Estimating salivary carriage of severe acute respiratory syndrome coronavirus 2 in nonsymptomatic people and efficacy of mouthrinse in reducing viral load: A randomized controlled trial

Effectiveness of Preprocedural Mouthwashes: A Triple-Blind Randomised Controlled Clinical Trial

OBJECTIVES

Bioaerosols generated during dental treatment are considered to be potentially carriers of infectious respiratory pathogens. The use of preprocedural mouthwashes has been suggested to reduce microbial load prior to dental surgery procedures. However, limited evidence on the effectiveness of preprocedural mouthwashes regarding mitigating respiratory pathogens exists. The aim of this clinical trial is to determine and compare the effectiveness of 3 preprocedural mouthwashes recommended by the Department of Health of the Hong Kong Special Administrative Region in the mitigation of respiratory pathogens during dental care in pandemic times.

METHODS

In all, 228 participants were block-randomised to three groups based on preprocedural mouthwash used: povidone-iodine, hydrogen peroxide, and chlorhexidine digluconate. Participants, operators, and assessors were blinded to the assigned mouthwashes (triple-blind). Saliva was assessed for the presence of a number of respiratory pathogens (19 viruses including SARS-CoV-2). Changes in the prevalence and mean number of "any" pathogen present following mouthwash use were determined.

RESULTS

Overall, the prevalence of any detected respiratory viral pathogens in the preprocedural saliva was 3.5% as compared to the postprocedural saliva: 1.3% (P = .034). The mean (SD) number of viruses was significantly lower following preprocedural mouthwash use, from 0.04 (0.18) to 0.01 (0.11) (P = .025). No significant differences were observed in the downward change (∆) of any detected virus (prevalence) (P = .155) or in the reduction of the mean number (∆) of any detected virus in the postprocedural saliva compared to preprocedural saliva of participants with respect to mouthwash used (P = .375).

CONCLUSIONS

The practice of using preprocedural mouthwash, as recommended by the government of Hong Kong, was effective in reducing the number of respiratory pathogens present during dental aerosol-generating treatment. This study lends support for official policy on use of preprocedural mouthwashes, which has significant implications for practice and policy during pandemics.

Investigating the effectiveness of commercially available mouthwash on SARS-CoV-2 in vivo using viable virus titre as the primary outcome. A randomised controlled trial

This multi-arm, parallel group, single-blinded randomised controlled trial aimed to assess three commercially available mouthwashes effectiveness against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This manuscript has been written in accordance with the CONSORT statement. Methods. Eligible participants were SARS-CoV-2 positive with a positive test in the last 72 h. All participants had mild to moderate symptoms and could provide five saliva samples over a 60 min period. Participants delivered a baseline saliva sample and then used a mouthwash as per manufacturer's instructions. They provided further saliva samples at minute 1, 10, 30 and 60. Participants were randomised to one of four groups; OraWize+, Total Care Listerine, Cool Mint Listerine and water (control). The lab-based research team were blind to the intervention. The research question was: can SARS-CoV-2 be rendered inactive in saliva by using a mouthwash and how long does this effect last? The primary outcome was the amount of viable infectious SARS-CoV-2 virus in the sample, compared to the baseline sample. The secondary outcome measure was the amount of genetic material from the SARS-CoV-2 virus in the sample, measured via PCR testing. Results. In total 100 participants were recruited (25 per group). Eight participants did not receive the allocated intervention and did not have saliva samples collected. There were no adverse events. In total 42 of the 92 participants had viable virus which could be cultured at baseline. Statistical analysis of the primary outcome was not advised due to the reduced level of viable virus at baseline and the positive skewness present in the distribution of log10(titre) data. Observational data of the primary outcome measure is presented. Analysis of the secondary outcome PCR measure showed that there was strong evidence for a decrease in SARS-CoV-2 RNA levels compared to water for all mouthwashes after 1 min, OraWize+ -0.49 (-0.92, -0.05), p-value 0.029, Cool Mint Listerine -0.81 (-1.25, -0.38), p-value<0.001, Total Care Listerine -1.05 (-1.48, -0.62), p-value<0.001. For the remaining timepoints there was generally no evidence of virus level reduction compared to water although there is weak evidence for a decrease at ten minutes using Total Care Listerine -0.44 (-0.88, 0.01), p-value 0.053. Conclusion. The three mouthwashes included in this trial observationally demonstrated a reduction in virus titre level 1 min after use, with virus levels normalising up to 60 min compared to the control. Although an interesting observation, this result could not be statistically analysed. Using the secondary outcome PCR measure all three included mouthwashes reduced virus levels compared to water at 1 min and these results were statistically significant. Clinically this result does not support the use of the included mouthwashes to reduce SARS-CoV-2 levels in saliva.

Oral mouthwashes for asymptomatic to mildly symptomatic adults with COVID-19 and salivary viral load: a randomized, placebo-controlled, open-label clinical trial

BACKGROUND

Recent randomized clinical trials suggest that the effect of using cetylpyridinium chloride (CPC) mouthwashes on the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load in COVID-19 patients has been inconsistent. Additionally, no clinical study has investigated the effectiveness of on-demand aqueous chlorine dioxide mouthwash against COVID-19.

METHODS

We performed a randomized, placebo-controlled, open-label clinical trial to assess for any effects of using mouthwash on the salivary SARS-CoV-2 viral load among asymptomatic to mildly symptomatic adult COVID-19-positive patients. Patients were randomized to receive either 20 mL of 0.05% CPC, 10 mL of 0.01% on-demand aqueous chlorine dioxide, or 20 mL of placebo mouthwash (purified water) in a 1:1:1 ratio. The primary endpoint was the cycle threshold (Ct) values employed for SARS-CoV-2 salivary viral load estimation. We used linear mixed-effects models to assess for any effect of the mouthwashes on SARS-CoV-2 salivary viral load.

RESULTS

Of a total of 96 eligible participants enrolled from November 7, 2022, to January 19, 2023, 90 were accepted for the primary analysis. The use of 0.05% CPC mouthwash was not shown to be superior to placebo in change from baseline salivary Ct value at 30 min (difference vs. placebo, 0.640; 95% confidence interval [CI], -1.425 to 2.706; P = 0.543); 2 h (difference vs. placebo, 1.158; 95% CI, -0.797 to 3.112; P = 0.246); 4 h (difference vs. placebo, 1.283; 95% CI, -0.719 to 3.285; P = 0.209); 10 h (difference vs. placebo, 0.304; 95% CI, -1.777 to 2.385; P = 0.775); or 24 h (difference vs. placebo, 0.782; 95% CI, -1.195 to 2.759; P = 0.438). The use of 0.01% on-demand aqueous chlorine dioxide mouthwash was also not shown to be superior to placebo in change from baseline salivary Ct value at 30 min (difference vs. placebo, 0.905; 95% CI, -1.079 to 2.888; P = 0.371); 2 h (difference vs. placebo, 0.709; 95% CI, -1.275 to 2.693; P = 0.483); 4 h (difference vs. placebo, 0.220; 95% CI, -1.787 to 2.226; P = 0.830); 10 h (difference vs. placebo, 0.198; 95% CI, -1.901 to 2.296; P = 0.854); or 24 h (difference vs. placebo, 0.784; 95% CI, -1.236 to 2.804; P = 0.447).

