chosen to perform the qualitative analysis. The bibliometric analysis was carried out. We have eleven randomized controlled clinical trials and two uncontrolled. The mouthwash more used was chlorhexidine, followed by essential oils and fluorides. The most studied pathologies were a periodontal disease, caries, candidiasis, denture stomatitis, and xerostomia. Chlorhexidine used weekly is effective as antiplaque and antigingivitis. Fluorides effectively prevent and reverse caries; nystatin and essential oils to treat candidiasis; and pilocarpine rinse to manage xerostomia.

CONCLUSIONS

The included studies show that mouthwashes are widely extended in the elderly population, and each sort is specifically designed for treating a particular condition.

Efficacy of 0.05% cetylpyridinium chloride mouthwash as an adjunct to toothbrushing compared with 0.12% chlorhexidine gluconate mouthwash in reducing dental plaque and gingival inflammation: A randomized control trial

OBJECTIVES

This study determined the efficacy of alcohol-free 0.05% cetylpyridinium chloride (CPC) mouthwash as an adjunct to twice-daily toothbrushing in comparison with 0.12% chlorhexidine gluconate (CHX) mouthwash and a placebo in reducing plaque accumulation and gingival inflammation. The side effects of the mouthwashes were also determined.

MATERIALS AND METHODS

A double-blind, parallel, randomized control trial was conducted with 219 university students who were divided into three trial groups using block randomization: CPC, CHX and placebo groups. Clinical oral examinations to assess dental plaque accumulation (modified Quigley-Hein Plaque Index), gingival health (Löe and Silness Gingival Index) and tooth staining (modified Lobene Stain Index) were performed at baseline and at 6 weeks.

RESULTS

Plaque and gingivitis scores were not significantly different among participants at baseline. After 6 weeks, plaque and gingivitis scores between the CPC and placebo groups and between the CHX and placebo groups were found to be significantly different. However, there was no significant difference between the CPC and CHX groups. The staining scores of participants in the CPC group were lower than those in the CHX group, but the difference was not significant. Taste alteration and numbness were more common among participants in the CHX group than in the CPC group. No significant difference in the perception of a burning sensation was observed.

CONCLUSIONS

The 0.05% CPC mouthwash was as efficient as 0.12% CHX mouthwash in reducing dental plaque accumulation and gingival inflammation with fewer side effects, supporting its use as an adjunct to toothbrushing.

Enhancement of chlorhexidine activity against planktonic and biofilm forms of oral streptococci by two Croton spp. essential oils from the Caatinga biome

This work investigates the ability of two Croton spp. essential oils (EO) to enhance chlorhexidine (CHX) activity against oral streptococci. EO's chemical composition of Croton argyrophyllus and C. pluriglandulosus was determined by GC-MS/FID. The microbial growth kinetics and minimum inhibitory concentration (MIC) of EOs and CHX were determined, followed by their synergism against S. mutans UA159 and ATCC 25175, S. salivarius ATCC 7073 and S. sp. ATCC 15300. The microplate-based method was used to determine the EO/CHX activity against 24-h-old biofilms. The major compounds were α-pinene (54.74%) and bicyclogermacrene (16.08%) for EOAr and 1,8-cineole (17.41%), methyleugenol (16.06%) and elemicin (15.99%) for EOPg. Both EO had MIC around 16,000 µg/mL. EOs/CHX presented a synergistic effect against most strains (FICi from 0.133 to 0.375), and OE/CHX-treated biofilms showed a reduction in biomass and cell viability compared to CHX, only (p < 0.01). Thus, the EOs works as natural adjuvants for CHX.

EO-based mouthwashes: Is there something that should be known?

