The effects of essential oil mouthrinses with or without alcohol on plaque and gingivitis: a randomized controlled clinical study

Quantitative analysis of the effects of essential oil mouthrinses on clinical plaque microbiome: a parallel-group, randomized trial

BACKGROUND

The rich diversity of microorganisms in the oral cavity plays an important role in the maintenance of oral health and development of detrimental oral health conditions. Beyond commonly used qualitative microbiome metrics, such as relative proportions or diversity, both the species-level identification and quantification of bacteria are key to understanding clinical disease associations. This study reports the first-time application of an absolute quantitative microbiome analysis using spiked DNA standards and shotgun metagenome sequencing to assess the efficacy and safety of product intervention on dental plaque microbiome.

METHODS

In this parallel-group, randomized clinical trial, essential oil mouthrinses, including LISTERINE® Cool Mint Antiseptic (LCM), an alcohol-containing prototype mouthrinse (ACPM), and an alcohol-free prototype mouthrinse (AFPM), were compared against a hydroalcohol control rinse on clinical parameters and the oral microbiome of subjects with moderate gingivitis. To enable a sensitive and clinically meaningful measure of bacterial abundances, species were categorized according to their associations with oral conditions based on published literature and quantified using known amounts of spiked DNA standards.

RESULTS

Multivariate analysis showed that both LCM and ACPM shifted the dysbiotic microbiome composition of subjects with gingivitis to a healthier state after 4 weeks of twice-daily use, resembling the composition of subjects with clinically healthy oral conditions recruited for observational reference comparison at baseline. The essential oil-containing mouthrinses evaluated in this study showed statistically significant reductions in clinical gingivitis and plaque measurements when compared to the hydroalcohol control rinse after 6 weeks of use.

CONCLUSIONS

By establishing a novel quantitative method for microbiome analysis, this study sheds light on the mechanisms of LCM mouthrinse efficacy on oral microbial ecology, demonstrating that repeated usage non-selectively resets a gingivitis-like oral microbiome toward that of a healthy oral cavity.

TRIAL REGISTRATION

The trial was registered on ClinicalTrials.gov on 10/06/2021. The registration number is NCT04921371.

Quantitative analysis of the effects of brushing, flossing, and mouthrinsing on supragingival and subgingival plaque microbiota: 12-week clinical trial

BACKGROUND

Translational microbiome research using next-generation DNA sequencing is challenging due to the semi-qualitative nature of relative abundance data. A novel method for quantitative analysis was applied in this 12-week clinical trial to understand the mechanical vs. chemotherapeutic actions of brushing, flossing, and mouthrinsing against the supragingival dental plaque microbiome. Enumeration of viable bacteria using vPCR was also applied on supragingival plaque for validation and on subgingival plaque to evaluate interventional effects below the gingival margin.

METHODS

Subjects with gingivitis were enrolled in a single center, examiner-blind, virtually supervised, parallel group controlled clinical trial. Subjects with gingivitis were randomized into brushing only (B); brushing and flossing (BF); brushing and rinsing with Listerine® Cool Mint® Antiseptic (BA); brushing and rinsing with Listerine® Cool Mint® Zero (BZ); or brushing, flossing, and rinsing with Listerine® Cool Mint® Zero (BFZ). All subjects brushed twice daily for 1 min with a sodium monofluorophosphate toothpaste and a soft-bristled toothbrush. Subjects who flossed used unflavored waxed dental floss once daily. Subjects assigned to mouthrinses rinsed twice daily. Plaque specimens were collected at the baseline visit and after 4 and 12 weeks of intervention. Bacterial cell number quantification was achieved by adding reference amounts of DNA controls to plaque samples prior to DNA extraction, followed by shallow shotgun metagenome sequencing.

RESULTS

286 subjects completed the trial. The metagenomic data for supragingival plaque showed significant reductions in Shannon-Weaver diversity, species richness, and total and categorical bacterial abundances (commensal, gingivitis, and malodor) after 4 and 12 weeks for the BA, BZ, and BFZ groups compared to the B group, while no significant differences were observed between the B and BF groups. Supragingival plaque vPCR further validated these results, and subgingival plaque vPCR demonstrated significant efficacy for the BFZ intervention only.