CONCLUSIONS

In asymptomatic to mildly symptomatic adults with COVID-19, compared to placebo, the use of 0.05% CPC and 0.01% on-demand aqueous chlorine dioxide mouthwash did not lead to a significant reduction in SARS-CoV-2 salivary viral load. Future studies of the efficacy of CPC and on-demand aqueous chlorine dioxide mouthwash on the viral viability of SARS-CoV-2 should be conducted using different specimen types and in multiple populations and settings.

Efficacy of povidone-iodine nasal rinse and mouth wash in COVID-19 management: a prospective, randomized pilot clinical trial (povidone-iodine in COVID-19 management)

OBJECTIVES/HYPOTHESIS

To assess the efficacy of 0.23% povidone-iodine (PVP-I) nasal rinses and mouth washes on detectability of the coronavirus disease 2019 (COVID-19) virus and cycle threshold (Ct) values in nasopharyngeal swabs.

STUDY DESIGN

This was an open-label, prospective, randomized, placebo-controlled clinical trial.

SETTING

The study was conducted in King Saud University Medical City, Riyadh, Saudi Arabia, from August 2021 to July 2022.

METHODS

Participants diagnosed with SARS-CoV-2 were randomly assigned to one of three groups, with participants receiving either 0.23% PVP-I, 0.9% normal saline (NS) nasal rinses and mouth washes, or no intervention (control group). Nasopharyngeal swabs were taken 4, 8, 12, and 18 days after the first swab to measure the detectability of the virus and the Ct.

RESULTS

A total of 19 participants were involved in this study. The mean viral survival was 9.8, 12, and 12.6 days for the PVP-I, NS, and control groups, respectively, with a statistically significant difference (p = 0.046). The Ct mean values were 23 ± 3.4, 23.5 ± 6.3, and 26.3 ± 5.9 at the time of recruitment and 25.2 ± 3.5, 15 ± 11.7, and 26.9 ± 6.4 after 4 days for the PVP-I, NS, and control groups, respectively.

CONCLUSIONS

When used continuously at a concentration of 0.23%, PVP-I showed promising results in terms of decreasing the pandemic burden by reducing the period of infectiousness and viral load. However, the use of PVP-I did not result in significantly different changes in the quality-of-life parameters in recently vaccinated and mild COVID-19 patients.

Efficacy of different mouthwashes against COVID-19: A systematic review and network meta-analysis

To evaluate the effectiveness of antiseptic mouthwashes in reducing SARS-CoV-2 load clinically and in vitro. A systematic electronic search (MEDLINE/Scopus/Cochrane) was conducted to identify prospective clinical and in vitro studies published between 2019 included and 16 June 2023 assessing the effectiveness of mouthwashes in reducing SARS-CoV-2 load in saliva or surrogates. Data were summarized in tables and a network meta-analysis was performed for clinical trials. Thirty-five studies (14 RCTs, 21 in vitro) fulfilled the inclusion criteria. The risk of bias was judged to be high for 2 clinical and 7 in vitro studies. The most commonly test product was chlorhexidine alone or in combination with other active ingredients, followed by povidone-iodine, hydrogen peroxide and cetylpyridinium chloride. Overall, the descriptive analysis revealed the effectiveness of the mouthwashes in decreasing the salivary viral load both clinically and in vitro. Network meta-analysis demonstrated a high degree of heterogeneity. Among these studies, only chlorhexidine 0.20% was associated to a significant Ct increase in the saliva 5 min after rinsing compared to non-active control (p = 0.027). Data from clinical and in vitro studies suggested the antiviral efficacy of commonly used mouthwashes. Large well-balanced trials are needed to identify the best rinsing protocols.

Mouthwash Effects on the Oral Microbiome: Are They Good, Bad, or Balanced?

This narrative review describes the oral microbiome, and its role in oral health and disease, before considering the impact of commonly used over-the-counter (OTC) mouthwashes on oral bacteria, viruses, bacteriophages, and fungi that make up these microbial communities in different niches of the mouth. Whilst certain mouthwashes have proven antimicrobial actions and clinical effectiveness supported by robust evidence, this review reports more recent metagenomics evidence, suggesting that mouthwashes such as chlorhexidine may cause "dysbiosis," whereby certain species of bacteria are killed, leaving others, sometimes unwanted, to predominate. There is little known about the effects of mouthwashes on fungi and viruses in the context of the oral microbiome (virome) in vivo, despite evidence that they "kill" certain viral pathogens ex vivo. Evidence for mouthwashes, much like antibiotics, is also emerging with regards to antimicrobial resistance, and this should further be considered in the context of their widespread use by clinicians and patients. Therefore, considering the potential of currently available OTC mouthwashes to alter the oral microbiome, this article finally proposes that the ideal mouthwash, whilst combatting oral disease, should "balance" antimicrobial communities, especially those associated with health. Which antimicrobial mouthwash best fits this ideal remains uncertain.

In vivo efficacy of 2% povidone iodine, chlorhexidine gluconate, and herbal extract mouthwash on SARS-CoV-2 viral load in saliva: A randomized clinical trial

Background

One of the major techniques to reduce the transmission rate of COVID-19 would be to decrease the viral titers of SARS-CoV-2 in the saliva of infected patients and it is particularly useful in a dental setting. The present study evaluated the change in salivary viral load of COVID-19 patients using povidone iodine (PI), chlorhexidine (CHX), and an herbal extract (RightSure®) oral antiviral herbal mouthwash (HM) at clinically recommended duration and concentrations.

Materials and Methods

Thirty individuals with SARS-CoV-2 were randomly allocated to three groups: (1) Group 1, PI mouthwash; (2) Group 2, CHX mouthwash; and (3) Group 3, HM mouthwash. A baseline salivary throat sample was collected from all the participants who were later instructed to rinse with their respective mouthwash for 30 s. A second salivary sample was collected 30 min after rinsing. The SARS-CoV-2 viral load was analyzed using real-time reverse-transcription polymerase chain reaction wherein the cyclic threshold (Ct) values were evaluated.

Results

Independent t-test analysis reported a statistically significant difference concerning the PI group (before-after comparison) (P < 0.05). The rest of the two study groups failed to report any significant difference in the nucleocapsid gene and open reading frame 1a gene levels.

Conclusion

While all three types of mouthwash increased the Ct values, a statistically significant difference was observed with PI mouthwash, indicating that it might potentially reduce the spread of the SARS-CoV-2 virus, especially via aerosol but further studies with larger sample size and longer follow-up periods are required to investigate this relationship.

