Antiviral mouthwashes: possible benefit for COVID-19 with evidence-based approach

A MULTICENTER, RANDOMIZED, OPEN-LABEL, PLACEBO-CONTROLLED CLINICAL TRIAL OF THE EFFECT OF CETYLPYRIDINIUM CHLORIDE (CPC) MOUTHWASH AND ON-DEMAND AQUEOUS CHLORINE DIOXIDE MOUTHWASH ON SARS-COV-2 VIRAL TITER IN PATIENTS WITH MILD COVID-19

OBJECTIVES

The established effect of cetylpyridinium chloride (CPC) mouthwash on SARS-CoV-2 viral titers is unclear. No clinical trial has examined the impact of on-demand aqueous chlorine dioxide mouthwash on SARS-CoV-2 viral titer.

METHODS

In this multicenter, 3-armed, randomized, open-label, placebo-controlled clinical trial involving mildly symptomatic COVID-19 patients, we randomly assigned them to receive 20 mL of 0.05% CPC, 10 mL of 0.01% on-demand aqueous chlorine dioxide, or 20 mL of purified water as a placebo mouthwash in a 1:1:1 ratio. The primary measurement was the SARS-CoV-2 viral titer in saliva, evaluated by a mixed-effects linear regression model.

RESULTS

49 patients received CPC mouthwash (n=16), on-demand aqueous chlorine dioxide mouthwash (n=16), and placebo (n=17) between January 14, 2024, and February 20, 2024. 0.05% CPC mouthwash significantly reduced salivary viral titer at 10 minutes postuse (-0.97 log10 PFU/mL; 95% CI, -1.64 to -0.30; P = .004), while no such effect was observed at 30 minutes (difference vs placebo, -0.26 log10 PFU/mL; 95% CI, -0.92 to 0.40; P = .435) or 60 minutes (difference vs. placebo, -0.05 log10 PFU/mL; 95% CI, -0.68 to 0.58; P = .877). 0.01% on-demand chlorine dioxide mouthwash did not reduce salivary viral titer at 10 minutes, 30 minutes, or 60 minutes compared to placebo.

CONCLUSIONS

10 minutes after using a 0.05% CPC mouthwash, the salivary viral titer of SARS-CoV-2 decreased compared to placebo. 0.01% on-demand aqueous chlorine dioxide mouthwash and placebo had no significant difference in SARS-CoV-2 viral titers.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCT): jRCTs031230566.

The effects of mouth rinsing and gargling with mouthwash containing povidone-iodine and hydrogen peroxide on the cycle threshold value of Severe Acute Respiratory Syndrome Coronavirus 2: A randomized controlled trial of asymptomatic and mildly symptomatic patients

Background

Coronavirus disease 2019 can spread rapidly. Surgery in the oral cavity poses a high risk of transmission of severe acute respiratory syndrome coronavirus 2. The American Dental Association and the Centers for Disease Control and Prevention recommend the use of mouthwash containing 1.5% hydrogen peroxide (H 2O 2) or 0.2% povidone iodine (PI) to reduce the viral load in the upper respiratory tract and decrease the risk of transmission. The aim of the present study was to analyze the effect of mouth rinsing and gargling with mouthwash containing 1% PI, 0.5% PI, 3% H 2O 2, or 1.5% H 2O 2 and water on the cycle threshold (CT) value obtained by real-time reverse transcription polymerase chain reaction (RT-PCR).

Methods

This study is a randomized single blind controlled clinical trial which has been registered in the International Standard Randomized Controlled Trial Number (ISRCTN) registry on the 3 rd February 2022 (Registration number: ISRCTN18356379). In total, 69 subjects recruited from Persahabatan General Hospital who met the inclusion criteria were randomly assigned to one of four treatment groups or the control group. The subjects were instructed to gargle with 15 mL of mouthwash for 30 s in the oral cavity followed by 30 s in the back of the throat, three times per day for 5 days. CT values were collected on postprocedural days 1, 3, and 5.

Results

The results of the Friedman test significantly differed among the groups (n=15). The CT values increased from baseline (day 0) to postprocedural days 1, 3, and 5.

Conclusions

Mouth rinsing and gargling with mouthwash containing 1% PI, 0.5% PI, 3% H 2O 2, or 1.5% H 2O 2 and water increased the CT value.

Proposed Mechanisms for the Relationship between Periodontal Diseases and the Severity of Covid-19: Common Pathogens, Inflammatory Mediators, and Risk Factors

Periodontal disease (PD) is a chronic inflammatory disease with some cytokine involvement, associated with several risk factors such as diabetes, obesity, etc., Corona Virus Disease 2019 (COVID-19), a new viral infection, also appears to be related to cytokine storm and similar risk factors. In this review, we intend to evaluate the possible relationship between PD and COVID-19. For data collection, English literature was searched in databases including PubMed and Google Scholar. The keywords searched were COVID-19, SARS-CoV-2, PD, respiratory Impact of Oral pathogens on respiratory diseases: Epidemiological studies indicated that oral pathogens are related to acute and chronic lung disease, and dental plaque is a likely reservoir for respiratory pathogens. Viral presence in the periodontal pocket: SARS-CoV-2 may be released from infected periodontal cells into periodontal pockets. Common inflammatory mediators: Several studies showed that the serum levels of interleukins (IL)-1, 6, 17, etc., increase in most patients with severe COVID-19. C-reactive protein (CRP) and endothelin 1(ET-1) may also be related to COVID-19 progression, and these mediators also increase in periodontitis. Common risk factors: Due to studies, diabetes mellitus (DM), obesity, aging, and male sex are the most important risk factors common between PDs and COVID-19 and may affect treatment outcomes and prognosis. PD seems to play a significant role in exacerbating COVID-19 and even affects the mortality rate of disease.

