Is chlorhexidine mouthwash effective in lowering COVID-19 viral load? A systematic review.

OBJECTIVE: This review aims to determine whether there is considerable evidence that mouthwashes containing chlorhexidine (CHX) lower the COVID-19 virus load in saliva. MATERIALS AND METHODS: A comprehensive literature search was carried out in PubMed/Medline, EMBASE, LILACS, Scopus, Web of Science and Cochrane Library, Google Scholar, Open Gray, and ProQuest electronic databases using the keywords: "coronavirus infections" or "coronavirus" or "covid 2019" or "sars 2" or "sars-cov-2" or "sars-cov-19" or "severe acute respiratory syndrome coronavirus 2" or "coronavirus infection" or "severe acute respiratory pneumonia outbreak" and "CHX" or "CHX Hydrochloride" or "CHX Digluconate." A manual search of the articles was also conducted utilizing the reference lists of articles. The in vitro experimental and clinical studies that tested CHX mouthwash were included. Study selection was not restricted or limited to a specific gender, age, ethnicity of individuals, or time of publication. A mix of keywords and proper truncations were used to search for databases. RESULTS: Twelve studies (7 clinical and 5 in vitro) published between 2020 and 2021 were included in this systemic review. Five randomized controlled trials and one clinical case series demonstrated the effectiveness of CHX in reducing the oral viral load; one was inconclusive. Of the five in vitro studies, three showed that CHX is effective against SARS-CoV-2, and two studies denied the effectiveness of CHX. All in vitro studies tested CHX activity concentrations of 0.2, 0.12, and 0.1%. One study reported more than a 99.9% reduction in SARS-CoV-2 viral load in a minimal contact time of 30 seconds. CHX exhibited potent antiviral activity at higher concentrations without cytotoxicity. CONCLUSIONS: Despite differences in the published research, CHX at different concentrations may be effective in lowering the SARS-COV-2 viral load in saliva.

Comparison of the 1 and 2% pilocarpine mouthwash in a xerostomic population: a randomized clinical trial.

AIMS & BACKGROUND: Pilocarpine is an accepted treatment for xerostomia, but limited research has been conducted on the oral, topical form. The present study aimed to compare the effects of 1 and 2% pilocarpine mouthwash on xerostomic participants. METHODS: In this double-blind clinical trial study, 48 subjects with xerostomia were randomly divided into three groups to measure the effects of 1 and 2% pilocarpine and placebo mouthwashes on saliva levels. The amount of saliva in the 1st and 14th days was measured at 0, 45, 60, and 75 mins, while participants used their mouthwash three times a day for 14 days. On the 1st and 14th days, they filled out the information forms on xerostomia and the medicine's side effects before and after the intervention. RESULTS: On the 1st day, the mean salivary flow at 45, 60, and 75 mins in the 2 and 1% pilocarpine mouthwash were significantly higher than in the placebo mouthwash group (p < 0.05). On the 14th day, the mean salivary flow time at 45 mins in the 2% pilocarpine mouthwash group was significantly higher than in the placebo mouthwash group (p = 0.007). Furthermore, the mean salivary flow at 60 and 75 mins in the 2% (p < 0.001) and 1% pilocarpine mouthwash (p = 0.028) was significantly higher than in the placebo group. Moreover, the salivary flow in the 2% pilocarpine mouthwash group was significantly higher than the 1% pilocarpine mouthwash (p < 0.05) during these two times. No side effects were observed in any of the subjects. CONCLUSIONS: The study showed that 5 ml of 2 and 1% pilocarpine mouthwash for 2 weeks increased salivary flow in xerostomic participants compared to placebo without any side effects.

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.

Enjuagues antisépticos bucales como medida de control frente a la trasmisión de SARS-CoV-2 en la atención odontológica.

No disponible.

Strong anti-viral nano biocide based on Ag/ZnO modified by amodiaquine as an antibacterial and antiviral composite.