High technology and low technology measures to reduce risk of SARS-CoV-2 transmission

During the coronavirus disease 2019 (COVID-19) pandemic, a variety of low technology and high technology measures have been proposed to reduce the risk for transmission. Identifying those measures likely to be useful in reducing viral transmission without undue expense or potential for adverse effects has been a challenge for infection control programs. The challenge has been compounded by the lack of tools that can be used to assess the risk for viral transmission in different settings. This review discusses practical tools that can be used to assess ventilation and airflow and evaluates some of the low technology and high technology measures that have been proposed as control measures for COVID-19. Some typical questions posed to infection control programs during the pandemic are presented to illustrate real-world application of the concepts being discussed.

Splatter generated by oral surgery irrigation and its implication for infection control

OBJECTIVES

This study aimed to evaluate the splatter contamination generated by rotary instrumentation and irrigation during simulations of surgical extractions. Specifically, comparisons of the splatters generated were made between traditional assistant-based irrigation and self-irrigating drills and between saline and hydrogen peroxide irrigant.

MATERIALS AND METHODS

A fluorescein solution was infiltrated into the irrigation system of high-speed drills, and the surgical extraction procedures were performed on manikins with the typodont teeth. Filter papers were placed at the predetermined locations around the operatory to absorb the fluorescein splatters; these samples underwent photographic image analysis.

RESULTS

The patient chest showed the largest area of splatters, followed by the assistant's face shield. Procedures using the hydrogen peroxide irrigant generated a larger area of splatter than those using the saline irrigant. There was no difference between the splatters produced by assistant irrigation and self-irrigating drill procedures.

CONCLUSIONS

Clinicians should observe and disinfect the locations contaminated by splatters to prevent the spread of infection, since using alternative irrigant or irrigation methods did not reduce the formation of splatters.

CLINICAL RELEVANCE

Oral surgery drills with irrigation generate aerosols and splatters, which have potential to spread airborne pathogens. It is important to understand the patterns of splatters to mitigate contamination.

Effectiveness of mouth rinses against COVID-19: a systematic review and network meta-analysis

OBJECTIVE

This systematic review and network meta-analysis (NMA) comprehensively compared the effectiveness of different mouth rinses in reducing the viral load/infectivity of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) (Part I), alleviating clinical symptoms or severity of disease (Part II), and decreasing the incidence of SARS-CoV-2 infection (Part III).

METHODS

Randomized controlled trials (RCTs) and non-randomized controlled trials (NRCTs) with restrictions were searched up to 3rd March 2023. Twenty-three studies (22 RCTs and one NRCT) met the inclusion criteria for this systematic review.

RESULTS

Five RCTs (454 patients and nine interventions) in Part I were eligible for NMA. The NMA results showed that, in comparison with no rinse, sodium chloride (NaCl) was the most effective mouth rinse for reducing the viral load, followed by povidone-iodine (PVP-I), ß-cyclodextrin + citrox (CDCM), hydrogen peroxide (HP), chlorhexidine gluconate (CHX), cetylpyridinium chloride (CPC), placebo and hypochlorous acid (HClO). However, these results were not significant. Based on surface under the cumulative ranking curve scores, PVP-I was likely to be the most efficacious mouth rinse for reducing SARS-CoV-2 viral load, followed by CDCM, HP, NaCl, CHX, CPC, placebo, no rinse and HClO.

CONCLUSION

Due to heterogeneity of the primary studies, the effectiveness of different mouth rinses to reduce viral infectivity, improve clinical symptoms or prevent SARS-CoV-2 infection remains inconclusive.

Efficacy of three antimicrobial mouthwashes in reducing SARS-CoV-2 viral load in the saliva of hospitalized patients: a randomized controlled pilot study

This study aimed to evaluate the efficacy of 3 mouthwashes in reducing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load in the saliva of coronavirus disease 2019 (COVID-19) patients at 30 min, 1, 2 and 3 h after rinsing. This pilot study included 40 admitted COVID-19 positive patients (10 in each group). Saliva samples were collected before rinsing and at 30 min, 1, 2 and 3 h after rinsing with: Group 1-0.2% Chlorhexidine digluconate (CHX); Group 2-1.5% Hydrogen peroxide (H2O2); Group 3-Cetylpyridinium chloride (CPC) or Group 4 (control group)-No rinsing. Viral load analysis of saliva samples was assessed by Reverse Transcription quantitative PCR. Mean log10 viral load at different time points was compared to that at baseline in all groups using a random effects linear regression analysis while for comparison between groups linear regression analysis was used. The results showed that all groups had a significantly reduced mean log10 viral load both at 2 (p = 0.036) and 3 (p = 0.041) hours compared to baseline. However, there was no difference in mean log10 viral load between any of the investigated mouthwashes and the control group (non-rinsing) at the evaluated time points. Although a reduction in the SARS-CoV-2 viral load in the saliva of COVID-19 patients was observed after rinsing with mouthwashes containing 0.2% CHX, 1.5% H2O2, or CPC, the reduction detected was similar to that achieved by the control group at the investigated time points. The findings of this study may suggest that the mechanical action of rinsing/spitting results in reduction of SARS-CoV-2 salivary load.

Effectiveness of mouthwashes on reducing SARS-CoV-2 viral load in oral cavity: a systematic review and meta-analysis

BACKGROUND

The risk of SARS-COV-2 transmission is relatively high during dental procedures. A study was conducted to investigate the effects of mouthwashes on SARS-COV-2 viral load reduction in the oral cavity.

METHODS

A systematic search was performed in PubMed, EMBASE, Scopus, Web of Science, and Cochrane library for relevant studies up to 20 July, 2022. Randomized and non-randomized clinical trial and quasi-experimental studies evaluating patients with Covid-19 infection (patients) who used mouthwashes (intervention) compared to the same patients before using the mouthwash (comparison) for reducing the SARS-COV-2 load or increasing the cycle threshold (Ct) value (outcome) were searched according to PICO components. Three independent reviewers conducted literature screening and data extraction. The Modified Downs and Black checklist was used for quality assessment. A meta-analysis was performed with a random effects model in the Revman 5.4.1software using the mean difference (MD) of cycle threshold (Ct) values.

RESULTS

Of 1653 articles, 9 with a high methodological quality were included. A meta-analysis indicated that 1% Povidone-iodine (PVP-I) was an effective mouthwash for reducing the SARS-COV-2 viral load [MD 3.61 (95% confidence interval 1.03, 6.19)]. Cetylpyridinium chloride (CPC) [MD 0.61 (95% confidence interval -1.03, 2.25)] and Chlorhexidine gluconate (CHX) [MD -0.04 95% confidence interval (-1.20, 1.12)] were not effective against SARS-COV-2.