The effect of preprocedural mouthrinses against COVID-19 before acid etching on the microleakage of a resin-based sealant in permanent molars: An in vitro experimental study

Aim

To determine whether rinsing with preprocedural mouthrinses against coronavirus disease before acid etching affects resin-based sealant microleakage.

Materials and Methods

A presented in vitro experimental study was performed on 15 extracted permanent third molars. Samples were randomly allocated into five groups: Group 1-distilled water (control); Group 2-1% hydrogen peroxide; Group 3-1.5% hydrogen peroxide; Group 4-0.5% povidone-iodine; and Group 5-1% povidone-iodine. After the teeth were immersed in the assigned mouth rinses for 60 s, they were sealed with Concise™ white sealant. Subsequently, the teeth were thermocycled for 500 cycles, immersed in 2% methylene blue solution for 24 h, and sectioned with two parallel cuts in the buccolingual direction. Sixty surfaces (12 surfaces in each group) were examined for microleakage under a 40× light microscope and scored as described by Zyskind et al. Welch's one-way analysis of variance test and the Games-Howell test were used to analyze the results at a significance level of P < 0.05 for all tests.

Results

The intergroup comparisons indicated that the 0.5% povidone-iodine group and the 1% povidone-iodine group had significantly higher microleakage compared with the control group. The 1% and 1.5% hydrogen peroxide groups demonstrated no significant difference in mean microleakage scores compared with the control group. There was no significant difference between the povidone groups and the hydrogen peroxide groups.

Conclusions

Preprocedural rinsing with 0.5% and 1% povidone-iodine before acid etching caused higher microleakage of resin-based sealant, while hydrogen peroxide rinsing gave comparable microleakage compared with the control group.

A Comparison of the Effects of Chlorhexidine and Sodium Bicarbonate Mouthwashes on COVID-19-Related Symptoms

Background

Some studies have reported that mouthwashes can decrease the viral load in the mouth, but there is not much information about the effectiveness of mouthwashes on coronavirus disease 2019 (COVID-19). This study was conducted to compare the impact of using two types of mouthwash, chlorhexidine and sodium bicarbonate, on COVID-19 symptoms and infection.

Materials and Methods

The present three-group, double-blind clinical trial examined 116 operating room nurses and anesthesia personnel of certain hospitals of Isfahan University of Medical Sciences, Isfahan, Iran. The participants were randomly assigned to three groups: intervention group 1 (chlorhexidine mouthwash), intervention group 2 (sodium bicarbonate mouthwash), and the control group (placebo). Mouthwash was used twice a day (morning and night) for 2 weeks. The participants were monitored in terms of COVID-19-related symptoms for 4 weeks, from the first day of mouthwash use.

Results

Fisher's exact test indicated a significant difference between the chlorhexidine and control groups in terms of the onset of COVID-19-related symptoms (p = 0.02). There was no significant difference in the symptoms of COVID-19 between the groups, but the groups were significantly different in terms of all symptoms at a 4-week interval (p = 0.04). Furthermore, headache was less observed in the chlorhexidine (p = 0.007) and sodium bicarbonate (p = 0.03) groups compared to the control group.

Conclusions

The use of 0.2% chlorhexidine mouthwash can decrease the onset of COVID-19-related symptoms in health-care workers. In addition, this mouthwash can partially reduce the symptoms of this disease in comparison to the control and sodium bicarbonate groups.

Do Disinfectant Solutions during Gargling Reach the Pharynx?

INTRODUCTION

In times of COVID-19, gargling disinfectant is commonly used. Disinfectant solutions seem to decrease the infection's symptoms. For disinfection, several techniques are reported. So far, there are no data about the regions in the upper airways achieved by gargled fluid.

METHODS

Ten healthy volunteers without any dysphagia were investigated with a high-sensitivity flexible endoscopic evaluation of swallowing (hsFEES®) during and after gargling colored water. One volunteer repeated the gargling process in fast and real-time MRI.

RESULTS

In all cases, no color accumulation was detected on the posterior pharyngeal wall, epi- or hypopharynx during gargling. The MRI scans confirmed the results.

CONCLUSIONS

hsFEES® and fast MRI provide an insight into the gargling pattern. Data show that during gargling, the fluid covers the soft tissue in the oral cavity and the anterior part of the soft palate, but not the posterior pharyngeal wall nor the epi- and hypopharynx.

