The comparative effect of acidified sodium chlorite and chlorhexidine mouthrinses on plaque regrowth and salivary bacterial counts

Short- and long term antibacterial effects of a single rinse with different mouthwashes: A randomized clinical trial

Objectives

Reducing the microbial level in the aerosol created during dental procedures is essential to avoiding infections. The aim of this study was to examine the change in Streptococcus mutans (S. mutans) and the total bacterial load in human saliva in vivo after a single rinse with different mouthwashes.

Material and methods

One mL of unstimulated saliva was collected from volunteers with poor oral hygiene at baseline and 5 min after a 1-min rinsing with diluted Solumium Oral® (hyper-pure 0.0015% chlorine dioxide; ClO₂), Listerine Total Care®, Corsodyl® (0.2% chlorhexidine-digluconate; CHX), or BioGate Si*CLEAN for bacterial investigation. In a second study, volunteers rinsed with 0.003% ClO₂ or CHX for 1 min, and saliva was collected at baseline, after 5 min, and after 90 min. After plating, the total plate and S. mutans colony numbers were determined.

Results

In the first study, ClO₂ and CHX similarly reduced both total germ and S. mutans numbers, while Listerine Total Care® decreased only the S. mutans counts. BioGate Si*Clean had no effect on either the total germ or S. mutans numbers. In the second study, an increasing tendency toward bacterial regrowth was observed with CHX after 90 min compared to the 5-min value, while no change was measured after ClO₂ rinsing.

Conclusion

Hyper-pure ClO₂ rinsing may be a new promising preventive and therapeutic adjuvant in dental practice, as it is similar in effectiveness to the gold standard CHX-containing mouthwashes, especially in patients concerned with taste or tooth discoloration during oral health therapy.

A randomised clinical trial on the effect of oral antimicrobial sprays in institutionalised elders

OBJECTIVE

To compare the effectiveness of chlorine dioxide, chlorhexidine and placebo sprays in improving oral hygiene among institutionalised elders.

BACKGROUND

Available evidence suggests that oral sprays may be an effective alternative delivery method for plaque control; however, few studies have evaluated antimicrobial agents other than chlorhexidine.

MATERIALS AND METHODS

A total of 228 elders across 11 nursing homes in Hong Kong were recruited into the clinical trial. Participants were randomly allocated into one of the following groups: 0.1% pH-balanced chlorine dioxide spray, 0.2% chlorhexidine spray or sterile water spray (placebo control), once daily. Dental plaque, gingival bleeding and other clinical oral health outcomes were assessed at baseline, 3 and 6 months. Participant acceptability of the interventions was assessed at the end of the clinical trial.

RESULTS

Review assessments were conducted for 135 elders at 6 months. Significantly greater reductions in plaque index scores were observed with the chlorhexidine spray (0.4) and chlorine dioxide spray (0.3) than the placebo spray (0.1). While significant reductions in gingival bleeding scores were observed within the chlorhexidine (7.4), chlorine dioxide (7.5) and placebo (5.3) sprays after 6 months, change scores were not significantly different between groups. Significantly greater increases in the levels of staining were observed in the chlorhexidine spray group (-0.1) than the chlorine dioxide (0.0) and placebo spray (0.0) groups.

CONCLUSION

Antimicrobial sprays were shown to be effective among institutionalised elders. Chlorine dioxide spray showed equivalent effects on dental plaque and gingival bleeding relative to the chlorhexidine spray over a 6-month period.

Effects of Chlorine Dioxide on Oral Hygiene - A Systematic Review and Meta-analysis

Background

Effective and selective oral rinses are required in the daily medical and dental practice. Currently mouthwashes used have substantial side effects.

Objectives

Our aim was to evaluate the efficacy of chlorine dioxide-containing mouthwashes in comparison with other previously established mouth rinses in healthy adults using oral hygiene indices.

Methods

This work was registered in PROSPERO (CRD42018099059) and carried out using multiple databases and reported according to the PRISMA statement. The search terms used were “chlorine dioxide” AND “oral”, and only randomised controlled trials (RCTs) were included. The primary outcome was the alteration of the plaque index (PI), while the secondary outcomes were the gingival index (GI) and bacterial counts. For the risk of bias assessment, the Cochrane Risk of Bias Tool was used. Statistical analysis for data heterogeneity was performed by Q-value and I²-tests.

Results

364 articles were found in the databases. After the selection process, only five RCTs were eligible for meta-analysis. Data heterogeneity was low. There were no statistical differences in effectiveness between chlorine dioxide and other effective mouth rinses in PI (0.720±0.119 vs 0.745±0.131; 95%; confidence intervals (CIs): 0.487-0.952 vs 0.489-1.001, respectively) and GI (0.712±0.130 vs 0.745±0.131; 95% CIs: 0.457–0.967 vs 0.489–1.001, respectively) and also in bacterial counts.

Conclusion

Chlorine dioxide reduces both plaque and gingival indices and bacterial counts in the oral cavity similar to other routinely used oral rinses, however, the evidence supporting this outcome is very limited. Therefore, further large scale RCTs are needed to decrease the risk of bias.

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.