The possibility to utilize the antibacterial and antibiofilm potential of essential oils (EOs) in dentistry is recognized and best seen in the design of EO-based mouthwashes. The up-to-date results, obtained with the most commonly used formulation being consisted of thymol, eucalyptol, menthol, and methyl salicylate (Listerine), proved its efficacy against plaque and gingival inflammation. However, novel alcohol-free products remain to be further investigated. Commercially available mouthwash containing curcumin, clove oil, mentha oil, eucalyptol, thymol and tea tree oil, and the mouthwash based on ginger EO (a-zingiberene, b-bisabolene, b-sesquiphellandrene, curcumene), reduced plaque index and improved periodontal status of the patients. The plaque index was also reduced and overall healing was improved after the surgical removal of the third molar by mouthwash containing John wort oil. In addition, Cinnamomum zeylanicum EO-based mouthwash and mouthwash containing peppermint oil were efficient against stomatitis and xerostomia, respectively. In addition to beneficial effects achieved in the mouth, i.e. at the appropriate site of application, novel investigations pointed-out that EO-based mouthwashes could be recognized as efficient in the reduction of bacterial and viral aerosols. This has been shown for Listerine, and for several mouthwashes containing following active substances of plants' EO origin: a-farnesene, b-farnesene, farnesol, nerolidol, a-bulnesene, eremanthin, b-sesquiphellandrene, spiroether, cinnamylacetate, cinnamaldehyde, eugenol, menthol, and carvacrol. This finding could be of special interest, in order to be included in further clinical studies related to COVID -19 pandemic.

The antibiofilm activity of selected substances used in oral health prophylaxis

Oral health is a window to a patient’s general well-being. Balance in oral microbiome functions is crucial for health maintenance. A state of oral dysbiosis may lead to a variety of local and systemic pathological conditions. The presence of dental plaque is related to the majority of oral infections. Proper oral hygiene is crucial and the most economic practice contributing to oral health prophylaxis. Aside from prophylactic treatments provided by dental practitioners, mouth rinses, containing antimicrobial agents, are one of the possible tools used for oral care. Our study was to determine whether available mouth rinses and selected products dedicated for professional use are efficient to eradicate biofilm formed by reference and clinical strains of Streptococcus mutans, Streptococcus sanguinis, Streptococcus oralis, Streptococcus mitis, Staphylococcus aureus, Enterococcus faecalis, Lactobacillus rhamnosus and Candida albicans on the surface of hydroxyapatite – major mineral component of a tooth. Therefore, such antimicrobials as chlorhexidine, cetylpyridine chloride, polyhexanide, silver nanoparticles, sulphonated phenolics, and natural antiplaque essential oils and coconut oil were analyzed. Applied experimental settings in in vitro models were designed to reflect accurately the recommended use of the tested substances, therefore four types of eradication procedure were conducted. Sialorrhea simulation was also performed to evaluate antibiofilm potential of diluted mouth rinses. Biofilm was investigated with quantitative method where absorbance values were measured. Statistical differences were assessed using the Kruskal–Wallis test with a post-hoc Dunnett’s analysis. Results have shown that biofilms displayed a diversified sensitivity to the tested antimicrobials. The highest antibiofilm activity was detected for cetylpyridine chloride while the lowest for chlorhexidine. However the differences in E. faecalis biofilm reduction observed after the use of these two compounds were not statistically significant (p > 0.05), whereas all observed differences in S. aureus survival after exposure to the examined antimicrobial agents were statistically significant (p < 0.5). The PHMB, both in standard and in sialorrhea simulated conditions had the highest potential against streptococci. The coconut oil reduced C. albicans fungus biofilm by 65.48% but low eradication level was observed in case of bacterial biofilms. The dehydrating mechanism of action of sulfonated phenolics turned out to be ineffective against streptococcal biofilm which in turn was effectively eradicated by silver nanoparticles. The implementation of Antibiofilm Dressing's Activity Measurement method allowed to observe strain-related differences in terms of antimicrobial sensitivity. The obtained results may be introduced in everyday out-patient dental plaque prophylaxis as well as clinical environment.

Antibacterial and Antibiofilm Effect of Honey in the Prevention of Dental Caries: A Recent Perspective

The successful application of honey in wound care management has been achieved due to honey’s potent antibacterial effects, characterised by its multifactorial action. Impressive clinical efficacy has ignited its further use in diverse clinical disciplines, including stomatology. Indeed, there is increasing usage of honey in dental medicine as a preventive or therapeutic remedy for some periodontal diseases mainly associated with bacteria, such as dental caries, gingivitis and mucositides. Dental caries is undoubtedly a major oral health problem worldwide, with an increasing tendency of incidence. The purpose of this perspective review is to describe the recent progress in the laboratory and clinical use of honey in the prevention of dental caries, with emphasis on the antibacterial and antibiofilm effects of honey. The role of honey in the cariogenic process is also discussed. In addition, the quality of honey and the urgent in vitro evaluation of its antibacterial/antibiofilm properties before clinical use are highlighted. Findings based on data extracted from laboratory studies demonstrate the pronounced antibacterial effect of different honeys against a number of periodontal pathogens, including Streptococcus mutans. Although the promising antibiofilm effects of honey have been reported mainly against S. mutans, these results are limited to very few studies. From a clinical point of view, honey significantly reduces dental plaque; however, it is not superior to the conventional agent. Despite the positive in vitro results, the clinical effectiveness of honey in the prevention of dental caries remains inconclusive since further robust clinical studies are needed.