Administration of Clinical COVID-19 Mouthwashing Protocol and Potential Modulation of Pediatric Oral Bacterial Prevalence of Selenomonas noxia: A Pilot Study

Dental office protocols to combat the SARS-CoV-2 (COVID-19) pandemic include mouth washing for an extended 60 s, thereby reducing detectable oral virus. However, it is unclear whether this protocol has any effects on the newly identified periodontal pathogen and obesity-related bacterium often found among pediatric patients, Selenomonas noxia. To determine if the mouthwash protocol has any measurable effect on S. noxia amongst pediatric patients, clinical pediatric saliva samples were obtained from pediatric patients during routine visits for clinical care and treatment. Using an approved protocol, two saliva samples were collected on the same visit before and after chlorhexidine mouthwash (Sample A, Sample B). The third sample (Sample C) was taken at the recall appointment-usually between two and eight weeks later. A total of n = 97 pre-mouthwash samples, and an equal number of matching post-mouthwash samples (n = 97) were collected, with a small number of matching recall samples (n = 36) that were subsequently collected and identified. The demographic composition of the study sample was analyzed using Chi square statistics. Sample DNA from the matching pre-, post-, and recall collections (Sample A, Sample B, and Sample C) was isolated and screened using qPCR and validated primers, which revealed that 11.1% (n = 4/36) from Sample A tested positive for S. noxia with 0% (n = 0/36) of Sample B testing positive and 13.9% (n = 5/36) of the recall (Sample C) testing positive. In addition, comparative analysis of the qPCR cycle threshold data revealed relatively lower expression (quantity) of S. noxia DNA among the recall samples, as determined by two-tailed t-tests (p=0.004). These data and results provide new evidence for the oral prevalence of S. noxia among pediatric patients, while also demonstrating that the COVID-19 protocol of mouth washing prior to clinical treatment for periods extending up to 60 s may be sufficient to reduce the levels of detectable S. noxia-at least temporarily. More research will be needed to determine whether these effects may be limited to the short- or may exhibit more lasting effects in the long-term.

Effects of Chlorhexidine and Povidone-Iodine on the SARS-CoV-2 Load: A Systematic Review and Meta-analysis

The efficacy of mouthwash for reducing the viral load in patients with the novel coronavirus disease 2019 (COVID-19) remains unclear. This systematic review and meta-analysis comprehensively examined the effects of chlorhexidine (CHX) and povidone-iodine (PVP-I) on the viral load in patients with COVID-19. We performed methodological analysis, systematic review, and meta-analysis of included studies using the Comprehensive Meta-analysis Software. PubMed, EMBASE, Cochrane Library, and ProQuest were searched from December 1, 2019, to December 2, 2021. In total, we included 10 studies of 1,339 patients with COVID-19. Compared with the control group, both CHX and PVP-I significantly reduced the number of negative reverse-transcription polymerase chain reaction (RT-PCR) results (p<0.001) among COVID-19 patients. The CHX and PVP-I were effective on reducing the number of negative RT-PCR results in COVID-19 patients. Additional studies using adequate randomization methods and larger samples are warned.

Aerosol in the oral health-care setting: a misty topic

Studies have shown that mouth and respiratory tract microorganisms can be transported in aerosol and spatter. Due to aerosol-generating procedures, there are potentially various infection risks for patients and those working in health care, especially in oral health care. Dental aerosol can contaminate not only the mucous membranes of the oral health-care professional's mouth, respiratory passages, and eyes but also exposed surfaces and materials in the environment. As such, preventing disease transmission within oral health-care offices is important issue. Since the start of the COVID-19 pandemic, an innumerable amount of (mis)information and advice on how to stay safe and prevent the spread of coronavirus has been published. What preventive measures can and have been taken to counteract this, and what have we learned during the pandemic? This review summarizes relevant literature that has addressed the presence and dispersal of aerosol and spatter as a concern in health care. It includes the sources of dental aerosol, their potential health threats, and strategies for controlling and mitigating their impact. It shows that further research is needed to better understand the potential health risks of dental aerosol and to develop effective strategies for mitigating them. CLINICAL RELEVANCE: Using personal protective equipment, high-volume evacuation systems and pre-procedural antimicrobial agents can help to reduce the potential for infection in oral health-care settings and protect the well-being of oral health-care workers and their patients.

Evaluating the effect of gargling with hydrogen peroxide and povidone-iodine on salivary viral load of SARS-CoV-2: A pilot randomized clinical trial

Background and Aim

This study evaluates the salivary viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in hospitalized patients and outpatients before and after gargling with 1% hydrogen peroxide and 0.25% povidone-iodine in comparison with normal saline.

Patients and Methods

This clinical trial was conducted on 120 participants with laboratory-confirmed coronavirus disease 2019 (COVID-19) in two groups: outpatients (n = 60) and hospitalized patients (n = 60). In each group, the patients were randomly divided into three subgroups of 20 based on their given mouthwash for gargling (hydrogen peroxide, povidone-iodine, or normal saline). Two saliva samples were taken from each patient: the first one before gargling and the second one 10 minutes after gargling 10 ml of the respected mouthwashes for 30 seconds. The TaqMan real-time polymerase chain reaction (PCR) amplification of SARS-CoV-2 was used to measure the viral load.

Results

Saliva samples from 46% of patients were positive for coronavirus before gargling the mouthwashes. The percentage of patients with an initial positive saliva sample was significantly higher in the outpatient group (83.3%) than in the hospitalized group (5.4%) (P = 0.01). According to the findings, gargling any mouthwash similar to saline did not reduce the viral load (P > 0.05).