CONCLUSIONS

This publication reports on a successful application of a quantitative method of microbiome analysis in a clinical trial demonstrating the sustained and superior efficacy of essential oil mouthrinses at controlling dental plaque compared to mechanical methods. The quantitative microbiological data in this trial also reinforce the safety and mechanism of action of EO mouthrinses against plaque microbial ecology and highlights the importance of elevating EO mouthrinsing as an integral part of an oral hygiene regimen.

TRIAL REGISTRATION

The trial was registered on ClinicalTrials.gov on 31/10/2022. The registration number is NCT05600231.

Morphological changes and viability of Streptococcus mutans biofilm treated with erythrosine: A confocal laser scanning microscopy analysis

Antimicrobial photodynamic therapy (a-PDT) is a modality that aims to induce microorganisms through visible light, a photosensitizer, and molecular oxygen. This therapy has shown promising results in controlling cariogenic biofilm in vitro and in vivo counterparts. This study investigated bacterial viability and morphological characterization of Streptococcus mutans mature biofilms after combination of erythrosine and a high potency dental curing light. Biofilms were formed on saliva-coated hydroxyapatite disks in batch culture. The samples were performed in triplicates. Fresh medium was replaced daily for five days and treated using 40 μM of E activated by HL 288 J/cm2 and total dose of 226 J at 1200 mW/cm2. Phosphate buffer saline and 0.12% of chlorhexidine were used as negative and positive control, respectively. After treatment, biofilms were assessed for microbial viability and morphological characterization by means of bio-volume and thickness. COMSTAT software was used for image analysis. Data were analyzed using two-way ANOVA followed by Tukey test with significance level 5%. The application of a-PDT and CHX treatments decreased S. mutans bacterial viability. The image analysis showed more red cells on biofilms when compared to other groups, demonstrating photobacterial killing. Erythrosine irradiated with a high potency curing light can potentially act as an antimicrobial tool in the treatment of cariogenic biofilms. The morphology and viability of microorganisms were impacted after treatment. Treatment with photodynamic therapy may be able to reduce the bio-volume and viability of bacteria present in biofilms. CLINICAL RELEVANCE AND RESEARCH HIGHLIGHTS: The use of the a-PDT technique has been applied in dentistry with satisfactory results. Some applications of this technique are in stomatology and endodontics. In the present study, we sought to understand the use of photodynamic therapy in the control of biofilm and the results found are compatible with the objective of microbiological control proposed by this technique, thus raising the alert for future studies in vivo using the combination of a-PDT with erythrosine, since they are easily accessible materials for the dental surgeon and can be applied in clinical practice.

A Dive into Delivery of Oral Hygiene Advice Based on the Personalized Oral Hygiene Advice Model

Oral health's impact on overall well-being highlights the importance of preventive measures through effective oral hygiene practices. Currently, there is growing recognition of the need for customized oral hygiene advice depending on the patient's unique needs and circumstances. This narrative review addresses the gap in understanding the significance of personalized guidance through the proposal of the Personalized Oral Hygiene Advice Model (POHAM) as a comprehensive guide for oral health professionals. This model was developed to adapt to evolving patient demographics and diverse challenges, promoting a patient-centric and effective oral health approach. The POHAM comprises a flow chart of strategies from establishing a good rapport with patients, conducting comprehensive assessment through history-taking, psychosocial and technology proficiency evaluation, tailored education modules, and customized oral care product recommendations until the reassessment. These strategies aim to enhance patient engagement and adherence, as well as act as a guide for oral health professionals to use in the clinical setting before and during the course of oral treatment. Nevertheless, continued research, education, and technological advancements are needed to realize the full potential of personalized oral hygiene strategies, ensuring a transformative and sustainable oral healthcare landscape.

Changes in Oral Health and Dental Esthetic in Smokers Switching to Combustion-Free Nicotine Alternatives: Protocol for a Multicenter and Prospective Randomized Controlled Trial

BACKGROUND

Although the detrimental effects of conventional combustible cigarettes on oral health and dental esthetics are well known, there is limited information about the long-term impact of combustion-free nicotine alternatives (C-F NA) such as e-cigarettes or heated tobacco products.

OBJECTIVE

This multicenter, prospective, 3-parallel-arm randomized controlled trial will investigate whether switching from combustible cigarettes to C-F NA will lead to measurable improvements in oral health parameters and dental esthetics over 18 months in adult smokers with limited gum disease.