In this paper, we synthesized Ag/ZnO composite colloidal nanoparticles and the surface of nanoparticles was improved by amodiaquine ligand. The synthesized nanoparticles were characterized using the XRD diffraction pattern, FT-IR Spectroscopy, TEM image, and UV-Vis spectroscopy. The antibacterial, antifungal, and antiviral effects of the synthesized colloid were examined on E.coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Enterococcus hirae bacteria, and Candida Albicans and form spore aspergillus fungi, also influenza, herpes simplex, and covid 19 viruses. The results indicate more than 7 log removal of the bacteria, fungi, and viruses by synthesized colloid with a concentration of 15 µg/L (Ag)/50 µg/ml (ZnO). This removal for covid 19 virus is from 3.2 × 108 numbers to 21 viruses within 30 s. Also, irritation and toxicity tests of the synthesized colloid show harmless effects on human cells and tissues. These colloidal nanoparticles were used as mouthwash solution and their clinical tests were done on 500 people infected by the coronavirus. The results indicate that by washing their mouth and nose three times on day all patients got healthy at different times depending on the depth of the disease. Almost all people with no signs of infection and using this solution as a mouthwash didn't infect by the virus during the study.

SARS-CoV-2-positive patients display considerable differences in proteome diversity in urine, nasopharyngeal, gargle solution and bronchoalveolar lavage fluid samples.

Proteome profile changes post-severe acute respiratory syndrome coronavirus 2 (post-SARS-CoV-2) infection in different body sites of humans remains an active scientific investigation whose solutions stand a chance of providing more information on what constitutes SARS-CoV-2 pathogenesis. While proteomics has been used to understand SARS-CoV-2 pathogenesis, there are limited data about the status of proteome profile in different human body sites infected by the SARS-CoV-2 virus. To bridge this gap, our study aims to characterize the proteins secreted in urine, bronchoalveolar lavage fluid (BALF), gargle solution, and nasopharyngeal samples and assess the proteome differences in these body samples collected from SARS-CoV-2-positive patients. We downloaded publicly available proteomic data from (https://www.ebi.ac.uk/pride/). The data we downloaded had the following identifiers: (i) PXD019423, n = 3 from Charles Tanford Protein Center in Germany. (ii) IPX0002166000, n = 15 from Beijing Proteome Research Centre, China. (iii) IPX0002429000, n = 5 from Huazhong University of Science and Technology, China, and (iv) PXD022889, n = 18 from Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905 USA. MaxQuant was used for the human peptide spectral matching using human and SARS-CoV-2 proteome database which we downloaded from the UniProt database (access date 13th October 2021). The individuals infected with SARS-CoV-2 viruses displayed a different proteome diversity from the different body sites we investigated. Overally, we identified 1809 proteins across the four sample types we compared. Urine and BALF samples had significantly more abundant SARS-CoV-2 proteins than the other body sites we compared. Urine samples had 257(33.7%) unique proteins, followed by nasopharyngeal with 250(32.8%) unique proteins. Gargle solution and BALF had 38(5%) and 73(9.6%) unique proteins respectively. Urine, gargle solution, nasopharyngeal, and bronchoalveolar lavage fluid samples have different protein diversity in individuals infected with SARS-CoV-2. Moreover, our data also demonstrated that a given body site is characterized by a unique set of proteins in SARS-CoV-2 seropositive individuals.

Conservative treatment with mouthwashes followed by tongue photo biomodulation therapy in Covid-19: a case report.