Conclusion

The saliva of COVID-19 patients in the initial stage of the disease was more likely to contain SARS-CoV-2 than the saliva of the hospitalized patients. Gargling hydrogen peroxide or povidone-iodine did not reduce the salivary SARS-CoV-2 viral load.

Reduction of SARS-CoV-2 salivary viral load with pre-procedural mouth rinses: a randomised, controlled, clinical trial

Introduction The purpose of this study was to test the short-term efficacy of four commercial mouthwashes versus water in reducing SARS-CoV-2 viral load in the oral cavity over clinically relevant time points.Methods In total, 32 subjects that were proven SARS-CoV-2-positive via polymerase chain reaction (PCR)-based diagnostic test were recruited and randomised into five parallel arms. Cycle threshold (Ct) values were compared in saliva samples between the groups, as well as within the groups at baseline (pre-rinse), zero hours, one hour and two hours post-rinse, using SARS-CoV-2 reverse transcription-PCR analysis.Results We observed a significant increase in Ct values in saliva samples collected immediately after rinsing with all the four mouthwashes - 0.12% chlorhexidine gluconate, 1.5% hydrogen peroxide, 1% povidone iodine, or Listerine - compared to water. A sustained increase in Ct values for up to two hours was only observed in the Listerine and chlorohexidine gluconate groups. We were not able to sufficiently power this clinical trial, so the results remain notional but encouraging and supportive of findings in other emerging mouthwash studies on COVID-19, warranting additional investigations.Conclusions Our evidence suggests that in a clinical setting, prophylactic rinses with Listerine or chlorhexidine gluconate can potentially reduce SARS-CoV-2 viral load in the oral cavity for up to two hours. While limited in statistical power due to the difficulty in obtaining this data, we advocate for pre-procedural mouthwashing, like handwashing, as an economical and safe additional precaution to help mitigate the transmission of SARS-CoV-2 from a potentially infected patient to providers.

Efectividad de enjuagues bucales contra virus de la familia coronavirus

La aparición del virus Sars-CoV-2 y la enfermedad Covid-19 han provocado un estado de emergencia en el sistema de salud. Teniendo en cuenta el potencial de la saliva como material contaminante, la práctica odontológica fue una de las áreas que se vio afectada debido al uso de instrumentos que pueden esparcir aerosoles y salpicaduras que contienen microorganismos hacia el medio ambiente. Por esta razón, conociendo su potencial en la inactivación de patógenos, se propuso la utilización de enjuagues bucales en la práctica clínica previo a la realización de procedimientos dentales, sin embargo la evidencia no es clara respecto a su efectividad. Objetivo. Establecer el estado de evidencia actual del efecto de los enjuagues bucales sobre los coronavirus que se encuentran en cavidad. Métodos. Se realizó una revisión sistemática siguiendo todos los parámetros descritos en las DirectricesPRISMA basada en información obtenida en los buscadores Science direct, Pubmed y Dentistry and Oral Science Source. Los criterios de selección incluyeron estudios in vivo e in vitro de texto completo que evidenciaron la efectividad del enjuague bucal contra coronavirus. Resultados. Se obtuvieron 90 artículos, de los cuales sólo 12 cumplían con los criterios de inclusión,8 in vitro y 4 in vivo, que fueron sometidos a la evaluación de calidad metodológica utilizando la lista de verificación de evaluación crítica del JBI.  Conclusiones. Los resultados sugieren que la povidona yodada es efectiva para la inactivación del virus Sars-coV-2 en todas sus concentraciones.

USE OF MOUTHWASH AND DENTIFRICE CONTAINING AN ANTIMICROBIAL PHTHALOCYANINE DERIVATIVE FOR THE REDUCTION OF CLINICAL SYMPTOMS OF COVID-19: A RANDOMIZED TRIPLE-BLIND CLINICAL TRIAL

PURPOSE

This clinical trial aimed to evaluate the use of mouthwash and dentifrice containing an antimicrobial phthalocyanine derivative (APD) to reduce the clinical symptoms in patients with COVID-19.

METHODS

This randomized, triple-blind clinical trial enrolled 134 patients aged 18 years or older who underwent COVID-19 testing through the use of nasopharyngeal swab RT-qPCR in a reference center for the diagnosis of COVID-19, had no clinical contraindications to mouthwash and gargle, and had access to cell phones with communication applications. According to the use of a mouthwash and dentifrice containing antimicrobial phthalocyanine derivatives (APD), patients were randomly assigned (1:1) to the APD or non-APD (control) group. All participants were instructed to floss twice a day, brush teeth for 2 minutes 3 times a day, and gargle/rinse (5 mL) for 1 min/3 times a day for 7 days. An online questionnaire was sent to collect data on the clinical symptoms of COVID-19 3 times: T0 (baseline before using the oral hygiene products), T3 (3 days after), and T7 (7 days after). The investigators, patients, and outcome assessors were blinded to group assignment. The Mann-Whitney, Chi-Square, Fisher's exact, and Cochran's tests were used according to the nature of the variables studied, with the level of significance set at P < .05.