Strategies to Combat Caries by Maintaining the Integrity of Biofilm and Homeostasis during the Rapid Phase of Supragingival Plaque Formation

Bacteria in the oral cavity, including commensals and opportunistic pathogens, are organized into highly specialized sessile communities, coexisting in homeostasis with the host under healthy conditions. A dysbiotic environment during biofilm evolution, however, allows opportunistic pathogens to become the dominant species at caries-affected sites at the expense of health-associated taxa. Combining tooth brushing with dentifrices or rinses combat the onset of caries by partially removes plaque, but resulting in the biofilm remaining in an immature state with undesirables’ consequences on homeostasis and oral ecosystem. This leads to the need for therapeutic pathways that focus on preserving balance in the oral microbiota and applying strategies to combat caries by maintaining biofilm integrity and homeostasis during the rapid phase of supragingival plaque formation. Adhesion, nutrition, and communication are fundamental in this phase in which the bacteria that have survived these adverse conditions rebuild and reorganize the biofilm, and are considered targets for designing preventive strategies to guide the biofilm towards a composition compatible with health. The present review summarizes the most important advances and future prospects for therapies based on the maintenance of biofilm integrity and homeostasis as a preventive measure of dysbiosis focused on these three key factors during the rapid phase of plaque formation.

Evaluation of the Effects of Mouthwash on the Morphology and Cell Viability of Osteoblast-Like Cells

This study evaluated the effects of multiple mouthwashes on the cellular viability or the morphology of preosteoblasts. Mouse calvarial osteoblast-like cells were cultured and treated with mouthwashes of (1) benzydamine hydrochloride; (2) cetylpyridinium chloride and benzalkonium chloride; (3) methyl salicylate, menthol, eucalyptol, and thymol; and (4) sodium fluoride, xylitol, and chitosan. The treatment times were 30 seconds, 90 seconds, and 270 seconds. Cell morphology was evaluated with a microscope, and the viability of the treated cells was analyzed quantitatively using a commercially available kit. The untreated control group exhibited well-stretched fibroblast-like morphology. Treatment with mouthwash resulted in morphological changes in all groups. Treatment with sodium fluoride resulted in more noticeable changes. Treatment with mouthwash for 30 seconds produced a significant decrease in cell viability. An increase in time to 90 and 270 seconds did not produce additional noticeable changes. To conclude, commercially available mouthwashes created changes in cell morphology and decreased the cell viability of osteoblast-like cells irrespective of ingredients and treatment time.

In vivo investigation of gingival health and oxidative stress changes in patients undergoing orthodontic treatment with and without fluoride use

Background and Aims:

We aimed to investigate gingival index changes and oxidative stress in orthodontic patients with and without the use of fluoridated agents over a 6-month period.

Materials and Methods:

Ninety subjects divided into three groups (30 untreated controls, 30 with fixed appliances using nonfluoridated toothpaste, and 30 with fixed appliances using fluoridated toothpastes and mouthwashes ) comprised the sample. The Loe gingival index was used to rank gingival health at four specific time periods in the groups to determine differences (before, at 7 days, 30 days, and 6 months). Gingival crevicular fluid was evaluated for cytokines (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) to determine differences in oxidative status between the groups.

Results:

Controls showed no changes in gingival index throughout the 6-month observation period. There was a deterioration in gingival health in both the fluoridated and nonfluoridated groups till 6 months. IL-1β levels in the fluoridated group increased from the 7^th day, reached a peak at 30 days, and remained slightly elevated at 6 months. The nonfluoridated group also showed elevated levels at all tested time periods, but levels were lower as compared to fluoridated samples. The differences in IL-1β values between the fluoridated and nonfluoridated treated groups were significant. TNF-α levels in the three groups also showed a similar pattern with elevated levels seen in both the treated groups at the 7^th, 30-day, and 6-month periods. The fluoridated group showed the highest levels at three time periods which was statistically significant.