METHODS

Regular smokers not intending to quit and without clinical signs of periodontitis will be randomly assigned (1:4 ratio) to either standard of care with brief cessation advice (control group; arm A) or C-F NA use (intervention group; arm B). The study will also include a reference group of never smokers (reference group; arm C). The primary end point is the change in the Modified Gingival Index (MGI) score from baseline between the control arm (arm A) and the intervention arm (arm B) at the 18-month follow-up. In addition, the study will analyze the within- and between-group (arms A, B, and C) changes in MGI assessment, plaque imaging, dental shade quantitation, tooth stain scores, and oral health-related quality of life questionnaires measured at each study time point. All participants will attend a total of 7 clinic visits: screening, enrollment, and randomization (visit 0); baseline visit-day 14 (visit 1); day 90 (visit 2); day 180 (visit 3); day 360 (visit 4); and day 540 (visit 5). This multicenter study will be conducted in 4 dental clinics in 4 countries. The statistical analysis will involve descriptive statistics for continuous and categorical data. Primary end points will undergo tests for normality and, based on distribution, either a 2-sided t test or Mann-Whitney U test. Linear mixed model with random factors center and study arms by center will also be applied. Secondary end points, including MGI assessment and quality of life, will be subjected to similar tests and comparisons. Only if one value of the parameter MGI is missing after day 1, the last available observation will be carried forward. The analysis will be performed on the substituted data. Secondary parameters will not have missing value replacement.

RESULTS

Participant recruitment began in October 2021, and enrollment was completed in June 2023. Results will be reported in 2025.

CONCLUSIONS

This will be the first study to provide key insights into oral health benefits or risks associated with using C-F NA in smokers who are seeking alternatives to cigarette smoking.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04649645; https://clinicaltrials.gov/ct2/show/NCT04649645.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/53222.

Efficacy of flossing and mouth rinsing regimens on plaque and gingivitis: a randomized clinical trial

BACKGROUND

To investigate the effects of combinations of mechanical (brushing and flossing) and chemotherapeutic regimens which included essential oils (EO) non-alcohol and alcohol-containing mouthrinses compared to brushing only in the prevention and reduction of plaque, gingivitis, and gingival bleeding.

METHODS

This was a randomized, virtually supervised, examiner blind, controlled clinical trial. Following informed consent and screening, subjects (N = 270) with gingivitis were randomly assigned to one of the following regimens: (1) Brush Only (B, n = 54); (2) Brush/Rinse (EO alcohol-containing mouthrinse) (BA, n = 54); (3) Brush/Rinse (EO non-alcohol containing mouthrinse) (BZ, n = 54); (4) Brush/Floss (BF, n = 54); (5) Brush/Floss/Rinse (EO non-alcohol containing mouthrinse) (BFZ, n = 54). Unflavored waxed dental floss (REACH unflavored waxed dental floss), and fluoridated toothpaste (Colgate Cavity Protection) were used. Examinations included oral hard and soft tissue, plaque, gingivitis, gingival bleeding, probing depth and bleeding on probing.

RESULTS

After 12 weeks, both BA and BZ and the BFZ group were superior in reducing interproximal plaque (30.8%, 18.2%, 16.0%, respectively), gingivitis (39.0%, 36.9%, 36.1%, respectively), and bleeding (67.8%, 73.6%, 79.8%, respectively) compared to B. The BF group did not provide significant reductions in interproximal plaque but did reduce interproximal gingivitis (5.1%, p = 0.041) at Week 4 and bleeding at Weeks 4 and 12 (34.6%, 31.4%, p < 0.001 respectively) compared to B. The BFZ group did not significantly reduce interproximal plaque, gingivitis or bleeding compared to BZ.

CONCLUSIONS

This study demonstrated that the addition of EO non-alcohol containing mouthrinse to the manual toothbrushing and flossing regimen further reduces plaque, gingivitis and bleeding showing that addition of EO mouthrinses (alcohol or non-alcohol containing) to the oral hygiene regimen provides sustained reductions in plaque to help maintain gingival health after a dental prophylaxis. Dental professional recommendation of the addition of an EO non-alcohol containing mouthrinse to daily oral hygiene routines of brushing or brushing and flossing should be considered to aid supragingival plaque control and improve gingivitis prevention.

STUDY REGISTRY NUMBER

NCT05600231.