RESULTS

No statistically significant difference was found in the prevalence of symptoms between groups at baseline. A statistically significant reduction in clinical symptoms was found in the control group (fatigue, shortness of breath, hoarse voice, sore throat, nasal congestion, and chest pain) and APD group (cough, fatigue, shortness of breath, hyposmia/anosmia, dysgeusia, hoarse voice, sore throat, nasal congestion, chest pain, diarrhea, and irritability/confusion) during the follow-up period. There were statistically significant differences, with a higher prevalence of symptoms in the control group at T3 and T7. Dysgeusia, sore throat, and irritability/confusion were less prevalent in the APD group at T3, and shortness of breath, hyposmia/anosmia, dysgeusia, hoarse voice, sore throat, diarrhea, and irritability/confusion were more prevalent in the control group at T7.

CONCLUSIONS

Based on this methodology, the results demonstrated that the regular use of mouthwash and dentifrice-containing APD had a positive impact on the clinical symptoms, as reported by patients with COVID-19.

Evaluation of Current Evidence on the Use of Oral Antiseptics Against SARS-CoV-2: A Narrative Review

AIMS AND OBJECTIVES

The detection of SARS-COV-2 in the oral cavity has generated endless claims about the efficacy of using oral mouthwashes to reduce viral load. This review aims to assess the current evidence on the use of oral antiseptics against SARS-CoV-2 and to assess the certainty of the evidence according to the GRADE system. The question this study focussed on was what is the efficacy of oral antiseptics against SARS-CoV-2?

MATERIALS AND METHODS

A bibliographic search was performed in Medline databases through PubMed, Science Direct, and Google Scholar (until February 2022), using search terms related to COVID-19 and oral antiseptics. Two independent researchers extracted the information from the articles included in an excel form. The identification and selection of the studies was carried out from August 2021 to February 2022.

RESULTS

It was found that oral antiseptics can have a potential beneficial effect on COVID-19, mainly in reducing viral load. However, these potential benefits are mainly based on in-vitro studies or clinical studies with various methodological limitations. At present, the certainty of the evidence is very low due to inconsistency (heterogeneity), moderate-to-high risk of bias, and imprecision of the results.

CONCLUSION

The certainty of the current evidence on the efficacy of oral antiseptics against SARS-CoV-2 is very low, mainly due to the methodological limitations of the studies. Therefore, for evidence-based decision-making about this intervention, clinical studies with greater methodological rigor are required. Oral antiseptics could present potential benefits in patients with COVID-19 mainly by reducing viral load. However, a careful and conscious evaluation of the evidence is required for decision-making in clinical practice.

Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental healthcare providers

BACKGROUND

Aerosols and spatter are generated in a dental clinic during aerosol-generating procedures (AGPs) that use high-speed hand pieces. Dental healthcare providers can be at increased risk of transmission of diseases such as tuberculosis, measles and severe acute respiratory syndrome (SARS) through droplets on mucosae, inhalation of aerosols or through fomites on mucosae, which harbour micro-organisms. There are ways to mitigate and contain spatter and aerosols that may, in turn, reduce any risk of disease transmission. In addition to personal protective equipment (PPE) and aerosol-reducing devices such as high-volume suction, it has been hypothesised that the use of mouth rinse by patients before dental procedures could reduce the microbial load of aerosols that are generated during dental AGPs.

OBJECTIVES

To assess the effects of preprocedural mouth rinses used in dental clinics to minimise incidence of infection in dental healthcare providers and reduce or neutralise contamination in aerosols.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 4 February 2022.

SELECTION CRITERIA

We included randomised controlled trials and excluded laboratory-based studies. Study participants were dental patients undergoing AGPs. Studies compared any preprocedural mouth rinse used to reduce contaminated aerosols versus placebo, no mouth rinse or another mouth rinse. Our primary outcome was incidence of infection of dental healthcare providers and secondary outcomes were reduction in the level of contamination of the dental operatory environment, cost, change in mouth microbiota, adverse events, and acceptability and feasibility of the intervention.

DATA COLLECTION AND ANALYSIS

Two review authors screened search results, extracted data from included studies, assessed the risk of bias in the studies and judged the certainty of the available evidence. We used mean differences (MDs) and 95% confidence intervals (CIs) as the effect estimate for continuous outcomes, and random-effects meta-analysis to combine data  MAIN RESULTS:  We included 17 studies with 830 participants aged 18 to 70 years. We judged three trials at high risk of bias, two at low risk and 12 at unclear risk of bias.  None of the studies measured our primary outcome of the incidence of infection in dental healthcare providers.  The primary outcome in the studies was reduction in the level of bacterial contamination measured in colony-forming units (CFUs) at distances of less than 2 m (intended to capture larger droplets) and 2 m or more (to capture droplet nuclei from aerosols arising from the participant's oral cavity). It is unclear what size of CFU reduction represents a clinically significant amount. There is low- to very low-certainty evidence that chlorhexidine (CHX) may reduce bacterial contamination, as measured by CFUs, compared with no rinsing or rinsing with water. There were similar results when comparing cetylpyridinium chloride (CPC) with no rinsing and when comparing CPC, essential oils/herbal mouthwashes or boric acid with water. There is very low-certainty evidence that tempered mouth rinses may provide a greater reduction in CFUs than cold mouth rinses. There is low-certainty evidence that CHX may reduce CFUs more than essential oils/herbal mouthwashes. The evidence for other head-to-head comparisons was limited and inconsistent.  The studies did not provide any information on costs, change in micro-organisms in the patient's mouth or adverse events such as temporary discolouration, altered taste, allergic reaction or hypersensitivity. The studies did not assess acceptability of the intervention to patients or feasibility of implementation for dentists.  AUTHORS' CONCLUSIONS: None of the included studies measured the incidence of infection among dental healthcare providers. The studies measured only reduction in level of bacterial contamination in aerosols. None of the studies evaluated viral or fungal contamination. We have only low to very low certainty for all findings. We are unable to draw conclusions regarding whether there is a role for preprocedural mouth rinses in reducing infection risk or the possible superiority of one preprocedural rinse over another. Studies are needed that measure the effect of rinses on infectious disease risk among dental healthcare providers and on contaminated aerosols at larger distances with standardised outcome measurement.