Evaluation of the effects of 0.05% sodium hypochlorite and 0.12% chlorhexidine gluconate twice daily rinse on periodontal parameters and gingival crevicular fluid HSV1 and CMV levels in patients with chronic periodontitis: a multicentric study

Background

Mechanical debridement of periodontal pockets remains the mainstay of therapy in all forms of periodontitis. There is 47% greater reduction in plaque amount when sodium hypochlorite (NaOCl) is used as an adjunct when compared with water rinsing. The aim of this study was to evaluate the effects of 0.05% NaOCl and 0.12% chlorhexidine gluconate twice daily rinse on periodontal parameters and gingival crevicular fluid (GCF) HSV1 and CMV levels in chronic periodontitis.

Methods

Patients assigned to group A were prescribed 0.05% NaOCl mouthwash for twice daily rinse. Patients in group B were prescribed 0.12% chlorhexidine gluconate mouthwash to be used twice daily. Evaluation of periodontal parameters was done at baseline and after six months following therapy. GCF HSV1 and CMV levels were evaluated using a polymerase chain reaction.

Results

A statistically significant difference was noted in the improvement in periodontal parameters between both groups, when evaluated six months following therapy with greater reduction in group A vis-a-vis group B.

Conclusion

NaOCl when prescribed as a twice daily mouthwash can be recommended as a part of the home care regime in patients with chronic periodontitis. It is more cost-effective, easily available and can be beneficial to the troops in difficult terrains and extremes of climates, where oral healthcare facilities are not easily accessible.

Evaluation of substantivity of hypochlorous acid as an antiplaque agent: A randomized controlled trial

BACKGROUND

Hypochlorous acid (HOCl) is a non-antibiotic antimicrobial substance with significant effects on pathogenic oral micro-organisms. The effects of HOCl as an antiplaque agent have not been studied.

OBJECTIVE

The aim of this study was to evaluate the substantivity of HOCl mouthwashes compared with chlorhexidine (CHX) rinses and a placebo.

MATERIALS AND METHODS

A double-blind randomized controlled trial with 75 participants was conducted. Participants were divided into five groups using block randomization: 0.025% HOCl, 0.05% HOCl, 0.12% CHX, 0.2% CHX, and sterile water as a placebo. Participants were instructed to use each rinse solution for 30 seconds after dental prophylaxis. Samples of saliva were taken at baseline and after 30 seconds, 1, 3, 5 and 7 hours to assess substantivity, and bacterial viability was established by the fluorescence method. Visible plaque in all participants was assessed with the Turesky index at baseline and at 7 hours, and adverse events were also assessed.

RESULTS

HOCl led to a 33% reduction in bacterial counts in the saliva after 30 seconds compared with a 58% reduction by CHX. HOCl has no substantivity, and bacterial counts returned to baseline after 1 hour. Placebo treatment led to the highest plaque count after 7 hours compared with the CHX and HOCl groups, although the differences were not significant. HOCl rinsing induced the highest percentages of unpleasant taste and dryness sensations.

CONCLUSIONS

HOCl rinses have an initial effect on bacterial viability in saliva but have no substantivity. Other mechanisms may explain its antiplaque effect.

Effect of Aloe vera, chlorine dioxide, and chlorhexidine mouth rinses on plaque and gingivitis: A randomized controlled trial

OBJECTIVE

To evaluate the effect of Aloe vera, chlorine dioxide, and chlorhexidine mouth rinses on plaque and gingivitis in orthodontic treatment.

MATERIALS AND METHODS

A randomized single-center, single-blind, parallel group, controlled trial was conducted among 90 subjects undergoing fixed orthodontic treatment. The subjects were randomly divided into one of the three study groups (Aloe vera, chlorhexidine, chlorine dioxide). Plaque and gingivitis were assessed using modified Silness and Loe Plaque Index and Gingival Index at baseline and at follow-up after 15 days. Paired t-test and ANOVA with post hoc Dunnett test were used. A p-value of <0.05 was considered statistically significant.

RESULTS

A total of 85 participants completed the study; among them, 40 were male and 45 were female. There was significant reduction in mean plaque and gingival scores in all the 3 groups at follow-up when compared to baseline. A significantly higher reduction (plaque and gingival scores) was found in chlorhexidine when compared with the Aloe vera group. However, no significant difference was seen between chlorhexidine and chlorine dioxide with respect to mean reduction in plaque and gingival scores.

CONCLUSION

Chlorine dioxide can be a suitable and economical alternative for chlorhexidine. Further long-term studies are recommended for evaluating their effectiveness.

Inhibition of Tongue Coat and Dental Plaque Formation by Stabilized Chlorine Dioxide Vs Chlorhexidine Mouthrinse: A Randomized, Triple Blinded Study

BACKGROUND

Chlorine dioxide (ClO2) is an oxidizing agent with known bactericidal, viricidal and fungicidal properties. Its efficacy in reducing the halitosis has been established by previous literature. However, data evaluating its antiplaque property is scarce. Chlorhexidine (CHX) is considered as the gold standard and an effective adjunctive to mechanical plaque removal. However, it is associated with few reversible side effects. Therefore a study was conducted to assess the antiplaque property of ClO2 containing mouthrinse against CHX mouthrinse.

AIMS AND OBJECTIVES

To evaluate the efficacy of stabilized chlorine dioxide containing mouthrinse and CHX containing mouthrinse in inhibition of tongue coat accumulation and dental plaque formation using a four day plaque regrowth model clinically and microbiologically in a healthy dental cohort.