BACKGROUND: Oral manifestations of coronavirus disease 2019 (COVID-19), including ulcers, herpetiform lesions, macules, and petechiae, among others, are becoming increasingly recognized, but there is little guidance on their treatment. Reported cases have described treatment with various mouthwashes containing antivirals, antifungals, antibiotics, anesthetics, or steroids. Our case report is unique in that we provide guidance on the judicious use of these medications, followed by photobiomodulation therapy if the manifestations are treatment resistant. CASE PRESENTATION: We describe a 30-year-old Caucasian woman who tested positive for COVID-19 after developing nasal congestion and cough. Ten days after testing positive, she developed a systemic rash on her extremities and torso. At the same time, she developed swelling of the tongue lasting 1 hour, with subsequent appearance of oral lesions that resembled geographic tongue. She also had an irritable sensation on her tongue and some mild loss of sense of taste. We opted for conservative therapy, including mouth rinses containing lidocaine to be used every 6 hours. The patient used the mouth rinse therapy for 1 month and experienced a 90% improvement in her oral lesions and tongue sensitivity. However, she had repeated flares every 3 weeks over a 6-month period, and the steroid mouthwash achieved incomplete resolution. After three sessions of photobiomodulation therapy, she had no further flares or tongue sensitivity and the lesions healed. CONCLUSIONS: The implication of our report is that we promote the judicious use of topical antibiotics, antivirals, antifungals, and steroids for when they are indicated. We propose lidocaine-containing mouth rinses and steroid mouthwash as an initial, symptomatic treatment regimen for 'COVID-19 tongue.' If there is failure of resolution, we recommend photobiomodulation therapy.

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.

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.

Development and characterisation of cysteine-based gold electrodes for the electrochemical biosensing of the SARS-CoV-2 spike antigen.

This article describes three novel electrochemical biosensing platforms developed to determine the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) spike antigen protein: glutaraldehyde, SARS-CoV-2 spike antibody and bovine serum albumin; N,N-dicyclohexyl carbodiimide/4-(dimethylamino)pyridine functionalised SARS-CoV-2 spike antibody and bovine serum albumin; and 1-ethyl-3-[3-dimethylaminopropyl]-carbodiimide hydrochloride/N-hydroxysuccinimide functionalised SARS-CoV-2 spike antibody and bovine serum albumin modified cysteine-based gold-flower modified glassy carbon electrodes. Two of the produced biosensors having better signals were used to determine the SARS-CoV-2 spike antigen in spiked-saliva and clinical samples containing gargle and mouthwash liquids and characterised using cyclic voltammetry, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The study provides highly significant information in terms of how coupling reagents ought to be used with linkers consisting of both amine and carboxylic acid terminals (i.e. cysteine). The electrochemical cathodic signals based on antibody-antigen protein interactions at approximately -270 mV were evaluated as a response using square wave voltammetry, and they increased in proportion to the SARS-CoV-2 spike antigen. The limit of detection values were 0.93 and 46.3 ag mL-1 in a linear range from 1 ag mL-1 to 100 pg mL-1 and from 100 ag mL-1 to 10 ng mL-1 and the recovery and relative standard deviation values for spiked-saliva samples were 99.50% and 99.40%, and 3.87% and 0.13% for BSA/S-AB/GluAl/Cys/Au/GCE and BSA/S-AB/f-Cys/Au/GCE, respectively. The results showed that both biosensing platforms could be selectively and accurately used to diagnose COVID-19 in RT-PCR-approved clinical samples.

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.

An isothermal lab-on-phone test for easy molecular diagnosis of SARS-CoV-2 near patients and in less than 1 hour.

OBJECTIVES: The performance of a new point-of-care CE-IVD-marked isothermal lab-on-phone COVID-19 assay was assessed in comparison to a gold standard real-time reverse transcriptase-PCR method. METHODS: The study was conducted following a nonprobability sampling of ≥16-year-old volunteers from three different laboratories, using direct mouthwash (N = 24) or nasopharyngeal (N = 191) clinical samples. RESULTS: The assay demonstrated 95.19% sensitivity and 100% specificity for detection of SARS-CoV-2 in direct nasopharyngeal crude samples and 78.95% sensitivity and 100% specificity in direct mouthwash crude samples. It also successfully detected currently predominant SARS-CoV-2 variants of concern (Beta B.1.351, Delta B.1.617.2, and Omicron B.1.1.529) and demonstrated to be inert against potential cross-reactions of other common respiratory pathogens that cause infections that present similar symptoms to COVID-19. CONCLUSION: This lab-on-phone pocket-sized assay relies on an isothermal amplification of SARS-CoV-2's N and E genes, taking just 50 minutes from sample to result, with only 2 minutes of hands-on time. It presents good performance when using direct nasopharyngeal crude samples, enabling a low-cost, real-time, rapid, and accurate identification of SARS-CoV-2 infections at the point of care, which is important for both clinical management and population screening, as a tool to break the chain of transmission of COVID-19 pandemic, especially in low-resources environments.