CONCLUSION

Using mouthwashes containing PVP-I may be recommended for reducing the SARS-COV-2 viral load in the oral cavity of patients before and during dental procedures, while the evidence is not sufficient for such effects for CPC and CHX-containing mouthwashes.

The anti-SARS-CoV-2 effect and mechanism of Chiehyuan herbal oral protection solution

The Chiehyuan herbal oral protection solution (GB-2) is a herbal mixture commonly utilized in Taiwan for combating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as per traditional Chinese medicine practices. This study assessed the clinical impact of GB-2 through prospective clinical trials. With twice-daily use for a week, GB-2 was shown to diminish the expression of angiotensin-converting enzyme 2 (ACE2) in oral mucosal cells. Moreover, after two weeks of use, it could reduce transmembrane protease, serine 2 (TMRPSS2) expression in these cells. Additionally, in vitro experiments demonstrated that GB-2 lessened the entry efficiency of the Omicron, L452R-D614G, T478K-D614G, and L452R-T478K-D614G variants of the SARS-CoV-2 pseudotyped lentivirus. It also impeded the interaction between ACE2 and the receptor-binding domain (RBD) presenting N501Y-K417N-E484A-G339D-Q493R-G496S-Q498R and L452R-T478K mutations. Glycyrrhizic acid, a major compound in GB-2, also hindered the entry of the Omicron variant (BA.1) of the SARS-CoV-2 pseudotyped lentivirus by obstructing the binding between ACE2 and the RBD presenting the N501Y-K417N-E484A-G339D-Q493R-G496S-Q498R mutation. To sum up, these findings suggest that GB-2 can decrease ACE2 and TMPRSS2 expression in oral mucosal cells. Both glycyrrhizic acid and GB-2 were found to reduce the entry efficiency of the Omicron variant (BA.1) of the SARS-CoV-2 pseudotyped lentivirus and block the binding between ACE2 and the RBD with the N501Y-K417N-E484A-G339D-Q493R-G496S-Q498R mutation. This evidence implies that GB-2 might be a potential candidate for further study as a preventative measure against SARS-CoV-2 infection.

Saline nasal irrigation and gargling in COVID-19: a multidisciplinary review of effects on viral load, mucosal dynamics, and patient outcomes

With unrelenting SARS-CoV-2 variants, additional COVID-19 mitigation strategies are needed. Oral and nasal saline irrigation (SI) is a traditional approach for respiratory infections/diseases. As a multidisciplinary network with expertise/experience with saline, we conducted a narrative review to examine mechanisms of action and clinical outcomes associated with nasal SI, gargling, spray, or nebulization in COVID-19. SI was found to reduce SARS-CoV-2 nasopharyngeal loads and hasten viral clearance. Other mechanisms may involve inhibition of viral replication, bioaerosol reduction, improved mucociliary clearance, modulation of ENaC, and neutrophil responses. Prophylaxis was documented adjunctive to personal protective equipment. COVID-19 patients experienced significant symptom relief, while overall data suggest lower hospitalization risk. We found no harm and hence recommend SI use, as safe, inexpensive, and easy-to-use hygiene measure, complementary to hand washing or mask-wearing. In view of mainly small studies, large well-controlled or surveillance studies can help to further validate the outcomes and to implement its use.

Preprocedural Viral Load Effects of Oral Antiseptics on SARS-CoV-2 in Patients with COVID-19: A Systematic Review

(1) There are limited clinical trials to support the effectiveness of mouth rinses when used as a preprocedural rinse against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This systematic review aims to evaluate the efficacy of antiseptic mouth rinses as a preprocedural rinse in reducing SARS-CoV-2 oral viral load in-vivo. (2) Methods: A literature search was conducted through November 2022 for the following databases: PubMed, Web of Science, Cochrane Library, and Google Scholar. The evaluated outcomes were quantitative changes in viral load and the statistical significance of that change after using antiseptic mouth rinses. (3) Results: 14 randomized controlled trials (RCT) were selected for risk of bias assessment and data extraction. (4) Conclusion: Within the limits of this systematic review, preprocedural mouth rinses may significantly reduce SARS-CoV-2 in the mouth, thus, reducing the viral particles available for airborne dispersion. Preprocedural mouth rinses may be an effective strategy for reducing airborne SARS-CoV-2 dispersion in the environment. Their use may be a preventive strategy to reduce the spread of COVID-19 in selected medical and healthcare facilities, including dental clinics. Potential preprocedural mouth rinses are identified for use as an integral part of safe practice for healthcare protocols. This systematic review was registered with the National Institute for Health Research, international prospective register of systematic reviews (PROSPERO): CRD42022315177.

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.

Preprocedural mouthwashes for infection control in dentistry-an update

OBJECTIVES

Aerosols and splatter are routinely generated in dental practice and can be contaminated by potentially harmful bacteria or viruses such as SARS-CoV-2. Therefore, preprocedural mouthwashes containing antiseptic agents have been proposed as a potential measure for infection control in dental practice. This review article aims to summarize the clinical (and, if insufficient, preclinical) evidence on preprocedural mouthwashes containing antiseptic agents and to draw conclusions for dental practitioners.

METHODS

Literature on preprocedural mouthwashes for reduction of bacterial or viral load in dental aerosols was searched and summarized.

RESULTS

Preprocedural mouthwashes, particularly those containing chlorhexidine digluconate (CHX), cetylpyridinium chloride (CPC), or essential oils (EO), can significantly reduce the bacterial load in dental aerosols. With respect to viruses such as HSV-1, there are too little clinical data to draw any clear recommendations. On the other hand, clinical data is consolidating that CPC-containing mouthwashes can temporarily reduce the intraoral viral load and infectivity in SARS-CoV-2 positive individuals. Nevertheless, potential risks and side effects due to regular antiseptic use such as ecological effects or adaptation of bacteria need to be considered.

CONCLUSIONS

The use of preprocedural mouthwashes containing antiseptics can be recommended according to currently available data, but further studies are needed, particularly on the effects on other viruses besides SARS-CoV-2. When selecting a specific antiseptic, the biggest data basis currently exists for CHX, CPC, EO, or combinations thereof.

CLINICAL RELEVANCE

Preprocedural mouthwashes containing antiseptics can serve as part of a bundle of measures for protection of dental personnel despite some remaining ambiguities and in view of potential risks and side effects.

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.