MATERIALS AND METHODS

A Single Center, Randomized, Triple blinded, Microbiological clinical trial was conducted involving 25 healthy dental students volunteers (11 males, 14 females). Two commercially available mouthrinse: Mouthrinse A - Aqueous based ClO2 mouthrinse Freshchlor(®) and Mouthrinse B - Aqueous based 0.2% CHX mouthrinse Hexidine(®) were selected as the test products. Subjects were asked to rinse and gargle for 1 minute with the allocated mouthrinse under supervision after supragingival scaling, polishing and tongue coat removal. After four hours, smears were taken from the buccal mucosa and tooth surface. On the fifth day from baseline of four day non brushing plaque regrowth model the samples were again taken from buccal mucosa and tooth surface followed by recording of plaque scores by Rastogi Modification of Navy Plaque index, extent of tongue coat by Winkel's tongue coating index and measuring tongue coat wet weight in grams. The samples collected were subjected to microbial analysis and the results were expressed as colony forming units (CFUs) per sample.

STATISTICAL ANALYSIS

The Data was analysed using SPSS 16.00 and presented using descriptive statistics. Independent t-test was used for the comparison between mouthrinse A groups & mouthrinse B group.

RESULTS

The plaque scores and Winkels tongue coat scores, wet tongue coat weight recorded on the fifth day after the use of the two mouthrinse didn't show a statistically significant difference. The CFU per sample from tooth and mucosa after four hours revealed low bacteria count with respect to mouthrinse B however the CFU obtained on the fifth day did not show a statistically significant difference between the two mouthrinse.

CONCLUSION

The clinical antiplaque efficacy of CHX and ClO2 mouthwash is comparable and so is the efficacy in reducing the oral bacterial load.

Direct effect of chlorine dioxide, zinc chloride and chlorhexidine solution on the gaseous volatile sulfur compounds

OBJECTIVE

This study focused on the ability of aqueous anti-volatile-sulfur-compound (VSC) solutions to eliminate gaseous VSCs by direct contact in a sealed space to describe possible mode of action of anti-VSC agents.

MATERIALS AND METHODS

Twenty milliliters of each experimental solution, 0.16% sodium chlorite, 0.25% zinc chloride, 0.1% chlorhexidine and distilled water, was injected into a Teflon bag containing mixed VSCs, hydrogen sulfide, methyl mercaptan and dimethyl sulfide and mixed vigorously for 30 s. The VSC concentration was measured by gas chromatography before, immediately after, 30 min and 60 min after mixing.

RESULTS

The sodium chlorite solution reduced the VSC concentration remarkably. After mixing, nearly all VSCs were eliminated immediately and no VSCs were detected at 30 and 60 min post-mixing. However, in the other solutions, the VSC concentration decreased by ∼30% immediately after mixing and there was no further decrease.

CONCLUSION

The results suggest that sodium chlorite solution has the effect of eliminating gaseous VSCs directly. This must be because it can release chlorine dioxide gas which can react directly with gaseous VSCs. In the case of other solutions that have been proved to be effective to reduce halitosis clinically, it can be proposed that their anti-VSC effect is less likely due to the direct chemical elimination of gaseous VSCs in the mouth.

Effectiveness of mouthrinses and oral prophylaxis on reduction of microorganisms count in irreversible hydrocolloid impression: an in vivo study

Dental impressions, contaminated with saliva, blood, plaque, are potential source of infection. All impressions should be disinfected after their removal from mouth to prevent cross contamination. Different methods have been tried to disinfect the commonly used irreversible hydrocolloid impression material, but they have been shown to influence the dimensional stability and surface detail of the impression which ultimately affects the precision of the final prosthesis. The aim of this study was to evaluate the efficacy of pre-procedural oral prophylaxis and mouthrinses in reducing the overall microbial load intraorally as well as on alginate impression surface. A total of 60 positive cases selected from 100 subjects who were partially edentulous and above 18 years of age and without medical or pharmacotherapy histories were studied over a period of 18 months, from outpatient clinic of Department of Prosthodontics, GNIDSR. Alginate impressions, before and after prophylaxis were examined microbiologically for the persistence of test microorganisms on the untreated (control group) and the impressions made after treatment. The data were statistically analyzed by the Student t test to assess the effectiveness of the procedure and also the comparative effectiveness of oral prophylaxis and commonly used mouthrinses. The results showed that the impressions were safer when made after oral prophylaxis and/or mouthrinses.

Comparing the efficacy of hyper-pure chlorine-dioxide with other oral antiseptics on oral pathogen microorganisms and biofilm in vitro

This study examines the antibacterial properties of sodium hypochlorite (NaOCl), chlorhexidine gluconate (CHX), Listerine®, and high purity chlorine dioxide (Solumium, ClO2) on selected common oral pathogen microorganisms and on dental biofilm in vitro. Antimicrobial activity of oral antiseptics was compared to the gold standard phenol. We investigated Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis, Veillonella alcalescens, Eikenella corrodens, Actinobacillus actinomycetemcomitans and Candida albicans as some important representatives of the oral pathogens. Furthermore, we collected dental plaque from the upper first molars of healthy young students. Massive biofilm was formed in vitro and its reduction was measured after treating it with mouthrinses: CHX, Listerine® or hyper pure ClO2. Their biofilm disrupting effect was measured after dissolving the crystal violet stain from biofilm by photometer. The results have showed that hyper pure ClO2 solution is more effective than other currently used disinfectants in case of aerobic bacteria and Candida yeast. In case of anaerobes its efficiency is similar to CHX solution. The biofilm dissolving effect of hyper pure ClO2 is significantly stronger compared to CHX and Listerine® after 5 min treatment. In conclusion, hyper pure ClO2 has a potent disinfectant efficacy on oral pathogenic microorganisms and a powerful biofilm dissolving effect compared to the current antiseptics, therefore high purity ClO2 may be a new promising preventive and therapeutic adjuvant in home oral care and in dental or oral surgery practice.