Antiviral effect of cetylpyridinium chloride in mouthwash on SARS-CoV-2.

Cetylpyridinium chloride (CPC), a quaternary ammonium compound, which is present in mouthwash, is effective against bacteria, fungi, and enveloped viruses. This study was conducted to explore the antiviral effect of CPC on SARS-CoV-2. There are few reports on the effect of CPC against wild-type SARS-CoV-2 at low concentrations such as 0.001%-0.005% (10-50 µg/mL). Interestingly, we found that low concentrations of CPC suppressed the infectivity of human isolated SARS-CoV-2 strains (Wuhan, Alpha, Beta, and Gamma) even in saliva. Furthermore, we demonstrated that CPC shows anti-SARS-CoV-2 effects without disrupting the virus envelope, using sucrose density analysis and electron microscopic examination. In conclusion, this study provided experimental evidence that CPC may inhibit SARS-CoV-2 infection even at lower concentrations.

Effect of oral antiseptics on the viral load of SARS-CoV-2: A randomized controlled trial.

BACKGROUND: In the oral cavity, which plays an important role in the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it is possible to reduce the viral load of SARS-CoV-2 with antiseptics, thereby minimizing the transmission of the virus during dental procedures. OBJECTIVES: The aim of this study was to clinically evaluate the effect of the hypochlorous acid (HClO) and povidone-iodine (PVP-I) solutions on the oral viral load of SARS-CoV-2. MATERIAL AND METHODS: This randomized controlled trial was conducted on 75 patients hospitalized in the COVID-19 ward of a local hospital. All the patients included in the study were within the first 24 h of hospitalization and the first 5 days of coronavirus disease 2019 (COVID-19) symptoms. The viral load of mouthwash samples was measured with the cycle threshold (Ct) value of SARS-CoV-2 through a realtime reverse transcription polymerase chain reaction (RT-PCR). The patients were divided into 3 groups. The effect on the patient's SARS-CoV-2 viral load was investigated after gargling the mouths and throats for 30 s with HClO, PVP-I and isotonic saline. First, a sample was taken after gargling with isotonic saline, then another sample was taken after gargling for 30 s with a particular antiseptic to determine the viral load of SARS-CoV-2. RESULTS: Comparing the before and after mouthwash samples from all 3 groups, there were no statistically significant differences in the Ct values before and after gargling (p > 0.05). However, there were statistically significant differences in the number of negative samples after the use of HClO and PVP-I, which were positive before gargling (p < 0.05). CONCLUSIONS: In the light of the data obtained in this study, there is insufficient evidence that gargling with HClO or PVP-I reduces viral load. Taken together, these findings imply no role for antiseptics in the transmission of SARS-CoV-2 by the aerosol generated during dental procedures, or more generally, SARS-CoV-2 infection control.

The short-term effect of different chlorhexidine forms versus povidone iodine mouth rinse in minimizing the oral SARS-CoV-2 viral load: An open label randomized controlled clinical trial study.

Several investigations evaluated the possibility of different types of mouth wash rinse in minimizing the SARS-CoV-2 load. However, results still controversial. The study aim is to assess the short-term efficiency of several over-the-counter mouth rinses and lozenges in minimizing the salivary viral load for SARS-CoV-2 in patients with confirmed COVID-19 in comparison to saline. This is a randomized controlled clinical trial with 4 arms. The recruited cases were randomized using a simple randomization technique and were assigned to chlorhexidine digluconate mouth rinse (CHX mouth rinse), 2 mg of chlorhexidine digluconate lozenges (CHX lozenges), povidone iodine mouth rinse (PVP-I mouth rinse) or saline as a control group. Saliva were collected from all study subjects by passive drool technique at two time points. First, prior to intervention with mouth rinse or the lozenges, the baseline saliva sample was collected. Second saliva samples were collected immediately after the mouth rinse. Real time PCR was conducted and the value threshold cycle (Ct) for each sample was recorded. Majority of the participants had an education level of high school or less (60%), were married (68.3), males (58.3%), and non-smokers (58.5%). No statistically significant differences between groups at the two times test (P > .05). However, a significant decrease of salivary viral load in all four groups combined (P-value for E genes = .027, and for S genes = .006), and in PVP-I mouth rinse specifically (P = .003 and P = .045, respectively). Povidone iodine mouth rinse showed a potential influence on the reduction of the viral load on a short-term basis. However, longer-term studies of the effect of these products should be conducted.