Side effects and short effects of using three common mouthwashes on oral health and quality of life: A quasi-experimental study

BACKGROUND

Antiseptic mouthwashes are useful adjuncts to daily brushing and flossing for the control of dental plaque and gingivitis. The objective of the present study was to compare the effect of three mouthwashes: chlorhexidine, essential oils and cetylpyridinium chloride on oral health-related quality of life, gingival health, tongue coating and also to compare their potential side effects after 2-week consumption.

METHODS

Sixty participants were enrolled in this study and were divided into four groups (three mouthwash groups plus no mouthwash group). At the beginning, scaling and cleaning were performed and the following parameters were recorded: oral health impact profile (OHIP-5) questionnaire, tongue coating index, modified gingival index, calculus surface index, modified Lobene stain index and a questionnaire for side effects. Each group has followed up in 2 weeks. Data were analysed using paired t-test, ANOVA, Fisher's exact test and Pearson chi-square.

RESULTS

At the end of second week, all three mouthwashes significantly improved OHIP-5 score and reduced modified gingival index whereas essential oils and cetylpyridinium chloride significantly reduced tongue coating index when compared to control group (p < 0.05). The differences between four groups were significant for calculus formation, dental staining and reported burning sensation and changes of taste sensation and perception (p < 0.05).

CONCLUSION

The use of all three mouthwashes has been effective in controlling and reducing gingivitis and tongue coating; however, it appeared that essential oils has the minimum and Chlorhexidine has the maximum side effects. Moreover, the use of all three mouthwashes has been examined to improve the quality of life. Overall, essential oils mouthwash has the best performance among these three mouthwashes.

Potential Application of the Plant-Derived Essential Oils for Atherosclerosis Treatment: Molecular Mechanisms and Therapeutic Potential

Essential oils (EOs) are complex secondary metabolites identified in many plant species. Plant-derived EOs have been widely used in traditional medicine for centuries for their health-beneficial effects. Some EOs and their active ingredients have been reported to improve the cardiovascular system, in particular to provide an anti-atherosclerotic effect. The objective of this review is to highlight the recent research investigating the anti-inflammatory, anti-oxidative and lipid-lowering properties of plant-derived EOs and discuss their mechanisms of action. Also, recent clinical trials exploring anti-inflammatory and anti-oxidative activities of EOs are discussed. Future research on EOs has the potential to identify new bioactive compounds and invent new effective agents for treatment of atherosclerosis and related diseases such as diabetes, metabolic syndrome and obesity.

A Cross-Sectional Study to Evaluate Dental Professionals' Knowledge of Antiplaque Mouth Rinse Agents and their Application in Periodontal Practice

Background

Mouth rinse agents reduce inflammation and microbial burden, improving periodontal clinical parameters. Yet, improper clinical use of these compounds might have several deleterious repercussions. Given the lack of research on the knowledge and application of antiplaque mouth rinse agents, this research was conducted.

Methods

The research is an electronic survey wherein responses were gathered for ten items with predetermined answers in addition to covariate data. The questions were conceived to illuminate the level of knowledge possessed by dental professionals and their utilization pattern in periodontal practice. The data gathered underwent quantitative statistical analysis.

Results

Participants in the study included 100 dental professionals from various disciplines, all of whom agreed that mouth rinses are a vital adjuvant in periodontal therapy. Most acknowledged being aware of the various mouth rinse agents, but their knowledge and application of mouth rinses were largely confined to chlorhexidine gluconate, with little consideration being given to alternative antiplaque agents.

Conclusion

Little knowledge exists among dental professionals regarding mouth rinse agents and their appropriate application. Dental schools, clinical advisory organizations, and other establishments could educate dental professionals on the specific guidelines for utilizing antiplaque mouth rinses in a dental context, especially as an adjunct to periodontal therapy.

Dynamic killing effectiveness of mouthrinses and a D-enantiomeric peptide on oral multispecies biofilms grown on dental restorative material surfaces

OBJECTIVE

To evaluate the dynamics of killing of oral multispecies biofilms grown on dental restorative materials by commercially available mouthrinses and a D-enantiomeric peptide.