Low-cost periodontal therapy

Periodontitis is a complex infectious disease that affects low-income individuals disproportionately. Periodontitis is associated with specific bacterial species and herpesviruses, and successful prevention and treatment of the disease is contingent upon effective control of these pathogens. This article presents an efficacious, highly safe, minimally invasive, practical and low-cost periodontal therapy that involves professional and patient-administered mechanical therapy and antimicrobial agents. The major components are scaling for calculus removal, periodontal pocket irrigation with potent antiseptics, and treatment with systemic antibiotics for advanced disease. Povidone-iodine and sodium hypochlorite have all the characteristics for becoming the first-choice antiseptics in the management of periodontal diseases. Both agents show excellent antibacterial and antiviral properties, are readily available throughout the world, have been safely used in periodontal therapy for decades, offer significant benefits for individuals with very limited financial resources, and are well accepted by most dental professionals and patients. Four per cent chlorhexidine applied with a toothbrush to the most posterior part to the tongue dorsum can markedly reduce or eliminate halitosis in most individuals. Systemic antibiotics are used to treat periodontopathic bacteria that are not readily reached by topical therapy, such as pathogens within gingival tissue, within furcation defects, at the base of periodontal pockets, and on the tongue, tonsils and buccal mucosae. Valuable antibiotic therapies are amoxicillin-metronidazole (250 mg of amoxicillin and 250 mg of metronidazole, three times daily for 8 days) for young and middle-aged patients, and ciprofloxacin-metronidazole (500 mg of each, twice daily for 8 days) for elderly patients and for patients in developing countries who frequently harbor enteric rods subgingivally. Scaling to remove dental calculus and the prudent use of inexpensive antimicrobial agents can significantly retard or arrest progressive periodontitis in the great majority of patients.

The bactericidal effects of an acidified sodium chlorite-containing oral moisturizing gel: a pilot study

The aim of this study was to examine the bactericidal effects and bactericidal time of an acidified sodium chlorite compound gel (ASC-Gel) on bacteria isolated from the peri-implant sulci of 10 patients who received implants 3-27 years previously, and the depth of each peri-implant sulcus was 5 mm or less. Porphyromonas gingivalis (ATCC33277) was used as the control bacterium. Five ASC-Gel preparations were created by adding 3.3%, 5.0%, 7.0%, 9.0%, and 11.0% citric acid (CA) (condition a, b, c, d, and e, respectively) into an oral moisturizing gel containing sodium chlorite. The concentrations of chlorine dioxide (ClO2) generated in ASC-Gel under conditions (a) to (e) were 12.1, 14.1, 17.2, 21.2, and 39.3 ppm, respectively. We examined the bactericidal effects of the 5 ASC-Gel preparations at volumes of 0.5, 1.0, and 2.0 mL, and measured the bactericidal time when 2.0 mL of ASC-Gel was used under condition (e). The bactericidal effects of ASC-Gel became significantly greater with increased concentrations of CA and ClO2 and with increased usage (0.5-2.0 mL) of the gel. All bacteria were killed by using 2.0 mL of ASC-Gel under condition (e). ASC-Gel also needed between 45 and 90 minutes to kill all microbes under condition (e). Within the limits of the present investigation, these results suggest that ASC-Gel is useful as a chemical disinfectant against bacteria in the peri-implant sulcus. Further studies are also required to protect teeth, the surface of hydroxyapatite-coated implants, and the surrounding soft tissues from effects of chemical dissolution such as acid erosion due to the low pH of ASC-Gel.

Comparing the effects of chlorhexidine and persica on alveolar bone healing following tooth extraction in rats, a randomised controlled trial

Chlorhexidine is broadly prescribed by clinicians for treating extraction socket wounds; however, studies have reported adverse effects for chlorhexidine. Persica, a herbal antibacterial agent, could be an alternative for chlorhexidine. The aim of this randomised controlled trial was to investigate the effects of persica and chlorhexidine on alveolar bone healing following tooth extraction in rats. Eighteen Wistar rats were randomly allocated to three study groups: 0.2% chlorhexidine, 10% persica and controls (tap water). The rats were mouth-rinsed for 14 days. On day 8, the mandibular right first molars of all the rats were extracted. On day 21, the rats were euthanized and histological slides of their extraction sockets were prepared. The amount of new bone formation and the number of inflammatory cells in the extraction socket for each rat were recorded. Data were analysed using linear regression and Mann-Whitney tests. There was no significant difference between the control group and the intervention groups in terms of new bone formation and inflammatory cell count. The mean new bone formation was significantly higher in the persica group than in the chlorhexidine group. There was a significant association between new bone formation and inflammatory cell count in the entire sample. In conclusion, there were no significant differences between rinsing with tap water and rinsing with 0.2% chlorhexidine and 10% persica in enhancing extraction socket wound healing in rats. Extraction socket wound healing in rats was better enhanced with 10% persica than 0.2% chlorhexidine.