Conclusions:

Gingival health of subjects treated with fixed orthodontic appliances deteriorated from appliance placement till a 6-month time period. Cytokines such as IL-1β and TNF-α associated with oxidative stress during orthodontic treatment increased in both the treated groups, with higher levels in fluoridated subjects. Long-term consequences of oxidative stress changes need further investigation.

Hydroxyapatite-Based Solution as Adjunct Treatment for Biofilm Management: An In Situ Study

Synthetic hydroxyapatite-based solution is a bioinspired material that may present anti-adhesive properties, restraining the dental biofilm formation without causing adverse effects. This in situ study aims to evaluate the effects of three different hydroxyapatite (HAP) watery solutions as a mouthwash against biofilm adhesion on different dental material surfaces under oral conditions. Hence, four volunteers carried maxillary splints containing enamel, titanium, ceramics, and polymethyl-methacrylate resin (PMMA) samples. Three HAP watery solutions (5%) were prepared with HAP particles presenting different shapes and sizes (HAP I, HAP II, HAP III). During 24 h, the volunteers rinsed two times with one of the following selected tested solution: HAP I, HAP II, HAP III, water, or chlorhexidine 0.2% (CHX). The first rinse was performed 3 min after pellicle formation; the second rinse occurred after a 12 h interval. The surface analysis was performed by scanning electron microscopy (SEM), fluorescence microscopy (FM), and transmission electron microscopy (TEM). Statistical and microscopic analysis showed that most samples treated with any HAP solution revealed reduced biofilm coverage presenting comparable results to CHX treated samples, however without altering the microorganisms' viability. In conclusion, the results of this investigation showed that a pure hydroxyapatite-based mouthrinse could be a promising bioinspired adjunct solution for biofilm management.

Antimicrobial resistance of bacterial strains in patients undergoing orthodontic treatment with and without fixed appliances

OBJECTIVES

To identify microorganisms isolated from patients wearing fixed orthodontic appliances and to evaluate the resistance of isolated bacterial strains to different antimicrobials.

MATERIALS AND METHODS

Seventeen healthy patients wearing a fixed orthodontic appliance (group 1) and six nonwearers (group 2, control group) were evaluated. The biofilm that formed around the orthodontic brackets was collected, and the samples were then plated in a chromogenic medium (chromIDT, bioMérieux). Colony-forming units (CFUs) were isolated and inoculated in blood-agar medium. Automated biochemical tests (VITEK 2, bioMérieux) were carried out to identify the genus and species of the microorganisms and the resistance provided by 43 drugs (37 antibacterial and 6 antifungal).

RESULTS

The most prevalent microbial genera identified in group 1 were Streptococcus (24.0%), Staphylococcus (20.0%), Enterobacter (12.0%), Geobacillus (12.0%), and Candida (12.0%), and the most frequent species were Enterobacter cloacae complex (13.6%) and Staphylococcus hominis (13.6%). In group 2, the most prevalent genera were Streptococcus (57.1%), Staphylococcus (14.2%), Sphingomonas (14.2%), and Enterobacter (14.2%). With regard to antimicrobial resistance, 14 of 19 (74%) isolated bacterial strains were found to be resistant to at least 1 of the tested antimicrobials.

CONCLUSIONS

The findings of the present study suggest that patients undergoing orthodontic treatment with fixed appliances have a more complex biofilm with a higher level of bacterial resistance.

Does Customized Handle Toothbrush Influence Dental Plaque Removal in Children with Down Syndrome? A Randomized Controlled Trial

The present study aimed to evaluate the effectiveness of customized handle toothbrush in dental plaque removal in children with Down syndrome in comparison to children with no special needs. A randomized clinical trial was performed on 48 children aged 6–9 years old. Participants were divided into two groups (n = 24, children with no special needs or with Down syndrome). Each group was divided into two subgroups (customized and conventional toothbrush). Plaque accumulation was evaluated using Turesky modification of the Quigley–Hein plaque index (TMQHPI) at four times (pre-brushing (T0), post-brushing at baseline (T1), 1 week (T2) and 3 weeks (T3)), and the modified gingival index (MGI) was used to evaluate the gingivitis at three times (T0, T2 and T3). Data were statistically analyzed. Plaque accumulation and gingivitis decreased significantly for all groups between T0 and T3 (p < 0.05). Both customized groups demonstrated significant lower plaque accumulation compared to conventional groups (p < 0.05) at T1, T2 and T3 and significant lower gingivitis at T3. Customizing the toothbrush handle improved child’s ability for plaque control, especially in children with Down syndrome.