METHODS

Four composite resins (3M Supreme, 3M Supreme flow, Kerr Sonicfill, and Shofu Beautifil II) and one glass ionomer (GC Fuji II) were used as restorative materials. Plaque biofilms were grown on the surfaces of restorative material discs for 1 week. The surface roughness and biofilm attachment were assessed by atomic force microscopy and scanning electron microscopy. One-week-old biofilms grown anaerobically at 37°C were exposed to each of five solutions for one minute (twice daily for seven days): Listerine Total care and Paroex Gum mouthrinses, 0.12% chlorhexidine, 0.001% D-enantiomeric peptide DJK-5, and sterile water. The dynamic variation of the biovolume of the biofilms and the percentage of dead bacteria were monitored and analyzed using confocal laser scanning microscopy.

RESULTS

All restorative materials had similar surface roughness with intact biofilm attachment. The percentage of dead bacteria and biovolume of biofilms treated by each oral rinse solution remained constant between days 1 and 7, with no statistically significant difference. DJK-5 showed the highest percentage of dead bacteria (up to 75.7%; cf. ∼20-40% for other mouthrinses) of all solutions tested within 7 days.

CONCLUSIONS

DJK-5 outperformed conventional mouthrinses in killing bacteria in oral multispecies biofilms grown on dental restorative materials.

CLINICAL SIGNIFICANCE

The antimicrobial peptide DJK-5 is effective against oral biofilms and serves as a promising candidate for the development of future mouthrinses to improve long-term oral hygiene.

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.

Extraction of High-Value Chemicals from Plants for Technical and Medical Applications

Plants produce a variety of high-value chemicals (e.g., secondary metabolites) which have a plethora of biological activities, which may be utilised in many facets of industry (e.g., agrisciences, cosmetics, drugs, neutraceuticals, household products, etc.). Exposure to various different environments, as well as their treatment (e.g., exposure to chemicals), can influence the chemical makeup of these plants and, in turn, which chemicals will be prevalent within them. Essential oils (EOs) usually have complex compositions (>300 organic compounds, e.g., alkaloids, flavonoids, phenolic acids, saponins and terpenes) and are obtained from botanically defined plant raw materials by dry/steam distillation or a suitable mechanical process (without heating). In certain cases, an antioxidant may be added to the EO (EOs are produced by more than 17,500 species of plants, but only ca. 250 EOs are commercially available). The interesting bioactivity of the chemicals produced by plants renders them high in value, motivating investment in their production, extraction and analysis. Traditional methods for effectively extracting plant-derived biomolecules include cold pressing and hydro/steam distillation; newer methods include solvent/Soxhlet extractions and sustainable processes that reduce waste, decrease processing times and deliver competitive yields, examples of which include microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and supercritical CO2 extraction (scCO2). Once extracted, analytical techniques such as chromatography and mass spectrometry may be used to analyse the contents of the high-value extracts within a given feedstock. The bioactive components, which can be used in a variety of formulations and products (e.g., displaying anti-aging, antibacterial, anticancer, anti-depressive, antifungal, anti-inflammatory, antioxidant, antiparasitic, antiviral and anti-stress properties), are biorenewable high-value chemicals.

Evaluation of the In Vitro Antiparasitic Effect of the Essential Oil of Cymbopogon winterianus and Its Chemical Composition Analysis

Cymbopogon winterianus, known as “citronella grass”, is an important aromatic and medicinal tropical herbaceous plant. The essential oil of C. winterianus (EOCw) is popularly used to play an important role in improving human health due to its potential as a bioactive component. The present study aimed to identify the components of the essential oil of C. winterianus and verify its leishmanicidal and trypanocidal potential, as well as the cytotoxicity in mammalian cells, in vitro. The EOCw had geraniol (42.13%), citronellal (17.31%), and citronellol (16.91%) as major constituents. The essential oil only exhibited significant cytotoxicity in mammalian fibroblasts at concentrations greater than 250 μg/mL, while regarding antipromastigote and antiepimastigote activities, they presented values considered clinically relevant, since both had LC50 < 62.5 μg/mL. It can be concluded that this is a pioneer study on the potential of the essential oil of C. winterianus and its use against the parasites T. cruzi and L. brasiliensis, and its importance is also based on this fact. Additionally, according to the results, C. winterianus was effective in presenting values of clinical relevance and low toxicity and, therefore, an indicator of popular use.

Evaluation of the effectiveness of a novel mouth rinse containing hyaluronic acid and hydrogen peroxide on gingivitis: A randomized pilot controlled trial

Objective

To evaluate and compare the effectiveness of a mouth rinse with hydrogen peroxide (H₂O₂) and hyaluronic acid (HA) versus a placebo mouth rinse on gingivitis.