Effects of a mouthwash with chlorine dioxide on oral malodor and salivary bacteria: a randomized placebo-controlled 7-day trial

Background

Previous research has shown the oxidizing properties and microbiological efficacies of chlorine dioxide (ClO₂). Its clinical efficacies on oral malodor have been evaluated and reported only in short duration trials, moreover, no clinical studies have investigated its microbiological efficacies on periodontal and malodorous bacteria. Thus, the aim of this study was to assess the inhibitory effects of a mouthwash containing ClO₂ used for 7 days on morning oral malodor and on salivary periodontal and malodorous bacteria.

Methods/Design

A randomized, double blind, crossover, placebo-controlled trial was conducted among 15 healthy male volunteers, who were divided into 2 groups. Subjects were instructed to rinse with the experimental mouthwash containing ClO₂ or the placebo mouthwash, without ClO₂, twice per day for 7 days. After a one week washout period, each group then used the opposite mouthwash for 7 days. At baseline and after 7 days, oral malodor was evaluated with Organoleptic measurement (OM), and analyzed the concentrations of hydrogen sulfide (H₂S), methyl mercaptan (CH₃SH) and dimethyl sulfide ((CH₃)₂S), the main VSCs of human oral malodor, were assessed by gas chromatography (GC). Clinical outcome variables included plaque and gingival indices, and tongue coating index. The samples of saliva were microbiologically investigated. Quantitative and qualitative analyses were performed using the polymerase chain reaction-Invader method.

Results and Discussion

The baseline oral condition in healthy subjects in the 2 groups did not differ significantly. After rinsing with the mouthwash containing ClO₂ for 7 days, morning bad breath decreased as measured by the OM and reduced the concentrations of H₂S, CH₃SH and (CH₃)₂S measured by GC, were found. Moreover ClO₂ mouthwash used over a 7-day period appeared effective in reducing plaque, tongue coating accumulation and the counts of Fusobacterium nucleatum in saliva. Future research is needed to examine long-term effects, as well as effects on periodontal diseases and plaque accumulation in a well-defined sample of halitosis patients and broader population samples.

Trial registration

ClinicalTrials.gov NCT00748943

In vivo substantivity of 0.12% and 0.2% chlorhexidine mouthrinses on salivary bacteria

The in vivo antimicrobial activity of 0.12% and 0.2% chlorhexidine (CHX) on the salivary flora up to 7 h after its application, using epifluorescence microscopy with the SYTO 9/propidium iodide dual staining, was evaluated. Fifteen volunteers performed a single mouthrinse with sterile water (SM-water), a single mouthrinse with 0.12% CHX (0.12% SM-CHX) and a single and double mouthrinse with 0.2% CHX (0.2% SM-CHX and 0.2% DM-CHX). Samples of saliva were taken at 30 s, and 1, 3, 5, and 7 h after each application. In comparison with SM-water, 0.2% CHX (SM and DM) showed a significant antibacterial effect up to 7 h after the mouthrinse, whereas this effect only persisted up to 5 h after the 0.12% SM-CHX mouthrinse. On comparing the two concentrations of CHX, significantly higher percentages of bacterial vitality were observed in all the saliva samples after the use of 0.12% CHX than after 0.2% CHX. On comparison of the 0.2% SM-CHX and 0.2% DM-CHX, significantly higher percentages of live bacteria were observed in the saliva samples taken at 1, 3, 5, and 7 h after the single mouthrinse compared with the double mouthrinse. The 0.2% CHX mouthrinse had the greatest antimicrobial activity on the salivary flora up to 7 h after its application, with a progressive recovery in bacterial vitality. The differences observed with respect to the 0.12% CHX mouthrinse demonstrate the influence of the concentration on its immediate antimicrobial activity and substantivity.

A randomized double blind crossover placebo-controlled clinical trial to assess the effects of a mouthwash containing chlorine dioxide on oral malodor

Background

Previous research has shown the oxidizing properties and microbiological efficacies of chlorine dioxide (ClO₂), however, its clinical efficacies on oral malodor have been evaluated only with organoleptic measurements (OM) or sulphide monitors. No clinical studies have investigated the inhibitory effects of ClO₂ on volatile sulfur compounds (VSCs) using gas chromatography (GC). The aim of this study was to assess the inhibitory effects of a mouthwash containing ClO₂ on morning oral malodor using OM and GC.

Methods

A randomized, double blind, crossover, placebo-controlled clinical trial was conducted among 15 healthy male volunteers, who were divided into 2 groups. In the first test phase, the group 1 subjects (N = 8) were instructed to rinse with the experimental mouthwash containing ClO₂, and those in group 2 (N = 7) to rinse with the placebo mouthwash without ClO₂. In the second test, phase after a one week washout period, each group used the opposite mouthwash.

Oral malodor was evaluated before rinsing, right after rinsing and every 30 minutes up to 4 hours with OM, and concentrations of hydrogen sulfide (H₂S), methyl mercaptan (CH₃SH) and dimethyl sulfide ((CH₃)₂S), the main VSCs of human oral malodor, were evaluated with GC.

Results

The baseline oral condition in the subjects in the 2 groups did not differ significantly. The mouthwash containing ClO₂ improved morning bad breath according to OM and reduced concentrations of H₂S, CH₃SH and (CH₃)₂S according to GC up to 4 hours after rinsing. OM scores with ClO₂ were significantly lower than those without ClO₂ at all examination times. Significant reductions in the concentrations of the three kinds of VSCs measured by GC were also evident at all examination times. The concentrations of the three gases with ClO₂ were significantly lower than those without ClO₂ at most examination times.

Conclusion

In this explorative study, ClO₂ mouthwash was effective at reducing morning malodor for 4 hours when used by healthy subjects.