A Repeated State of Acidification Enhances the Anticariogenic Biofilm Activity of Glass Ionomer Cement Containing Fluoro-Zinc-Silicate Fillers

This study aimed to evaluate the anticariogenic biofilm activity of a novel zinc-containing glass ionomer cement, Caredyne Restore (CR), using a flow-cell system that reproduces Stephan responses. Streptococcus mutans biofilms were cultured on either CR or hydroxyapatite (HA) discs mounted on a modified Robbins device. The media were allowed to flow at a speed of 2 mL/min for 24 h while exposed to an acidic buffer twice for 30 min to mimic dietary uptake. Acid exposure enhanced biofilm inhibition in the CR group, which showed 2.6 log CFU/mm² in viable cells and a 2 log copies/mL reduction in total cells compared to the untreated group after 24 h of incubation, suggesting enhanced anticariogenic activity due to the release of fluoride and zinc ions. However, there was no difference in the number of viable and total cells between the two experimental groups after 24 h of incubation in the absence of an acidic environment. The anticariogenic biofilm activity of CR occurs in acidic oral environments, for example in the transient pH drop following dietary uptake. CR restorations are recommended in patients at high risk of caries due to hyposalivation, difficulty brushing, and frequent sugar intake.

Comparative Evaluation of the Effectiveness of 40% Miswak Mouthwash and 0.12% Chlorhexidine Mouthwash in Treating Gingivitis: A Blinded, Randomised Clinical Trial

PURPOSE

To assess the effectiveness of a 40% miswak compared to a 0.12% chlorhexidine mouthwash.

MATERIALS AND METHODS

A total of 60 patients aged 20-55 years who attended the Periodontics Clinics at the College of Dentistry, Al-Iraqia University, Baghdad, Iraq, were allocated into 2 groups to use either 40% miswak mouthwash or 0.12% chlorhexidine gluconate Kin Gingival (Laboratorios KIN) twice daily for 2 months. Gingival, bleeding, and plaque indices were assessed.

RESULTS

There were statistically significant differences between the effectiveness of miswak and chlorhexidine mouthwashes in terms of gingivitis. The means of gingival, bleeding, and plaque indices using miswak mouthwash were 1.2, 0.4, and 0.53, respectively, i.e. indicating lower effectiveness, than when 0.12% chlorhexidine mouthwash was used (0.87, 0.43, 0.23, respectively).

CONCLUSION

Miswak mouthwash is a good oral hygiene agent especially for long-term use even if its efficacy is lower than chlorhexidine mouthwash.

Development of a herbal mouthwash containing a mixture of essential oils and plant extracts and in vitro testing of its antimicrobial efficiency against the planktonic and biofilm-enclosed cariogenic bacterium Streptococcus mutans

A herbal mouthwash containing essential oils of holy basil and mountain tea, extracts of St John's wort and European goldenrod (Bucovia™) and cetylpyridinium chloride, was developed and in vitro tested for its efficiency against biofilm formation by Streptococcus mutans, together with its eradicating activity against already preformed (48 h with saccharose) streptococcal biofilm. The minimum inhibitory (MIC) and bactericidal concentrations (MBC) of the final formulation, as well as of its individual components, were initially determined. The results revealed that the mouthwash needed to be applied at two-times its MIC (0.63% v.v^-1) to completely inhibit biofilm formation by S. mutans, which was otherwise capable of developing a robust biofilm on the tested surface. Once fully developed, the matrix of the biofilm was found to contain a significant amount of exopolysaccharides protecting the cells, being impossible to eradicate even when exposed to pure mouthwash for 15 min, highlighting the great recalcitrance of biofilm-embedded S. mutans.

Recent Development of Active Ingredients in Mouthwashes and Toothpastes for Periodontal Diseases

Periodontal diseases like gingivitis and periodontitis are primarily caused by dental plaque. Several antiplaque and anti-microbial agents have been successfully incorporated into toothpastes and mouthwashes to control plaque biofilms and to prevent and treat gingivitis and periodontitis. The aim of this article was to review recent developments in the antiplaque, anti-gingivitis, and anti-periodontitis properties of some common compounds in toothpastes and mouthwashes by evaluating basic and clinical studies, especially the ones published in the past five years. The common active ingredients in toothpastes and mouthwashes included in this review are chlorhexidine, cetylpyridinium chloride, sodium fluoride, stannous fluoride, stannous chloride, zinc oxide, zinc chloride, and two herbs—licorice and curcumin. We believe this comprehensive review will provide useful up-to-date information for dental care professionals and the general public regarding the major oral care products on the market that are in daily use.