Is hydrogen peroxide an effective mouthwash for reducing the viral load of SARS-CoV-2 in dental clinics?

BACKGROUND

Previous studies have demonstrated that SARS-CoV-2 is mainly transmitted by inhalation of aerosols and can remain viable in the air for hours. Viruses can spread in dental settings and put professionals and patients at high risk of infection due to proximity and aerosol-generating procedures, and poor air ventilation.

OBJECTIVES

The aim of this study was to investigate the effects of a 1% hydrogen peroxide (H2O2) mouth rinse on reducing the intraoral SARS-CoV-2 load.

METHODS

Portable air cleaners with HEPA filters exposed for 3 months were analysed to test for virus presence in a waiting room (where patients wore a face mask but did not undergo mouth rinsing) and three treatment rooms (where patients wore no mask but carried out mouth rinsing). As CO2 is co-exhaled with aerosols containing SARS-CoV-2 by COVID-19 infected people, we also measured CO2 as a proxy of infection risk indoors. Specific primer and probe RT-PCR were applied to detect viral genomes of the SARS-CoV-2 virus in the filters. Specifically, we amplified the nucleocapsid gene (Nuclv) of SARS-CoV-2.

RESULTS

CO2 levels ranged from 860 to 907 ppm, thus indicating low ventilation and the risk of COVID-19 transmission. However, we only found viral load in filters from the waiting room and not from the treatment rooms. The results revealed the efficiency of 1-minute mouth rinsing with 1% H2O2 since patients rinsed their mouths immediately after removing their mask in the treatment rooms.

CONCLUSIONS

Our findings suggest that dental clinics would be safer and more COVID-19 free by implementing mouth rinsing 1 min with 1% H2O2 immediately after the patients arrive at the clinic.

ANTIVIRAL EFFECT OF MOUTHWASHES AGAINST SARS-COV-2: A SYSTEMATIC REVIEW

Objective

This systematic review aimed to evaluate the antiviral effect of mouthwashes against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Material and methods

An electronic search was performed on PubMed, Scopus, Web of Science, Cochrane Library, LILACS, ProQuest, and Google Scholar, and was complemented by a manual search. Both clinical and in vitro studies that focused on the antiviral effect of mouthwashes against SARS-CoV-2 were included. Risk of bias assessment was performed only on the clinical studies using the RoB-2 and ROBINS-I tools.

Results

A total of 907 records were found; after initial selection by title and abstract, 33 full-text articles were selected to be evaluated for eligibility. Finally, a total of 27 studies were included for the qualitative synthesis, including 16 in vitro studies and 11 clinical trials. Antiviral effects were evaluated separately for the in vitro and clinical studies. In vitro studies included mouthwashes containing hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, essential oils, cetylpyridinium chloride, and other compounds; in vivo studies included mouthwashes containing hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, cetylpyridinium chloride, essential oils, chlorine dioxide, β-cyclodextrin-citrox, and sorbitol with xylitol. Povidone-iodine, cetylpyridinium chloride, and essential oils were effective in vitro, while hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, cetylpyridinium chloride, β-cyclodextrin-citrox, and sorbitol with xylitol were effective in vivo. Unclear or high risk of bias was found for almost all clinical studies, and only one study presented with a low risk of bias. No further quantitative analysis was performed.

Conclusion

Although povidone-iodine, cetylpyridinium chloride, and essential oils may be an alternative to reduce the viral load in vitro and in vivo, more studies are needed to determine the real antiviral effect of these different mouthwashes against SARS-CoV-2.

This work was not funded. The protocol was registered in PROSPERO (identification number: CRD42021236134).

Improving safety in dental practices during the COVID-19 pandemic

Coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It originated from the Chinese city of Wuhan and very quickly became a challenging public health problem. On 11 March 2020, the World Health Organization termed this potentially deadly disease a pandemic due to its rapid spread in various parts of the world, giving rise to international health emergencies. This virus is transmitted from human to human in the form of respiratory droplets, and in specific circumstances, airborne transmission may occur. Additional sources of exposure for dentists include blood and infected sharps. Due to the contagious nature of COVID-19 many health care providers have also been disproportionately affected, such as physicians, dentists, nurses, and paramedical staff. Dentists and dental staff are at high risk of cross-infection due to their nature of work. Therefore, they face a dual challenge in protecting themselves and their patients from infection transmission while ensuring that patients receive urgent dental care. In this review, the authors highlight the epidemiology, modes of cross-infection, and recent data on SARS-CoV-2 related to dental practice. The primary purpose is to make dental health care providers aware of the pathophysiology of COVID-19 and to increase their preparedness and understanding of this challenge, which will aid in controlling transmission. The information collected will be useful for the dental community in providing effective patient management through evidence-based recommendations for infection control and disinfection protocols.