Material and methods

This was a 21‐day, double blind, randomized, two‐arm parallel allocation placebo‐controlled trial of 50 study participants with a diagnosis of plaque‐induced gingivitis. Patients were randomly allocated to the test group or the placebo group and were assessed at three time points over the course of the study by the same operator, at baseline (T0), 7 days (T1), and 21 days follow‐up (T2). Primary outcomes of the trial were improvement in gingivitis and plaque accumulation.

Results

In both groups there was a decrease in gingival and plaque indices but the combination of the two actives (H₂O₂/HA) proved to be more effective against gingivitis (p = 0.001). Regarding plaque index, the differences between the test product and placebo were not statistically significant (p = 0.084). Besides, the new mouthwash was considered palatable, no adverse events were registered over the 21‐day period.

Conclusions

The H₂O₂ + HA product was more effective in reducing gingivitis when compared to a placebo while no differences were observed for plaque accumulation.

Antibiofilm effects of Thymus vulgaris and Hyptis spicigera essential oils on cariogenic bacteria

Aim: The inhibitory and antibiofilm effects of Thymus vulgaris (EOTv) and Hyptis spicigera essential oils (EOHs) on cariogenic microorganisms were evaluated. Materials & methods: The chemical characterization of EOTv was performed by gas chromatography/mass spectrometry. Streptococcus mutans, Streptococcus gordonii, Streptococcus sanguinis, Streptococcus mitis, Streptococcus sobrinus, Lactobacillus acidophilus and Actinomyces naeslundii were used for agar diffusion assays and determination of minimal inhibitory and minimal bactericide concentrations. In addition, 20 streptococci and lactobacilli clinical isolates were also tested. The effects of essential oil on microbial initial biofilm formation and on preformed microcosm biofilm formed from human saliva were studied. Results & conclusion: Both essential oils had inhibitory effects on the cariogenic species and reduced the bacterial adherence to dental enamel. Essential oils were able to disrupt preformed microcosm biofilms. Thymus vulgaris and Hyptis spicigera essential oils have potential to be used in the development of formulations to the control of cariogenic biofilms.

Efficacy of Essential Oil Mouthwashes With and Without Alcohol on the Plaque Formation: A Randomized, Crossover, Double-Blinded, Clinical Trial

BACKGROUND

Essential oil (EO) mouthwash has been considered as one of the effective chemical agents as an adjunct to mechanical plaque control, without adverse effects compared with chlorhexidine (pigmentation, changes of taste, and formation of supragingival calculus), which limits its continuous use. New EO alcohol-based has emerged with questions regarding contraindications for its daily use.

OBJECTIVE

To compare the efficacy of EO mouthwashes with and without alcohol on the early supragingival and subgingival plaque formation using a plaque-free zone score system.

METHODS

This study was a crossover, randomized, double-blind clinical trial. Eleven participants, totaling 396 sites of evaluation, remained 4 days with no mechanical oral hygiene control and only used EO mouthwash with (control) and without alcohol (test) during this period. The presence of the plaque-free zone was recorded every 24 hours. Friedman and Wilcoxon tests were used with a 5% significance level.

RESULTS

The control group showed a more significant number of buccal surfaces free of plaque at 48, 72, and 96 hours compared with the test group. Both groups presented satisfactory efficacy up to 72 hours with a significant difference in favor of the control group. The presence of subgingival plaque on both the proximal and free surfaces was significantly higher in the test group.

CONCLUSION

EO with alcohol presented better results in retarding the early supragingival and subgingival plaque formation compared with EO without alcohol.

Effectiveness of Alcohol-free Mouth Rinse Containing Essential Oils and Fluoride as an Oral Hygiene Adjunct among Pregnant Thai Women: A Randomized Clinical Trial

Aim:

This 3-month, double-blind, two-center, parallel, randomized controlled clinical trial compared the improvement of oral hygiene status from alcohol-free essential oils (EO) with 0.05% fluoride mouthwash to the control (0.05% fluoride mouthwash).

Materials and Methods:

One hundred and fifty-four pregnant women were clinically examined to determine Modified Gingival Index (MGI), Plaque Index (PI), and Winkel Tongue Coating Index (WTCI) at baseline, 2 weeks, and 3 months by calibrated examiners. After supragingival scaling and provision of a tooth brushing method, participants were randomly assigned to daily use of alcohol-free EO or the control rinse for 30s at bedtime. Repeated measures of analysis of variance (ANOVA) were performed to assess the effectiveness of alcohol-free EO with 0.05% fluoride mouthwash on MGI, PI, and WTCI scores.