Lactoferrin and oral pathologies: a therapeutic treatment

The oral cavity is a non-uniform, extraordinary environment characterized by mucosal, epithelial, abiotic surfaces and secretions as saliva. Aerobic and anaerobic commensal and pathogenic microorganisms colonize the tongue, teeth, jowl, gingiva, and periodontium. Commensals exert an important role in host defenses, while pathogenic microorganisms can nullify this protective function causing oral and systemic diseases. Every day, 750-1000 mL of saliva, containing several host defense constituents including lactoferrin (Lf), are secreted and swallowed. Lf is a multifunctional iron-chelating cationic glycoprotein of innate immunity. Depending on, or regardless of its iron-binding ability, Lf exerts bacteriostatic, bactericidal, antibiofilm, antioxidant, antiadhesive, anti-invasive, and anti-inflammatory activities. Here, we report the protective role of Lf in different oral pathologies, such as xerostomia, halitosis, alveolar or maxillary bone damage, gingivitis, periodontitis, and black stain. Unlike antibiotic therapy, which is ineffective against bacteria that are within a biofilm, adherent, or intracellular, the topical administration of Lf, through its simultaneous activity against microbial replication, biofilms, adhesion, and invasiveness, as well as inflammation, has been proven to be efficient in the treatment of all known oral pathologies without any adverse effects.

Lactobacillus reuteri AN417 cell-free culture supernatant as a novel antibacterial agent targeting oral pathogenic bacteria

Lactobacillus reuteri AN417 is a newly characterized probiotic strain. The activity of AN417 against oral pathogenic bacteria is unknown. We investigated the antibacterial activity of cell-free L. reuteri AN417 culture supernatant (LRS) against three oral pathogens: Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus mutans. P. gingivalis and F. nucleatum have been implicated in periodontal disease, whereas S. mutans causes dental caries. Exposing these oral pathogenic bacteria to LRS significantly reduced their growth rates, intracellular ATP levels, cell viability, and time-to-kill. The minimal inhibitory volume of LRS was 10% (v/v) against P. gingivalis, 20% (v/v) for F. nucleatum, and 30% (v/v) for S. mutans. LRS significantly reduced the integrity of biofilms and significantly suppressed the expression of various genes involved in P. gingivalis biofilm formation. The L. reuteri AN417 genome lacked genes encoding reuterin, reuteran, and reutericyclin, which are major antibacterial compounds produced in L. reuteri strains. LRS treated with lipase and α-amylase displayed decreased antibacterial activity against oral pathogens. These data suggest that the antibacterial substances in LRS are carbohydrates and/or fatty acid metabolites. Our results demonstrate that LRS has antimicrobial activity against dental pathogenic bacteria, highlighting its potential utility for the prevention and treatment of P. gingivalis periodontal disease.

Effect of Citrus aurantium L. Essential Oil on Streptococcus mutans Growth, Biofilm Formation and Virulent Genes Expression

In an oral cavity, dental caries, periodontal disease, and endodontic lesions are caused by well-known bacterial and fungal pathogens. Essential oils (EOs) have demonstrated antimicrobial activity suggesting their use for oral hygiene. The goal of this study was to evaluate the interaction of bitter orange flower (Citrus aurantium L.) essential oil with cariogenic bacteria Streptococcus mutans and human gingival epithelial cells. After extraction, the chemical composition of the essential oil was analyzed by gas chromatography, and its antimicrobial activity was evaluated against the growth and the expression of virulent genes in S. mutans. Finally, the effects of this essential oil on human gingival epithelial cell adhesion and growth were assessed using cell adhesion and proliferation assays. We showed that the major constituents of the tested essential oil were limonene, linalool, and β-ocimene. The essential oil reduced the growth of S. mutans, and decreased expression of comC, comD, comE, gtfB, gtfC, and gbpB genes. It should, however, be noted that essential oil at high concentration was toxic to gingival epithelial cells. Overall, this study suggests that C. aurantium L. essential oil could be used to prevent/control oral infections.