Trial registration

ClinicalTrials.gov NCT00655772

Chlorine dioxide and chlorhexidine mouthrinses compared in a 3-day plaque accumulation model

BACKGROUND

The aim of this study was to investigate the inhibiting effect of a chlorine dioxide mouthrinse as opposed to a mouthrinse containing chlorhexidine (0.20%) during 3 days of plaque accumulation.

METHODS

At baseline, all participants (N=77) received a professional prophylaxis and were randomly assigned to the test (chlorine dioxide) or (positive) control (chlorhexidine) group. On the following 3 days, both groups rinsed twice daily for 1 minute with 10 ml test or control solution. At the end of the experimental period, plaque was assessed, and the panelists filled out a questionnaire.

RESULTS

Chlorhexidine inhibited plaque growth significantly more than the mouthrinse containing chlorine dioxide (plaque index=1.39 versus 1.96, respectively; P<0.001). The results of the questionnaire showed that the panelists found chlorhexidine easier to use and more effective. However, they preferred the taste of the chlorine dioxide mouthrinse and experienced less taste alterations.

CONCLUSION

Chlorine dioxide mouthrinse seems to be a less potent plaque inhibitor than chlorhexidine.

The effect of a polyhexamethylene biguanide mouthrinse compared with a triclosan rinse and a chlorhexidine rinse on bacterial counts and 4-day plaque re-growth

OBJECTIVES

For various clinical applications, polyhexamethylene biguanide hydrochloride (PHMB) has been used for many years as an antiseptic in medicine. Recently, a 0.04% and a 0.12% PHMB mouthwash were shown to inhibit plaque re-growth and to reduce oral bacterial counts. In this study, a 0.2% PHMB mouthrinse (A) was compared with a positive control 0.12% aqueous chlorhexidine solution (B), a commercially available 0.3% triclosan/2.0% polyvinyl methyl ether maleic acid copolymer mouthrinse (Colgate Total Plax) (C), and a negative control placebo rinse (10% ethanol, flavour) (D).

MATERIALS AND METHODS

The controlled clinical study was a double blind, randomized, four replicate cross - over design. Plaque re-growth was assessed with the Turesky et al. (1970) modification of the Quigley & Hein (1962) plaque index. The antibacterial effect was assessed by taking bacterial counts on the tooth surface (smears from the buccal surface of 16/26) and mucosa (smears from the buccal mucosa in opposite of area 16/26) after the professional prophylaxis and after the first rinse with the preparations on day 1 and prior to the clinical examination on day 5. Sixteen volunteers participated and, on day 1 of each study period were rendered plaque-free, ceased toothcleaning, and rinsed twice daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. A 10-day wash-out period was carried out between each rinse evaluation. Data were analysed using ancova with Bonferroni HSD adjustment for multiple comparisons (colony forming units per sample) with a significance level alpha=0.05.

RESULTS

The 0.2% PHMB mouthrinse (A) was significantly better at inhibiting plaque than the placebo (D), but significant less effective than the 0.12% aqueous chlorhexidine solution (B). There is no significant difference between A and the 0.3% triclosan/2.0% copolymer mouthrinse (C). Bacterial count reductions (tooth surface and mucosa) with PHMB (A) were significantly greater compared with the placebo (D) and triclosan (C), but significantly lower compared with chlorhexidine (B) (tooth surface) and equally effective compared with chlorhexidine (B) (mucosa).

CONCLUSION

Consistent with previous studies, a PHMB mouthrinse was shown to inhibit plaque re-growth and to reduce oral bacterial counts, indicating that PHMB could be an alternative to established mouthrinses in preventive applications.

The role of therapeutic antimicrobial mouthrinses in clinical practice: control of supragingival plaque and gingivitis

BACKGROUND

Although mechanical plaque control methods have the potential to maintain adequate levels of oral hygiene, clinical experience and population-based studies demonstrate that such methods are not being employed sufficiently by large numbers of the population. The need for additional help in controlling bacterial plaque provides the rationale for patients' using antimicrobial mouthrinses as adjuncts to their mechanical oral hygiene regimens.

TYPES OF STUDIES REVIEWED

The author presents an overview of the types of studies used to support the effectiveness of antiplaque and antigingivitis mouthrinses, ranging from laboratory studies to six-month clinical trials. He discusses plaque as an example of a biofilm and the implications of recent research on the nature of biofilms with respect to the nature of the evidence that can be used to demonstrate clinical effectiveness.

CONCLUSIONS

The safety and clinical effectiveness of antiplaque and antigingivitis antimicrobial mouthrinses are best determined using prospective, randomized clinical trials conducted in accordance with ADA guidelines.

CLINICAL IMPLICATIONS

The adjunctive use of antimicrobial mouthrinses can provide significant benefits to patients who cannot maintain adequate levels of plaque and gingivitis control through mechanical methods alone. Dentists should recommend products that have proven clinical activity as demonstrated using generally accepted safety and effectiveness criteria.

A comparison of the plaque-inhibitory properties of stannous fluoride and low-concentration chlorhexidine mouthrinses

BACKGROUND

Plaque inhibition by chlorhexidine (CHX) rinses is dose related with a relatively flat dose-response curve above 5-6 mg twice daily. Low dose regimens could therefore reduce local side effects but maintain reasonable efficacy.

AIMS

To compare the plaque inhibitory properties of two low-dose CHX rinse products with more conventional levels delivered from proprietary rinses. A secondary outcome was a comparison with a stannous fluoride/amine fluoride (SFAF) rinse product.