Efficacy of a Mouthwash Containing CHX and CPC in SARS-CoV-2-Positive Patients: A Randomized Controlled Clinical Trial

Soon after the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, preprocedural mouthwashes were recommended for temporarily reducing intraoral viral load and infectivity of individuals potentially infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in order to protect medical personnel. Particularly, the antiseptic cetylpyridinium chloride (CPC) has shown virucidal effects against SARS-CoV-2 in vitro. Therefore, the aim of this randomized controlled clinical trial was to investigate the efficacy of a commercially available mouthwash containing CPC and chlorhexidine digluconate (CHX) at 0.05% each in SARS-CoV-2-positive patients as compared to a placebo mouthwash. Sixty-one patients who tested positive for SARS-CoV-2 with onset of symptoms within the last 72 h were included in this study. Oropharyngeal specimens were taken at baseline, whereupon patients had to gargle mouth and throat with 20 mL test or placebo (0.9% NaCl) mouthwash for 60 s. After 30 min, further oropharyngeal specimens were collected. Viral load was analyzed by quantitative reverse transcriptase polymerase chain reaction, and infectivity of oropharyngeal specimens was analyzed by virus rescue in cell culture and quantified via determination of tissue culture infectious doses 50% (TCID₅₀). Data were analyzed nonparametrically (α = 0.05). Viral load slightly but significantly decreased upon gargling in the test group (P = 0.0435) but not in the placebo group. Viral infectivity as measured by TCID₅₀ also significantly decreased in the test group (P = 0.0313), whereas there was no significant effect but a trend in the placebo group. Furthermore, it was found that the specimens from patients with a vaccine booster exhibited significantly lower infectivity at baseline as compared to those without vaccine booster (P = 0.0231). This study indicates that a preprocedural mouthwash containing CPC and CHX could slightly but significantly reduce the viral load and infectivity in SARS-CoV-2-positive patients. Further studies are needed to corroborate these results and investigate whether the observed reductions in viral load and infectivity could translate into clinically useful effects in reducing COVID-19 transmission (German Clinical Trials Register DRKS00027812).

Current SARS-CoV-2 Protective Strategies for Healthcare Professionals

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the Coronavirus disease 2019 (COVID-19). COVID-19 was first reported in China in December 2019. SARS-CoV-2 is highly contagious and spread primarily via an airborne route. Hand hygiene, surgical masks, vaccinations and boosters, air filtration, environmental sanitization, instrument sterilization, mouth rinses, and social distancing are essential infection control measures against the transmission of SARS-CoV-2. This paper aims to provide healthcare professionals with evidence-based protective strategies.

Mouth rinses efficacy on salivary SARS-CoV-2 viral load: A randomized clinical trial

Considering the global trend to confine the COVID-19 pandemic by applying various preventive health measures, preprocedural mouth rinsing has been proposed to mitigate the transmission risk of SARS-CoV-2 in dental clinics. The study aimed to investigate the effect of different mouth rinses on salivary viral load in COVID-19 patients. This study was a single-center, randomized, double-blind, six-parallel-group, placebo-controlled clinical trial that investigated the effect of four mouth rinses (1% povidone-iodine, 1.5% hydrogen peroxide, 0.075% cetylpyridinium chloride, and 80 ppm hypochlorous acid) on salivary SARS-CoV-2 viral load relative to the distilled water and no-rinse control groups. The viral load was measured by quantitative reverse transcription PCR (RT-qPCR) at baseline and 5, 30, and 60 min post rinsing. The viral load pattern within each mouth rinse group showed a reduction overtime; however, this reduction was only statistically significant in the hydrogen peroxide group. Further, a significant reduction in the viral load was observed between povidone-iodine, hydrogen peroxide, and cetylpyridinium chloride compared to the no-rinse group at 60 min, indicating their late antiviral potential. Interestingly, a similar statistically significant reduction was also observed in the distilled water control group compared to the no-rinse group at 60 min, proposing mechanical washing of the viral particles through the rinsing procedure. Therefore, results suggest using preprocedural mouth rinses, particularly hydrogen peroxide, as a risk-mitigation step before dental procedures, along with strict adherence to other infection control measures.

Efficacy of mouthrinses in reducing oral SARS-COV-2 load: a review

Accumulated evidence has shown that the oral cavity may be an important reservoir for SARS-CoV-2. Some authors have suggested that the use of mouthrinses could reduce SARS-CoV-2 viral load in the saliva. Thus, the aim of this review was to synthesize evidence about the efficacy of mouthrinses in reducing the salivary viral load of SARS-CoV-2. 2. Nine randomized controlled trials (RCTs) have investigated the efficacy of different mouthrinses in reducing salivary SARS-CoV-2 loads. Various active ingredients have been tested in these trials: 0.5%,1% and 2% povidone-iodine, 0.2% and 0.12% chlorhexidine (CHX), 0.075% cetylpyridinium chloride (CPC), 0.075% CPC with Zinc lactate, 1% and 1.5% hydrogen peroxide (HP), 1.5% HP + 0.12% CHX and ß-cyclodextrin and citrox. The studies reported an intra-group reduction in the salivary levels of the virus, when compared with the baseline. However, the majority of these trials failed to demonstrate a significant inter-group difference between active groups and the control group relative to the decrease in salivary SARS-CoV-2 loads. Although promising, these results should be confirmed by larger trials.

The Oral Cavity Potentially Serving as a Reservoir for SARS-CoV-2 but Not Necessarily Facilitating the Spread of COVID-19 in Dental Practice

Intraoral tissues, secretions, and microenvironments may provide severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with the conditions necessary for viral cellular entry and inhabitation. The aim of the present study is to overview the oral cavity that potentially serves as a reservoir for SARS-CoV-2, and then discuss the possibility that such oral cavity facilitates the spread of coronavirus disease 2019 (COVID-19) in dental practice. Articles were retrieved from PubMed/Medline, LitCovid, ProQuest, Google Scholar, and preprint medRxiv databases. Results of the literature search indicated that SARS-CoV-2 host cell entry-relevant receptor and virus/cell membrane fusion mediators are expressed in major and minor salivary glands, tongue, taste bud, periodontal tissue, and dental pulp, which would be a target and reservoir for SARS-CoV-2. SARS-CoV-2 is present in saliva and gingival crevicular fluid of COVID-19 patients. These secretions would contaminate dental aerosol and droplet with SARS-CoV-2. SARS-CoV-2 inhabits periodontal pocket, gingival sulcus, and dental caries lesion, which could provide SARS-CoV-2 with a habitat. SARS-CoV-2 ribonucleic acid is preserved in dental calculus, which may inform of the previous infection with SARS-CoV-2. Despite involvement of the oral cavity in SARS-CoV-2 transmission and infection, to date, there have been no clusters of COVID-19 in dental practice. Dental settings are much less likely to facilitate the spread of COVID-19 compared with general medical settings, which may be explained by the situation of dentistry that the number of patients to visit dental offices/clinics was decreased during the COVID-19 pandemic, the characteristics of dentistry that dental professionals have maintained high awareness of viral infection prevention, adhered to a strict protocol for infection control, and been using personal protective equipment for a long time, the experimental results that dental devices generate only small amounts of aerosol responsible for the airborne viral transmission, irrigant from the dental unit contributes to the aerosol microbiota much rather than saliva, and the commonly used evacuation or suction system effectively reduces aerosol and droplet generation, and the possibility that human saliva exhibits the antiviral activity and the property to inhibit SARS-CoV-2 infection. It is considered that dental treatment and oral health care can be delivered safely in the COVID-19 era.