Results:

One hundred and forty subjects completed the study. The dropout rate of 9.1% (n = 14) was mainly due to loss of follow-up. At baseline, no significant differences were observed between the intervention and the control groups for MGI (1.19±0.57 vs. 1.11±0.48, P = 0.371), PI (1.53±0.56 vs. 1.47±0.48, P = 0.439), and WTCI (0.88±0.48 vs. 0.88±0.50, P = 0.990). There was a statistically significant reduction of MGI, PI, and WTCI scores over time (P < 0.001). However, no significant differences were observed for between-group comparisons for all measured indices at any time point. No adverse effect was reported in either group.

Conclusion:

At the end of 3-month period, improvement of oral hygiene of pregnancy women in this study was evidence. However, the use of alcohol-free EO mouthwash as supplements to the daily oral hygiene did not provide a significant improvement in terms of plaque, gingival, and tongue coating indices.

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.

Preparation, characterisation and microbiological examination of Pickering nano-emulsions containing essential oils, and their effect on Streptococcus mutans biofilm treatment

Essential oils (EOs) are commonly applied in mouth care products like mouthwashes, mostly as an ethanolic solution or by usage of surfactants as solubilising agents. In this study, we present a formulation for preparation of Pickering nano-emulsions (PnE) of EOs as a novel form for application of EOs in mouth care. For the preparation of PnE, we have synthesised surface-modified silica nanoparticles with a mean diameter of 20 nm, as well as we have examined the effect of EOs concentration on PnE droplet size and stability. In vitro study of their effect on the Streptococcus mutans biofilm as the main pathogen of dental health problems has been performed. We have found that EOs in the PnE form has the highest effectiveness against biofilm formation. Diffusion through the biofilm model membrane was studied to explain this observation. We have found that PnEs have a better performance in the transportation of EOs trough model membrane than the ethanolic solutions and conventional emulsions (CEs).

Essential oils as topical anti-infective agents: A systematic review and meta-analysis

OBJECTIVE

This study summarized evidence on the efficacy and safety of essential oils (EOs) in the treatment of topical infections.

DESIGN AND SETTING

Systematic review of clinical trials conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. Electronic databases of the Cochrane, PubMed, EMBASE, Web of Science, and Scopus were searched from inception to November 2018.

INTERVENTION

Essential oil of any type, standard treatment and placebo.

MAIN OUTCOME MEASURES

Outcomes of the study include total acne count, acne severity index, reduction in total acne surface area, number of non-inflammatory acne lesions and inflammatory acne lesions, microbial cure rate, microbial decolonization rate, and new microbial emergence.

RESULTS

Non-significant but higher proportion of MRSA was cleared in EOs group (69% [95%CI: 34%, 96%]) compared to routine care (45% [95%CI: 36%, 53%]). Essential oils significantly lowered level of new MRSA emergence (9% [95% CI: 5%, 14%], I² = 86.59%) compared to routine care (53% [95%CI: 30%, 75%], I² = 86.59%). Four of the five studies on acne treatment showed equal or superior efficacy of EOs and the remaining one showed inferior efficacy to a control. In treatment of topical fungal infections, efficacy of essential oils were non-inferior compared to a standard treatment but superior to a placebo.

CONCLUSION

Essential oils could be considered as alternative treatment for acne, decolonization of MRSA, and topical fungal infections, yet the low quality and heterogeneity among the studies calls for further studies.