METHODS

The study was a five-treatments, negative controlled, randomised, single blind crossover design balanced for residual effects, involving 20 healthy subjects in a 24-h plaque re-growth model. On day 1 of each study period, subjects were rendered plaque free, suspended tooth cleaning and followed the appropriate rinse regimen. On day 2, subjects were scored for plaque by index and area. The rinse codes and rinsing regimens were: (A) 15 mg CHX 2 x daily for 30 s (0.1% CHX), (B) 9 mg CHX 2 x daily for 60 s (0.06% CHX), (C) 10 ml SFAF rinse 1 x daily for 30 s, (D) 15 ml placebo 2 x daily for 60 s, and (E) 6 mg CHX 2 x daily for 30 s (0.06% CHX).

RESULTS

Average mouth plaque indices and areas were highly significantly different between rinsing regimens. All test rinses were significantly more effective than the placebo rinse. There was a mean dose-response pattern for the CHX rinses, but there were no statistically significant differences between any of the test rinses.

CONCLUSIONS

Lower doses of chlorhexidine in rinses can be used to exert plaque inhibition comparable with products used at higher doses and equivalent to benchmark products such as the SFAF rinse. However, the availability of chlorhexidine from formulations has to be considered as in part explaining the results.

The effect of a polyhexamethylene biguanide mouthrinse compared to an essential oil rinse and a chlorhexidine rinse on bacterial counts and 4-day plaque regrowth

OBJECTIVES

For various clinical applications, polyhexamethylene biguanide hydrochloride (PHMB) has been used for many years as an antiseptic in medicine. Recently, a 0.04% PHMB mouthwash was shown to inhibit plaque regrowth and to reduce oral bacterial counts. In this study, a 0.12% PHMB mouthrinse (A) was compared with a negative control placebo rinse (10% ethanol, flavour) (B), a positive control 0.12% chlorhexidine rinse (C), and a commercially available mouthrinse containing essential oils (Listerine) (D).

MATERIALS AND METHODS

The study was a double-blind, randomised 4-replicate 4 x 4 Latin square cross-over design in which plaque regrowth was measured. The in vivo antibacterial effect was assessed by taking bacterial counts from the tooth surface and mucosa 4 h after the first rinse with the preparations on day 1 and prior to the clinical examination on day 5. 16 volunteers participated and, on day 1 of each study period, were rendered plaque-free, ceased toothcleaning, and rinsed 2x daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. Washout periods were 9 days. Data were analysed using ANOVA with Bonferroni HSD adjustment for multiple comparisons (significance level alpha=0.05).

RESULTS

The 0.12% PHMB mouthrinse (A) was significantly more effective in inhibiting plaque than the placebo (B) but no significant differences could be observed between A and 0.12% chlorhexidine (C), or between A and Listerine (D). Bacterial count reductions on the tooth surface with PHMB (A) were significantly greater compared to the placebo (B) after 4 h and significantly greater compared to B and D after 5 days. Chlorhexidine (C) was more effective than A after 5 days. On the mucosa, chlorhexidine (C) was significantly more effective in reducing bacterial counts than the other 3 treatments at both time points investigated. PHMB (A) was significantly more effective in reducing bacterial counts than the placebo (B) after 4 h and after 5 days, and than D after 4 h.

CONCLUSION

Consistent with a previous study, a PHMB mouthrinse was shown to inhibit plaque recolonisation and to reduce oral bacterial counts, indicating that PHMB may find applications in the prevention of plaque-associated diseases.

Studies on the effect of polyvinyl pyrrolidone on the activity of chlorhexidine mouthrinses: plaque and stain

BACKGROUND, AIMS

Polyvinyl pyrrolidone (PVP) was shown in vitro to reduce chlorhexidine induced, dietary staining without affecting the uptake of the antiseptic to the test substrate. The aim of these studies in vivo was to determine whether PVP affected plaque and dietary staining by a low concentration chlorhexidine rinse.

METHODS

The plaque and stain studies used a double blind, randomised 6, treatment crossover design involving healthy subjects with a high standard of oral hygiene and gingival health. The rinse formulations under test were: (A) aqueous alcohol (placebo control), (B) 0.03% chlorhexidine, (C) 0.06% chlorhexidine, (D) 0.06% chlorhexidine+1.2% PVP, (E) 0.06% chlorhexidine+5% PVP, (F) 0.06% chlorhexidine+10% PVP. In the plaque study, on day 1 of each period, subjects were rendered plaque free and then rinsed with 15 ml of the test rinse for 60 s. No further tooth cleaning was performed and subjects returned 24 h later for plaque scoring by area. In the stain study, on day 1 of each period, the tongue and teeth of each subject were rendered stain free. Subjects then rinsed under supervision for 60 s with 15 ml of the allocated rinse 8 x a day between 09:00 h and 17:00 h for 3 days. Immediately after each rinse with the test formulation, subjects rinsed for 120 s with 15 ml of warm black tea. Subjects were requested to also drink at least 5 cups of tea or coffee per day. On day 4, stain was scored by area and intensity from designated teeth and dorsum of the tongue. Washout periods were at least 7 days in both studies.