Evaluation of periodontal indices in young adults submitted to chlorhexidine 0.12% mouthwash: a randomized clinical trial

Abstract Introduction Gingivitis is a gingival inflammation which can often be treated with oral hygiene such as brushing, flossing, and an antiseptic mouthwash. Objective The aim of this randomized clinical trial was to clinically evaluate the effectiveness of 0.12% chlorhexidine (CHX) solution as an anti-inflammatory agent and for reducing the presence of plaque and inflammation in young adults. Material and method Thirty patients with gingivitis aged 18 to 30 years with a probing depth ≤ 3 mm and a minimum of 20 teeth in the whole mouth were selected and evaluated at baseline and 30 days after treatment. Periodontal clinical parameters were verified: plaque index (PI), gingival index (GI), Simplified Oral Hygiene Index (OHI-S), Simplified Debris Index (DI-S), and Simplified Calculus Index (CI-S) Patients were then randomly allocated into two groups: CHX Group, received chlorhexidine 0.12% labeled as solution 1, and Placebo Group, received saline solution labeled as solution 2. Both groups were included in a hygiene program and received mouthwash. Result Statistically significant differences between CHX and Placebo groups were observed for the variables PI, GI, DI-S, CI-S, and OHI-S (p<0.05 - Paired T Test) after 30 days. The CHX group presented improved GI compared to Placebo at 30 days. Chlorhexidine 0.12% was efficient in the control of periodontium inflammation. Conclusion It can be concluded that chlorhexidine as a mouthwash is efficient in improving periodontal indices in young adults, but it is still controversial whether age can influence GI and OHI-S.

Mouthwash Based on Ozonated Olive Oil in Caries Prevention: A Preliminary In-Vitro Study

(1) Background: Ozone (O3) proved to oxidize organic and inorganic compounds, and its efficacy against bacteria, viruses and fungi plasma membranes was of interest. Ozone vehicle can be a gaseous form, ozonated water or ozonized oil. The aim of this in-vitro study was to evaluate the efficacy of ozonated olive oil against Streptococcus mutans. (2) Methods: Two different commercial mouthwashes were tested: Ialozon Blu (IB) (Gemavip, Cagliari, Italy), with ozonated olive oil, and Ialozon Rose (IR) (Gemavip, Cagliari, Italy), with ozonated olive oil, hyaluronic acid and vitamin E. All formulates were analyzed in a dilution range from 2- to 256-folds in saline solution, as to reproduce the salivary dilution. Streptococcus mutans CIP103220 strain was used for the antimicrobial susceptibility test, and the Kirby-Bauer inhibition method was performed to evaluate the Minimum Inhibitory (MIC), Minimum Bactericidal (MBC), and Minimum Biofilm Inhibitory Concentration (MBIC). (3) Results: Both formulates showed the same antimicrobial activity. MIC, MBC, and MBIC were observed for dilution factors of 1/32, 1/8 and 1/8, respectively. The mean value of inhibition zone diameter was 16.5 mm for IB, and 18 mm for IR. (4) Conclusions: The results suggested that ozonized olive oil formulates were able to inactivate Streptococcus mutans avoiding the salivary dilution effect in the oral cavity.

Rhamnolipids and surfactin inhibit the growth or formation of oral bacterial biofilm

Background

Bacteria survive in various environments by forming biofilms. Bacterial biofilms often cause significant problems to medical instruments and industrial processes. Techniques to inhibit biofilm formation are essential and have wide applications. In this study, we evaluated the ability of two types of biosurfactants (rhamnolipids and surfactin) to inhibit growth and biofilm formation ability of oral pathogenic bacteria such as Aggregatibacter actinomycetemcomitans, Streptococcus mutans, and Streptococcus sanguinis.

Results

Rhamnolipids inhibited the growth and biofilm formation ability of all examined oral bacteria. Surfactin showed effective inhibition against S. sanguinis ATCC10556, but lower effects toward A. actinomycetemcomitans Y4 and S. mutans UA159. To corroborate these results, biofilms were observed by scanning electron microscopy (SEM) and confocal microscopy. The observations were largely in concordance with the biofilm assay results. We also attempted to determine the step in the biofilm formation process that was inhibited by biosurfactants. The results clearly demonstrated that rhamnolipids inhibit biofilm formation after the initiation process, however, they do not affect attachment or maturation.

Conclusions

Rhamnolipids inhibit oral bacterial growth and biofilm formation by A. actinomycetemcomitans Y4, and may serve as novel oral drug against localized invasive periodontitis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-020-02034-9.