Dual-Targeting Approach Degrades Biofilm Matrix and Enhances Bacterial Killing

Biofilm formation is a key virulence factor responsible for a wide range of infectious diseases, including dental caries. Cariogenic biofilms are structured microbial communities embedded in an extracellular matrix that affords bacterial adhesion-cohesion and drug tolerance, making them difficult to treat using conventional antimicrobial monotherapy. Here, we investigated a multitargeted approach combining exopolysaccharide (EPS) matrix-degrading glucanohydrolases with a clinically used essential oils-based antimicrobial to potentiate antibiofilm efficacy. Our data showed that dextranase and mutanase can synergistically break down the EPS glucan matrix in preformed cariogenic biofilms, markedly enhancing bacterial killing by the antimicrobial agent (3-log increase versus antimicrobial alone). Further analyses revealed that an EPS-degrading/antimicrobial (EDA) approach disassembles the matrix scaffold, exposing the bacterial cells for efficient killing while concurrently causing cellular dispersion and "physical collapse" of the bacterial clusters. Unexpectedly, we found that the EDA approach can also selectively target the EPS-producing cariogenic bacteria Streptococcus mutans with higher killing specificity (versus other species) within mixed biofilms, disrupting their accumulation and promoting dominance of commensal bacteria. Together, these results demonstrate a dual-targeting approach that can enhance antibiofilm efficacy and precision by dismantling the EPS matrix and its protective microenvironment, amplifying the killing of pathogenic bacteria within.

Antimicrobial activity of mouth rinses against bacteria that initially colonizes dental’s surface

Abstract Introduction Much advertising in mouthwash is conveyed in all media appealing to the anti-plaque effect and rendering a disservice to the community. Mouth rinses are available over-the-count and differ on their compositions and antimicrobial effectiveness. Objective In this study, we evaluated the antimicrobial activity of 35 widely available mouth rinses against bacterial species involved in initiation of dental biofilm – Streptococcus gordonii, Streptococcus mitis, Streptococcus oralis, Streptococcus salivarius, and Streptococcus sanguinis. Material and method The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) of the evaluated mouth rinses were determined according to the Clinical & Laboratory Standards Institute protocols. Data were submitted to Kruskal-Wallis test and Mann-Whitney post hoc (α=0.05). Result About 70% of the mouth rinses achieved high antibacterial activity and 30%, a low antibacterial activity against all the species tested. The most ineffective mouth rinse showed antibacterial activity (MIC) at 1:1 dilution, while the most effective showed activity even at 1:2048 dilution, which may imply prolonged effect in the mouth. About 51% of mouth rinses showed bactericidal activity, and it was verified that cetylpyridinium chloride or chlorhexidine digluconate containing in the formulation were associated with the highest activity. Conclusion Most - but not all - mouth rinses commercially available are effective in inhibiting in vitro initial colonizers of dental surfaces.

Effect of a Toothpaste/Mouthwash Containing Carica papaya Leaf Extract on Interdental Gingival Bleeding: A Randomized Controlled Trial

Clinical research on herbal-based dentifrice +/− mouth rinse products is very limited compared with the plethora of research on conventional oral care products under normal oral hygiene conditions. The aim of this study was to determine the anti-inflammatory effects of a novel plant Carica papaya leaf extract (CPLE) on interdental bleeding in healthy subjects. In this randomized, single-blind parallel-design study, the eligible subjects were generally healthy non-smokers, aged 18–26, who exhibited healthy periodontal conditions upon study entry. The participants were equally randomized into the following four groups: CPLE dentifrice, CPLE dentifrice and mouthwash, sodium lauryl sulfate (SLS)-free enzyme-containing dentifrice and SLS-free enzyme-containing dentifrice with essential oil (EO) mouthwash. Subjects were instructed to brush their teeth twice a day without changing their other brushing habits. Interdental bleeding (BOIP) was measured from inclusion (T₀) until the fourth week (T₄) of the study. Clinical efficacy was assessed after one, two, three and four weeks of home use. The analyses compared BOIP between groups and were then restricted to participants with ≥70% and then ≥80% bleeding sites at T₀. Pairwise comparisons between groups were performed at T₀ and T₄, and a logistic regression identified correlates of gingival bleeding (T₄). Among 100 subjects (2273 interdental sites), the median percentage of bleeding sites per participant at T₀ was 65%. The bleeding sites dramatically decreased in all groups between T₀ and T₄ (relative variations from −54% to −75%, p < 0.01 for all). Gingival bleeding did not significantly differ between the CPLE dentifrice and the SLS-free dentifrice +/− EO mouthwash groups (from p = 0.05 to p = 0.86), regardless of the baseline risk level. Among the CPLE dentifrice users, fewer bleeding sites were observed when toothpaste and mouthwash were combined compared to bleeding sites in those who used toothpaste alone (21% vs. 32%, p = 0.04). CPLE dentifrice/mouthwash provides an efficacious and natural alternative to SLS-free dentifrice +/−EO-containing mouthwash when used as an adjunct to mechanical oral care to reduce interdental gingival inflammation.