1 year impact of COVID-19 pandemic on Italian dental professionals: a cross-sectional survey

BACKGROUND

The Covid-19 pandemic has disrupted the daily work of the dental professionals, assuming unprecedented economic, managerial, and psychological implications. The aim of this cross-sectional survey was to analyze the extent of the impact linked to the imposed working conditions on the Italian dental team.

METHODS

The survey was administered with a web-based form (Google Forms®) to Italian dentists and hygienists. To be enrolled in the study, participants had to reach the adulthood and agree to sign the privacy policy. The impact of Covid-19 was analyzed through a 27-items questionnaire, which was divided into 4 main domains: personal protective equipment (PPE), operative procedures, secretarial organization, and self-reported quality of life (including elearning appraisal).

RESULTS

A total of 614 between dentists and dental hygienists completed the questionnaire. Compared to the pre-pandemic period, the use of PPE such as face shields, surgical caps and disposable gowns were implemented after the Covid-19 outbreak. Almost the whole interviewed (99.9%) received the Covid-19 vaccine. An increased use of preoperatory mouthwashes and rubber dam was referred during the pandemic, while aerosolization (i.e. ultrasound) was drastically reduced. A certain number of respondents (30% dentists, 27% hygienists) suffered from work-related stresses during the pandemic until they desired to change jobs. E-learning was considered beneficial for the 70% of participants.

CONCLUSIONS

Covid-19 pandemic influenced dental professionals' life, leading to a rearrangement of professional, managerial, and cultural life for both dentists and hygienists even after 1 yr from the outbreak.

The effectiveness of mouthwash against SARS-CoV-2 infection: A review of scientific and clinical evidence

BACKGROUND/PURPOSE

The COVID-19 pandemic, caused by the spread of SARS-CoV-2 infection that is mainly through the airborne transmission, is a worldwide health concern. This review seeks to assess the potential effectiveness of mouthwash in reducing the oropharyngeal load of SARS-CoV-2 based on the available evidence.

METHODS

Articles related to mouthwash and COVID-19 in PubMed were electronically searched in July, 2021. After manually excluding articles lacking sufficient scientific evidence or validation processes, those with inaccessible online full text, those that did not test the effectiveness of mouthwash against SARS-CoV-2, and those not written in English, 17 original and 13 review articles were chosen for this review.

RESULTS

The eligible articles revealed that the main virucidal mechanism of mouthwash was via interactions with the viral envelope. Povidone-iodine (PVP-I), cetylpyridinium chloride (CPC), and essential oils with ethanol showed virucidal effects on SARS-CoV-2 in vitro, potentially by interfering with the viral envelope. A few clinical studies demonstrated that PVP-I, CPC, hydrogen peroxide, and chlorhexidine reduced the oropharyngeal load of SARS-CoV-2.

CONCLUSION

Although the available evidence is limited, mouthwash containing PVP-I or CPC shows potential for reducing the oropharyngeal load of SARS-CoV-2 and thus may present a risk-mitigation strategy for COVID-19 patients.

COVID-19 outbreak in North Macedonia: an overview of its impact on dentistry

Since the pandemic of the novel corona virus - SARS-CoV-2 - has been declared and strict social measures have been introduced in the middle of March, including curfew, the dentistry had to adjust and find ways to better adapt itself to the new situation. This article provides a brief overview of the situation with COVID-19 in our country since the beginning of the pandemic, gives a reminder of what COVID-19 is, and which its modes of transmission are, and considers the ways of protection in dental offices taking into account that dentistry is one of the riskiest activities given the patient-dentist proximity and the use of specific high-speed handpieces. This review also provides an overview of the dental preventive measures taken worldwide, including in the field of Pediatric Dentistry, as well as an overview of dental patients' management, and gives possible best ways to care for healthy, sick or patients suspected for COVID-19. Finally, an extensive presentation of the way of work at the University Dental Clinical Center and the Faculty of Dental Medicine in Skopje, North Macedonia, over the last year is given, including protocols for admission of patients.

Salivary SARS-CoV-2 load reduction with mouthwash use: A randomized pilot clinical trial

The saliva of patients with COVID-19 has a high SARS-CoV-2 viral load. The risk of spreading the virus is high, and procedures for viral load reduction in the oral cavity are important. Little research to date has been performed on the effect of mouthwashes on the salivary SARS-CoV-2 viral load. This pilot randomized single-center clinical trial investigated whether three types of mouthwash with solutions containing either 0.075% cetylpyridinium chloride plus 0.28% zinc lactate (CPC + Zn), 1.5% hydrogen peroxide (HP), or 0.12% chlorhexidine gluconate (CHX) reduce the SARS-CoV-2 viral load in saliva at different time points. Sixty SARS-CoV-2-positive patients were recruited and randomly partitioned into a placebo (oral rinsing with distilled water) group and other groups according to the type of mouthwash. Saliva samples were collected from the participants before rinsing (T0), immediately after rinsing (T1), 30 min after rinsing (T2), and 60 min after rinsing (T3). The salivary SARS-CoV-2 viral load was measured by qRT-PCR assays. Rinsing with HP and CPC + Zn resulted in better reductions in viral load, with 15.8 ± 0.08- and 20.4 ± 3.7-fold reductions at T1, respectively. Although the CPC + Zn group maintained a 2.6 ± 0.1-fold reduction at T3, this trend was not observed for HP. HP mouthwash resulted in a significant reduction in the SARS-CoV-2 viral load up to 30 min after rinsing (6.5 ± 3.4). The CHX mouthwash significantly reduced the viral load at T1, T2, and T3 (2.1 ± 1.5-, 6.2 ± 3.8-, and 4.2 ± 2.4-fold reductions, respectively). In conclusion, mouthwash with CPC + Zinc and CHX resulted in significant reductions of the SARS-CoV-2 viral load in saliva up to 60 mins after rinsing, while HP mouthwash resulted in a significant reduction up to 30 mins after rinsing. Despite this transitory effect, these results encourage further studies and suggest that these products could be considered as risk-mitigation strategies for patients infected with SARS-CoV-2.