Significance of chlorine-dioxide-based oral rinses in preventing SARS-CoV-2 cell entry.

OBJECTIVE: This work aims to determine the efficacy of preprocedural oral rinsing with chlorine dioxide solutions to minimize the risk of coronavirus disease 2019 (COVID-19) transmission during high-risk dental procedures. METHODS: The antiviral activity of chlorine-dioxide-based oral rinse (OR) solutions was tested by pre-incubating with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus in a dosage-dependent manner before transducing to human embryonic kidney epithelial (HEK293T-ACE2) cells, which stably expresses ACE-2 receptor. Viral entry was determined by measuring luciferase activity using a luminescence microplate reader. In the cell-to-cell fusion assay, effector Chinese hamster ovary (CHO-K1) cells co-expressing spike glycoprotein of SARS-CoV-2 and T7 RNA polymerase were pre-incubated with the ORs before co-culturing with the target CHO-K1 cells co-expressing human ACE2 receptor and luciferase gene. The luciferase signal was quantified 24 h after mixing the cells. Surface expression of SARS-CoV-2 spike glycoprotein and ACE-2 receptor was confirmed using direct fluorescent imaging and quantitative cell-ELISA. Finally, dosage-dependent cytotoxic effects of ORs were evaluated at two different time points. RESULTS: A dosage-dependent antiviral effect of the ORs was observed against SARS-CoV-2 cell entry and spike glycoprotein mediated cell-to-cell fusion. This demonstrates that ORs can be useful as a preprocedural step to reduce viral infectivity. CONCLUSIONS: Chlorine-dioxide-based ORs have a potential benefit for reducing SARS-CoV-2 entry and spread.

Validation of a noninvasive aMMP-8 point-of-care diagnostic methodology in COVID-19 patients with periodontal disease.

OBJECTIVES: The aim of this study was to validate an active matrix metalloproteinase (MMP-8) point-of-care diagnostic tool in COVID-19 patients with periodontal disease. SUBJECTS, MATERIALS, AND METHODS: Seventy-two COVID-19-positive and 30 COVID-19-negative subjects were enrolled in the study. Demographic data were recorded, periodontal examination carried out, and chairside tests run for evaluating the expression of active MMP-8 (aMMP-8) in the site with maximum periodontal breakdown via gingival crevicular fluid sampling as well as via a mouth rinse-based kit for general disease activity. In COVID-19-positive patients, the kits were run again once the patients turned COVID-19 negative. RESULTS: The overall (n = 102) sensitivity/specificity of the mouthrinse-based kits to detect periodontal disease was 79.41%/36.76% and that of site-specific kits was 64.71%/55.88% while adjusting for age, gender, and smoking status increased the sensitivity and specificity (82.35%/76.47% and 73.53%/88.24, respectively). Receiver operating characteristic (ROC) analysis for the adjusted model revealed very good area under the ROC curve 0.746-0.869 (p < .001) and 0.740-0.872 (p < .001) (the aMMP-8 mouth rinse and site-specific kits, respectively). No statistically significant difference was observed in the distribution of results of aMMP-8 mouth rinse test (p = .302) and aMMP-8 site-specific test (p = .189) once the subjects recovered from COVID-19. CONCLUSIONS: The findings of the present study support the aMMP-8 point-of-care testing (PoCT) kits as screening tools for periodontitis in COVID-19 patients. The overall screening accuracy can be further increased by utilizing adjunctively risk factors of periodontitis. The reported noninvasive, user-friendly, and objective PoCT diagnostic methodology may provide a way of stratifying risk groups, deciding upon referrals, and in the institution of diligent oral hygiene regimens.