The efficacy of mouthwashes in reducing SARS-CoV-2 viral loads in human saliva: A systematic review

This systematic review aimed to evaluate existing randomized controlled trials (RCT) and cohort studies on the efficacy of mouthwashes in reducing SARS-CoV-2 viral loads in human saliva. Searches with pertinent search terms were conducted in PubMed, MEDLINE, Scopus, and Web of Science databases for relevant records published up to Oct 15, 2022. Google Scholar and ProQuest were searched for grey literature. Manual searches were conducted as well for any pertinent articles. The protocol was prospectively registered at PROSPERO (CRD42022324894). Eligible studies were critically appraised for risk of bias and quality of evidence to assess the efficacy of mouthwash in reducing the SARS-CoV-2 viral load in human saliva. Eleven studies were included. The effect on viral load using various types of mouthwash was observed, including chlorhexidine (CHX), povidone-iodine (PI), cetylpyridinium chloride (CPC), hydrogen peroxide (HP), ß-cyclodextrin-citrox mouthwash (CDCM), and Hypochlorous acid (HCIO). Eight articles discussed CHX use. Five were found to be significant and three did not show any significant decrease in viral loads. Eight studies reviewed the use of PI, with five articles identifying a significant decrease in viral load, and three not showing a significant decrease in viral load. HP was reviewed in four studies, two studies identified significant viral load reductions, and two did not. CPC was reviewed in four studies, two of which identified significant viral load reductions, and two did not. CDCM was reviewed in one article which found a significant decrease in viral load reduction. Also, HCIO which was evaluated in one study indicated no significant difference in CT value. The current systematic review indicates that based on these eleven studies, mouthwashes are effective at reducing the SARS-CoV-2 viral load in human saliva. However, further studies should be performed on larger populations with different mouthwashes. The overall quality of evidence was high.

Mouthwashes and the Effect on the Viral Load of SARS-CoV-2 in Saliva: A Literature Review

BACKGROUND: At present, several active ingredients have been investigated in mouthwashes having certain virucidal properties, which could reduce the viral load of SARS-CoV-2 to avoid contamination in medical or dental practice. AIM: The objective of this review is to analyze the available evidence regarding mouthwashes and their effect on the salivary viral load of SARS-CoV-2. METHODS: Records were retrieved from databases such as PubMed, Scopus, Web of Science, and Virtual Health Library up to June 21, 2022. Randomized or non-randomized clinical trials were included where saliva samples and laboratory or in vitro studies were used in the presence of saliva. RESULTS: After a systematic selection process, 11 clinical studies that evaluated at least one mouthwash within clinical protocols and three laboratory studies that evaluated the virucidal efficacy against SARS-CoV-2 in the presence of saliva were finally included. CONCLUSION: There are oral disinfectants with virucidal action in saliva samples, under clinical and laboratory conditions, capable of reducing the viral load of SARS-CoV-2. Cetylpyridinium chloride, chlorhexidine, and povidone-iodine present the best results so far. However, it was also possible to find active principles of recent appearance that, based on favorable exploratory results, needs further investigation on their efficacy and possible adverse events.

Coronavirus outbreaks and infection prevention in dentistry: a narrative review

Objective

This narrative review aims to compile and analyse infection prevention and control (IPAC) practices followed by dental clinics during 3 coronavirus outbreaks: SARS (2002-2004), MERS (2012-2014), and COVID-19 (2019-); and to draw parallels from them for future epidemics.

Methods

Data were collected from 3 databases: Google Scholar, PubMed, and Embase using search terms "SARS," "MERS," "COVID-19," "infection control," "disinfection," and "sterilization".

Results

Careful examination of 108 peer-reviewed articles on the 3 outbreaks revealed the following commonalities in the IPAC practices of dental clinics: use of sodium hypochlorite (surface disinfectant), ethanol and 1-propanol (hand hygiene), povidone-iodine (oral rinse), high-volume evacuation (HVE), rubber dam isolation, anti-retraction handpieces, and fogging.

Discussion & Conclusion

Ethanol, 1-propanol, sodium hypochlorite, povidone-iodine, photocatalysis, and fogging have been shown to be effective against various coronaviruses. However, more studies are required to validate the effectiveness of anti-retraction handpieces, rubber dam isolation, HVE, and cold atmospheric plasma specifically in infection control of the current coronavirus strain, SARS-CoV-2.

Efficacy of Mouth Rinses and Nasal Spray in the Inactivation of SARS-CoV-2: A Systematic Review and Meta-Analysis of In Vitro and In Vivo Studies

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is a global and evolving pandemic associated with heavy health and financial burdens. Considering the oral cavity as the major reservoir for SARS-CoV-2, a systematic review and meta-analysis were conducted to assess the efficacy of mouth rinses and nasal sprays in reducing the salivary viral load of SARS-CoV-2. All in vivo and in vitro studies that assessed the virucidal efficacy of mouth rinses and nasal sprays against SARS-CoV-2 and were published in the English language from December 2019 to April 2022 were considered for analyses. Special Medical Subject Headings terms were used to search Pubmed, Scopus, Embase Ovid, and Web of Science databases. The toxicological data reliability assessment tool (ToxRToool) was used to assess the quality of the included studies. Thirty-three studies (11 in vivo and 22 in vitro) were deemed eligible for inclusion in this analysis. Results of the pooled data showed that povidone-iodine is the most efficacious intervention in vivo in terms of reducing the SARS-CoV-2 salivary viral load, followed by chlorhexidine. The mean difference in the viral load was 86% and 72%, respectively. Similarly, povidone-iodine was associated with the highest log₁₀ reduction value (LRV) in vitro, followed by cetylpyridinium chloride, (LRV = 2.938 (p < 0.0005) and LRV = 2.907 (p = 0.009), respectively). Povidone-iodine-based oral and nasal preparations showed favourable results in terms of reducing SARS-CoV-2 viral loads both in vivo and in vitro. Considering the limited number of patients in vivo, further studies among larger cohorts are recommended.

Oral Antiseptics against SARS-CoV-2: A Literature Review

Dentists are health care workers with the highest risk of exposure to COVID-19, because the oral cavity is considered to be a reservoir for SARS-CoV-2 transmission. The identification of SARS-CoV-2 in saliva, the generation of aerosols, and the proximity to patients during dental procedures are conditions that have led to these health care workers implementing additional disinfection strategies for their protection. Oral antiseptics are widely used chemical substances due to their ability to reduce the number of microorganisms. Although there is still no evidence that they can prevent the transmission of SARS-CoV-2, some preoperative oral antiseptics have been recommended as control measures, by different health institutions worldwide, to reduce the number of microorganisms in aerosols and droplets during dental procedures. Therefore, this review presents the current recommendations for the use of oral antiseptics against SARS-CoV-2 and analyzes the different oral antiseptic options used in dentistry.