Dental biofilm of symptomatic COVID-19 patients harbours SARS-CoV-2

Aims

SARS‐CoV‐2 RNA has been recovered from different sites in the human body, including the mouth. The present study aimed to investigate the presence of SARS‐CoV‐2 RNA in the dental biofilm of symptomatic patients who tested positive in nasopharyngeal and oropharyngeal (NASO/ORO) samples.

Materials & Methods

An observational clinical study of individuals with flu‐like symptoms was conducted between July and September 2020. Dental biofilm (BIO) samples were collected and analysed using real‐time quantitative polymerase chain reaction (RT‐qPCR) to determine the virus's presence.

Results

Seventy participants (40 ± 9.8 years of age, 71.4% female) tested positive for SARS‐CoV‐2 RNA in NASO/ORO samples and were included in the study. Among them, 13 tested positive in BIO samples (18.6%; 95% CI: [9.5, 27.7]). The median and interquartile range of cycle quantification (Cq) for NASO/ORO and BIO samples were 15.9 [6.9] and 35.9 [4.0] (p = .001), respectively. BIO‐positive participants showed a higher virus load in NASO/ORO samples (p = .012) than those testing negative (Cq = 20.4 [6.1]).

Conclusions

Dental biofilms from symptomatic COVID‐19 patients harbour SARS‐CoV‐2 RNA and might be a potential reservoir with an essential role in COVID‐19 transmission.

Efficacy of Mouth Rinses Against SARS-CoV-2: A Scoping Review

Introduction:The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in saliva and nasopharyngeal secretions has challenged the routine practice of dentistry. Use of preprocedural mouth rinses has been recommended by several organizations to potentially reduce the transmission of SARS-CoV-2. This scoping review aimed at evaluating the available evidence on the efficacy of mouth rinses against SARS-CoV-2.

Methods:A thorough literature search on electronic databases (PubMed, Scopus, and Google Scholar) was performed by two independent reviewers and data from articles addressing the aim of this article were extracted.

Results:After exclusion of articles not addressing the end point in question, 12 articles were included in this scoping review. Of the 12 articles, seven werein vitrostudies and five werein vivohuman clinical studies. Thein vitrostudies used a standardized methodology (endpoint dilution assay) to evaluate the efficacy of antimicrobial mouth rinses against SARS-CoV-2. Thein vivostudies were done utilizing polymerase chain reaction assay of samples obtained from saliva or nasopharyngeal swab or a combination of both nasopharyngeal and oropharyngeal swab. The reagents tested in these studies included povidone-iodine, chlorhexidine, hydrogen peroxide (H2O2), essential oils, and quaternary ammonium compounds and demonstrated varied efficacy against SARS-CoV-2.

Conclusion:Based on the available evidence fromin vitrostudies, it can be concluded that mouth rinses have a potential to reduce SARS-CoV-2 viral load; however, effectiveness inin vivoconditions is still inconclusive. Owing to the substantial heterogeneity in reporting of the anti–SARS-CoV-2 efficacy of mouth rinses, this review highlights the need to conduct future research with robust and standardized methodologies to confirm effectiveness of mouth rinses.

COVID-19 and Oral Surgery: A narrative review of preoperative mouth rinses

OBJECTIVE

To provide a narrative review of the preprocedural mouth rinse protocols suggested for oral surgery in order to contrast the presence of SARS-CoV-2 in aerosol.

SOURCES AND METHODS

Electronic searches were performed in medical databases PubMed, Medline, CINAHN and Scopus to identify relevant studies published up until the third week of April 2020. This research was supplemented by exploration through a web-based search engine as well as a manual search for international and national guidelines. Studies and protocols which suggested preoperative mouth rinsing as a recommended measure during the COVID-19 outbreak were included. Given the small number of studies, a narrative literature review was conducted. In total, 15 references (11 articles and 4 guidelines) were considered relevant and were critically analysed.

CONCLUSION

The findings show a high heterogeneity in the protocols suggested. Further research is required to better understand the viral features and epidemiologic characteristics of this new virus and to test the efficacy of commonly used antiseptics against SARS-CoV-2 in future clinical trials. However, the use of chlorhexidine, hydrogen peroxide, PVP-I and cetylpyridinium chloride in contrasting the spread of Covid-19 is described as advisable and substantial in different publications.