RESULTS

Plaque areas were greatest with placebo and least with 0.06% chlorhexidine. Plaque scores increased with increasing concentrations of PVP in the 0.06% chlorhexidine rinse and were significantly higher than 0.06% chlorhexidine without PVP rinse. Tooth stain areas were comparable for placebo, 0.03% and 0.06% chlorhexidine rinses, but significantly reduced with the PVP/chlorhexidine rinses compared to the 0.06% chlorhexidine rinse. Tooth stain intensity was significantly increased with 0.06% chlorhexidine rinses compared to placebo and chlorhexidine/PVP rinses. Tongue stain area and intensity were significantly reduced with 5% and 10% PVP/chlorhexidine rinses compared to 0.06% chlorhexidine rinse.

CONCLUSION

PVP, at the concentrations tested, reduced the stain propensity of a 0.06% chlorhexidine rinse but at the expense of some loss of plaque inhibition.

The clinical and microbiological effects of a novel acidified sodium chlorite mouthrinse on oral bacterial mucosal infections

Acidified sodium chlorite mouthrinses have been shown to have equivalent anti-plaque activity to those containing chlorhexidine, the current 'gold standard'. In this study, sodium chlorite mouthrinses (ASC) acidified with either malic or gluconic acids were compared to each other and with a chlorhexidine rinse and sterile water for their effect on salivary bacterial counts. Sixteen subjects participated in the study, which had a cross-over Latin square design. In a second study, a sodium chlorite/gluconic acid rinse was compared with chlorhexidine for its clinical and microbiological effects in 36 patients with oral mucosal infections. The sodium chlorite rinses acidified with malic and gluconic acids and the chlorhexidine rinse caused significant reductions in salivary bacterial counts up to 7 h after a single rinse compared with water. There were no significant differences between the three active treatments. In the mucosal infection study, there was a significant reduction in erythema in the chlorhexidine group compared with the ASC group. Patients who received the ASC rinse reported significantly less discomfort following treatment than those receiving the chlorhexidine rinse. Staphylococcus aureus counts were significantly reduced in the group who received the sodium chlorite rinse. There were no other significant differences between the treatments. ASC appears to be an effective alternative to chlorhexidine mouthrinse.

The erosive effects of some mouthrinses on enamel. A study in situ

BACKGROUND

There are both anecdotal clinical and laboratory experimental data suggesting that low pH mouthrinses cause dental erosion. This evidence is particularly relevant to acidified sodium chlorite (ASC) formulations since they have plaque inhibitory properties comparable to chlorhexidine but without the well known local side effects.

AIM

Studies in situ and in vitro were planned to measure enamel erosion by low pH mouthrinses. The study in situ measured enamel erosion by ASC, essential oil and hexetidine mouthrinses over 15-day study periods. The study was a 5 treatment, single blind cross over design involving 15 healthy subjects using orange juice, as a drink, and water, as a rinse, as positive and negative controls respectively. 2 enamel specimens from unerupted human third molar teeth were placed in the palatal area of upper removable acrylic appliances which were worn from 9 a.m. to 5 p.m., Monday to Friday for 3 weeks. Rinses were used 2x daily and 250 ml volumes of orange juice were imbibed 4x daily. Enamel loss was determined by profilometry on days 5, 10 and 15. The study in vitro involved immersing specimens in the 4 test solutions together with a reduced acid ASC formulation for a period of 4 h under constant stirring; Enamel loss was measured by profilometry every hour.

RESULTS

Enamel loss was in situ progressive over time with the 3 rinses and orange juice but negligible with water. ASC produced similar erosion to orange juice and significantly more than the two proprietary rinses and water. The essential oil and hexetidine rinses produced similar erosion and significantly more than water. Enamel loss in vitro was progressive over time, and the order from low to high erosion was reduced acid ASC, ASC, Essential oil, and hexetidine mouthrinses and orange juice.

CONCLUSION

Based on the study in situ, it is recommended that low pH mouthrinses should not be considered for long term or continuous use and never as pre-brushing rinses. In view of the plaque inhibitory efficacy of ASC, short- to medium-term applications similar to those of chlorhexidine would be envisaged.

Topical medications for orofacial neuropathic pain: a review

BACKGROUND

The authors discuss the local pharmacotherapy for chronic orofacial neuropathic pain disorders such as neuropathies, neuromas and neuralgias.

METHODS

The authors conducted a systematic literature review on this topic. The focus of the review involved the two most commonly applied medications for neuropathic disorders--local anesthetics and capsaicin. Other compounds such as nonsteroidal anti-inflammatory drugs, sympathomimetic agents, anticonvulsants and N-methyl-D-aspartate receptor antagonists also were reviewed. The medication delivery and retention methods appropriate for oral and perioral disease and pain control are described in this article.

RESULTS

There are an ever-increasing number of agents that can be used to help patients with neuropathic-based oral and perioral pain problems. Moreover, a clear advancement in the delivery of these medications is the development of a vehicle-carrier agent (pluronic lecithin organogel) that can penetrate the mucosa and cutaneous tissues and carry the active medication with it to the treatment site. The major caveat underlying these treatment strategies is that except for patient testimony and a few studies, there are limited empirical data on the efficacy of most of these new formulations, and additional research is clearly needed.

CONCLUSIONS

Because of their rapid onset and low side-effect profile, topical medications offer a distinct advantage over systemic administration for those orofacial disorders that are regional, near the surface and chronic and that demonstrate some response such as pain relief to topical or subcutaneous anesthetics.

CLINICAL IMPLICATIONS

Practicing dentists now have some new tools they can use to help manage patients who have a chronic nerve pain disorder in and around the mouth.