Recommendation of the German Society of Hospital Hygiene (DGKH): Prevention of COVID-19 by virucidal gargling and virucidal nasal spray - updated version April 2022

The German Society of Hospital Hygiene develops guidelines, recommendations and standard operation procedures on a voluntary basis, published on the DGKH-website (https://www.krankenhaushygiene.de/). The original German version of this recommendation was published in April 2022 and has now been made available to the international professional public in English. Evaluating the current data on the efficacy of virucidal gargle/mouthwash solutions and nasal sprays against SARS-CoV-2 in vitro and in clinical trials, conducted with preventive or therapeutic objectives, recommendations are given for the prevention of COVID-19. The following areas are considered: Protection of the community when regional clusters or high incidences of infection become knownProtection of the community at low risk of infectionPre-exposure prophylaxis for the protection of healthcare workersPost-exposure prophylaxis.

Efficacy of antiseptic mouthrinses against SARS-CoV-2: A prospective randomized placebo-controlled pilot study

Objectives

Methods

Results

Conclusions

Clinical relevance

Periodontitis and COVID-19: Biological Mechanisms and Meta-analyses of Epidemiological Evidence

Since the beginning of 2020, the entire global health care system has been severely challenged by the outbreak of coronavirus 2019 disease (COVID-19). Robust evidence has demonstrated a more severe course of COVID-19 in the presence of several comorbidities, such as cardiovascular diseases, diabetes mellitus, and obesity. Here, we critically appraise the recent research discoveries linking periodontitis to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to severe COVID-19, with a special focus on the associated biological mechanisms and the available epidemiological evidence. SARS-CoV-2 main receptors and coreceptors (ACE2, TMPRSS2, furin, CD147) are overexpressed in periodontal tissues of periodontitis patients, with inflammation, periodontal pathogens, and damage-induced pyroptosis triggering a positive feedback loop. However, meta-analyses of epidemiological studies only indicated a nonstatistically significant tendency for an increased risk of SARS-CoV-2 infection in subjects with periodontitis (odds ratio [OR] = 1.69; 95% CI, 0.91-3.13, P = 0.09). Furthermore, periodontitis may worsen clinical COVID-19 courses through multiple direct and indirect pathways, including damage to lower airways due to aspiration of periodontal pathogens, exacerbation of the cytokine storm via the low-grade chronic systemic inflammation, and SARS-CoV-2 dissemination through the ulcerated gingival epithelium with consequent induced pulmonary vessels vasculopathy. Indeed, meta-analyses of epidemiological studies indicated that periodontitis subjects are more likely to experience a more severe course of COVID-19. Specifically, periodontitis was associated with a 4-fold increased odds of hospitalization (OR = 4.72; 95% CI, 1.11-20.03, P = 0.04), 6-fold of requiring assisted ventilation (OR = 6.24; 95% CI, 2.78-14.02, P = 0.00), and more than 7-fold of death due to COVID-19 complications (OR = 7.51; 95% CI, 2.16-26.10, P = 0.00). The breakthrough analyzed here emphasizes the relevance of the mouth-systemic connection as a target to mitigate the current COVID-19 emergency and the future predicted coronavirus pandemics.

Efficacy of Combining an Extraoral High-Volume Evacuator with Preprocedural Mouth Rinsing in Reducing Aerosol Contamination Produced by Ultrasonic Scaling

The coronavirus disease pandemic has afforded dental professionals an opportunity to reconsider infection control during treatment. We investigated the efficacy of combining extraoral high-volume evacuators (eHVEs) with preprocedural mouth rinsing in reducing aerosol contamination by ultrasonic scalers. A double-masked, two-group, crossover randomized clinical trial was conducted over eight weeks. A total of 10 healthy subjects were divided into two groups; they received 0.5% povidone-iodine (PI), essential oil (EO), or water as preprocedural rinse. Aerosols produced during ultrasonic scaling were collected from the chest area (PC), dentist's mask, dentist's chest area (DC), bracket table, and assistant's area. Bacterial contamination was assessed using colony counting and adenosine triphosphate assays. With the eHVE 10 cm away from the mouth, bacterial contamination by aerosols was negligible. With the eHVE 20 cm away, more dental aerosols containing bacteria were detected at the DC and PC. Mouth rinsing decreased viable bacterial count by 31-38% (PI) and 22-33% (EO), compared with no rinsing. The eHVE prevents bacterial contamination when close to the patient's mouth. Preprocedural mouth rinsing can reduce bacterial contamination where the eHVE is positioned away from the mouth, depending on the procedure. Combining an eHVE with preprocedural mouth rinsing can reduce bacterial contamination in dental offices.

Perceived Didactic Curricular Effectiveness of In-Person vs. Virtual Formats amongst Fourth-Year Dental Students

Purpose: The COVID-19 pandemic altered the methodologies of dental education delivery, resulting in both immediate and more enduring changes. To assess student perceptions of learning effectiveness, graduating dental students from the class of 2020 were surveyed to identify student comfort with technology and content retention, individual motivation and mental focus, and access to resources pertaining to an abrupt transition to a virtual learning didactic seminar approach in March 2020. Methods: a voluntary, 18-question electronic survey was distributed to fourth-year dental students prior to graduation to assess perceptions of learning outcomes and preferences of a virtual seminar format relative to previous in-person didactic seminars experienced. Results: 34 of 80 dental students (42.5%) completed the electronic survey. Comfort and retention of concepts through virtual learning were reported ≥ by 91% and 85% of the respondents, respectively. Increased distractions and multitasking were reported with virtual learning in 56% and 71%, respectively. Desires to have all teaching conducted through virtual learning platforms was reported at 21%. Conclusions: the positive student responses obtained when comparing virtual to in-person seminars in the survey assessment demonstrates the long-term potential for such delivery modalities to be intentionally incorporated into an evolving predoctoral curriculum in a hybrid nature.

Efficacy of Pre-Procedural Mouthwashes against SARS-CoV-2: A Systematic Review of Randomized Controlled Trials

The oral mucosa is one of the first sites to be affected by the SARS-CoV-2. For this reason, healthcare providers performing aerosol-generating procedures (AGPs) in the oral cavity are at high risk of infection with COVID-19. The aim of this systematic review is to verify whether there is evidence in the literature describing a decrease in the salivary viral load of SARS-CoV-2 after using different mouthwashes. An electronic search of the MEDLINE database (via PubMed), Web of Science, SCOPUS, and the Cochrane library database was carried out. The criteria used were those described by the PRISMA® Statement. Randomized controlled trial studies that have used mouthwashes as a form of intervention to reduce the viral load in saliva were included. The risk of bias was analyzed using the Joanna Briggs Institute Critical Appraisal Tool. Ultimately, eight articles were included that met the established criteria. Based on the evidence currently available in the literature, PVP-I, CHX and CPC present significant virucidal activity against SARS-CoV-2 in saliva and could be used as pre-procedural mouthwashes to reduce the risk of cross-infection.

Virucidal Activity of Different Mouthwashes against the Salivary Load of SARS-CoV-2: A Narrative Review

The saliva of COVID-19-confirmed patients presents a high viral load of the virus. Aerosols generated during medical and dental procedures can transport the virus and are a possible causative agent of cross-infection. Since the onset of the pandemic, numerous investigations have been attempting to mitigate the risk of transmission by reducing the viral load in saliva using preprocedural mouthwashes. This study aims to review the most up-to-date in vitro and in vivo studies investigating the efficacy of different mouthwashes on reducing the salivary viral load of SARS-CoV-2, giving particular attention to the most recent randomized control trials published.

Povidone-Iodine as a Pre-Procedural Mouthwash to Reduce the Salivary Viral Load of SARS-CoV-2: A Systematic Review of Randomized Controlled Trials

The use of pre-procedural rinses has been investigated to reduce the number of viral particles and bacteria in aerosols, potentially decreasing the risk of cross-infection from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during medical and dental procedures. This review aims to confirm whether there is evidence in the literature describing a reduction in salivary load of SARS-CoV-2 when povidone-iodine (PVP-I) is used as a pre-intervention mouthwash. An search of the MEDLINE, Embase, SCOPUS, and the Cochrane library databases was conducted. The criteria used followed the PRISMA® Statement guidelines. Randomized controlled trials investigating the reduction of salivary load of SARS-CoV-2 using PVP-I were included. Ultimately, four articles were included that met the established criteria. According to the current evidence, PVP-I is effective against SARS-CoV-2 in saliva and could be implemented as a rinse before interventions to decrease the risk of cross-infection in healthcare settings.

Cetylpyridinium chloride promotes disaggregation of SARS-CoV-2 virus-like particles

Background

SARS-CoV-2 is continuously disseminating worldwide. The development of strategies to break transmission is mandatory.

Aim of the study

To investigate the potential of cetylpyridinium chloride (CPC) as a viral inhibitor.

Methods

SARS-CoV-2 Virus Like-Particles (VLPs) were incubated with CPC, a potent surfactant routinely included in mouthwash preparations.

Results

Concentrations of 0.05% CPC (w/v) commonly used in mouthwash preparations are sufficient to promote the rupture of SARS-CoV-2 VLP membranes.

Conclusion

Including CPC in mouthwashes could be a prophylactic strategy to keep SARS-CoV-2 from spreading.

Population-based virucidal phthalocyanine gargling/rinsing protocol to reduce the risk of coronavirus disease-2019: a community trial

Aim

In this community trial, the objective was to evaluate the incidence of coronavirus disease-2019 (COVID-19) cases in two similar communities in three distinct phases: 1 (before the intervention), 2 (during the intervention), and 3 (after the intervention).

Methods

The test community received the oral antiseptic intervention (experimental), while the control community did not. The official information agency ("Statewise System for Data Analysis") provided the number of confirmed COVID-19 cases. Data were analyzed according to the three phases per epidemiological week (epi) using the R Core Team (2021) program. The relative risk and 95% confidence intervals between the cumulative incidence values of the test and control communities were calculated for each period. In the test community, a total of 995 residents over 10 years of age received two bottles containing 600 ml of mouthwash containing antiviral phthalocyanine derivative (APD). The participants were asked to gargle/rinse with of 5 mL of the mouthwash containing ADP 3 to 5 times a day, for 1 min, until the bottles were empty.

Results

In phases 1 and 3, the disease risk between the two communities did not differ significantly (p>0.05), while in phase 2, the disease risk was 54% lower in the test community than in the control community.

Conclusion

The use of the APD mouthwash protocol seems to reduce the COVID-19 incidence at the population level, and further studies are needed to confirm its protective effect under more precisely controlled conditions.

Pros and Cons of CAD/CAM Technology for Infection Prevention in Dental Settings during COVID-19 Outbreak

The purpose of this commentary is to update the evidence reported in our previous review on the advantages and limitations of computer-aided design/computer-aided manufacturing technology in the promotion of dental business, as well as to guarantee patient and occupational safety. The COVID-19 pandemic led to an unprecedented focus on infection prevention; however, waves of COVID-19 follow one another, asymptomatic cases are nearly impossible to identify by triage in a dental setting, and the effectiveness of long-lasting immune protection through vaccination remains largely unknown. Different national laws and international guidelines (mainly USA-CDC, ECDC) have often brought about dissimilar awareness and operational choices, and in general, there has been very limited attention to this technology. Here, we discuss its advantages and limitations in light of: (a) presence of SARS-CoV-2 in the oral cavity, saliva, and dental biofilm and activation of dormant microbial infections; (b) the prevention of SARS-CoV-2 transmission by aerosol and fomite contamination; (c) the detection of various oral manifestations of COVID-19; (d) specific information for the reprocessing of the scanner tip and the ward from the manufacturers.

SARS-CoV-2: Overview and Its Impact on Oral Health

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its virulent variants causing coronavirus disease 2019 (COVID-19) COVID-19 has spread rapidly worldwide, and is highly contagious. A comprehensive search was conducted for the most current published information about SARS-CoV-2, COVID-19, and oral health. Clinical studies, case reports, in vivo studies, and any current published evidence on SARS-CoV-2 and COVID-19 were included in this review. Survival against SARS-CoV-2 infection may be partially dependent on periodontal health, good oral hygiene, and access to dental care. Optimum oral health, maintaining good systemic health, and elimination of smoking habits may be beneficial for the prevention and management of COVID-19 infections.

Could mouth rinses be an adjuvant in the treatment of SARS-CoV-2 patients? An appraisal with a systematic review

Objective

A wide variety of mouth rinses are available to combat micro‐organisms in the oral cavity. At the present global pandemic, the need of the hour is to control the viral infection due to the novel corona virus SARS‐COV‐2, as its port of entry is through the receptors located in the oral and pharyngeal mucosa. This systematic literature review focuses on the in vivo studies [randomized control trials (RCTs)] done on the efficacy of existing mouth rinses which have been used in reducing the viral loads.

Methods

The electronic database which includes PubMed‐MEDLINE, Google scholar, Scopus, Web of Science, EMBASE, ProQuest and CINAHL was searched from December 2019 to June 2021 with appropriate Medical Subject Headings (MeSH) terms and Boolean operators. Two reviewers independently reviewed the abstracts.

Results

Of the 2438 retrieved titles, 905 remained after removing duplicates. Twelve articles were eligible to be included in this review of which seven were randomized with adequate sample size.

Conclusions

Mouth washes containing povidone iodine and chlorhexidine decrease the viral load transiently. Large amount of in vivo studies are of paramount importance, especially RCTs, to prove the efficacy of these mouth rinses.