27 February 2026: Clinical Research
Efficacy of Mouthwashes Delivered via Dental Unit Waterlines in Reducing Aerosolized Surrogate SARS-CoV-2
Wendy Wan Yee Hup 
ABCDE 1, Li-Yen Chang ACDE 2, Wen Lin Chai ACDEG 1*
DOI: 10.12659/MSM.950753
Med Sci Monit 2026; 32:e950753
Abstract
BACKGROUND: Preoperative mouthwashes are recommended to reduce viral transmission during aerosol-generating procedures (AGP) in dental settings. However, their effectiveness may be compromised due to dilution by continuous water flow from dental unit waterlines (DUWL). This study evaluated the virucidal efficacy of various mouthwashes when delivered through DUWL using a novel 3D-printed dental aerosol model, with human coronavirus OC43 (hCoV-OC43) as a surrogate for SARS-CoV-2.
MATERIAL AND METHODS: Five mouthwashes – 0.12% chlorhexidine digluconate (CHX), 0.07% cetylpyridinium chloride (CPC), 1% hydrogen peroxide (HP), 0.2% povidone-iodine (PVP-I), and Oral7® – were assessed using suspension and carrier tests at 3 exposure times (30 s, 2 min, and 5 min). Viral infectivity was measured by median tissue culture infectious dose (TCID₅₀/mL), and log reduction values (LRVs) were calculated. The most effective mouthwashes were further evaluated in a novel 3D-printed aerosol model simulating mouthwash delivery through DUWL during AGP.
RESULTS: All tested mouthwashes significantly reduced viral infectivity within 30 s. CPC, PVP-I, and Oral7® achieved >4 log₁₀ reductions (>99.99%) in suspension and aerosol tests. However, only PVP-I and Oral7® appeared to be non-cytotoxic to the host cells.
CONCLUSIONS: PVP-I and Oral7® mouthwashes, when delivered via DUWL, rapidly and effectively reduced aerosolized surrogate SARS-CoV-2 within 30 s in this study, while remaining non-cytotoxic to the host cells. These findings support their potential integration into clinical infection control protocols during AGP.
Keywords: COVID-19, Infection Control, Preventive Dentistry, Printing, Three-Dimensional, Virology
Introduction
During the COVID-19 pandemic, the World Health Organization (WHO) declared aerosol transmission as one of the routes for SARS-CoV-2 viral transmission, especially in poorly ventilated environments with high aerosol generation [1]. In dental practice, procedures involving ultrasonic scalers, high-speed handpieces, and air-water syringes produce significant amounts of bioaerosols, posing a risk to both dental professions and patients [2]. SARS-CoV-2 can remain viable in aerosols for prolonged periods, requiring robust infection control measures in dental settings.
At the onset of the pandemic, preprocedural mouthwash was recommended to reduce the microbial load in the oral cavity, thereby reducing the risk of SARS-CoV-2 transmission [2,3]. Multiple studies suggest that preoperative mouthwash such as povidone-iodine (PVP-I), chlorhexidine (CHX), cetylpyridinium chloride (CPC), and hydrogen peroxide (HP) can significantly reduce the SARS-CoV-2 viral load in vitro and in vivo [4,5]. Clinical studies found that PVP-I, CPC, and HP can reduce salivary viral RNA levels in COVID-19-positive patients, suggesting their potential to decrease viral transmission during aerosol-generating procedures (AGP) [5,6]. However, their effectiveness may be compromised by dilution through continuous water flow during treatment. Furthermore, most studies evaluating mouthwash efficacy have relied on suspension or carrier tests, which do not fully replicate clinical aerosol conditions. These limitations highlight the need for strategies that enable active viral inactivation during AGP.
Commercially available DUWL disinfectants such as sodium hypochlorite, HP, and chlorine dioxide are effective against a broad spectrum of microorganisms, but most of these agents are mucosal-irritating chemicals [7]. A review by Wu et al (2022) highlighted that several antimicrobial mouthwashes such as CHX and HP were effective in bacterial reduction of the DUWL, thus improving the quality of the DUWL [8]. However, their potential as continuous DUWL disinfection in mitigating aerosolized SARS-CoV-2 has yet to be explored.
Building on findings from various studies suggesting that mouthwash can reduce the SARS-CoV-2 viral load, this study tested a novel strategy of incorporating selected mouthwashes into DUWL systems. This approach aims to provide sustained antiviral action during AGP, thereby reducing the risk of bioaerosol transmission in dental practice.
To assess its feasibility, we developed a custom-designed, 3D-printed aerosol simulation model that mimics clinically relevant AGP conditions. This study is among the first to evaluate the inactivation of a SARS-CoV-2 surrogate, human coronavirus OC43 (HCoV-OC43), using mouthwashes introduced via DUWL under dynamic aerosolized conditions. HCoV-OC43 was selected in accordance with international biosafety recommendations because it is an enveloped Beta coronavirus with spike and structural homology to SARS-CoV-2 and is widely validated for virucidal testing under BSL-2 laboratory conditions.
The aim of this study was to evaluate a novel approach for integrating a non-irritating antiviral mouthwash into the dental unit waterline (DUWL) to enable continuous delivery during AGP. It was hypothesized that this method would inactivate aerosolized surrogate SARS-CoV-2 during AGP, thereby reducing the risk of viral aerosol transmission in the clinical setting.
Material and Methods
VIRUS AND CELL CULTURE:
Human intestinal epithelial cells, HCT-8 (ATCC CCL-244) were maintained in RPMI 1640 (Gibco, Thermo Fisher Scientific, Inc., Waltham, MA, USA) supplemented with 10% heat-inactivated fetal bovine serum, sodium pyruvate, and L-glutamine. These cells were cultured at 37°C under 5% CO2.
Human coronavirus OC43 (hCoV-OC43) (ATCC VR-1558), a surrogate SARS-CoV-2 virus, was propagated in HCT-8 cells. It was cultured in RPMI-1640 supplemented with 2% heat-inactivated fetal bovine serum, 1% penicillin-streptomycin, sodium pyruvate, and L-glutamine and incubated at 33°C in a humidified 5% CO2 atmosphere. When a 90% visual cytopathic effect (CPE) was observed, the infected cells underwent 3 freeze-thawing cycles to release the intracellular virus and centrifuged to eliminate any cell debris. The virus suspension was aliquoted and stored at −80°C for future use. All experiments involving live HCoV-OC43 were conducted in certified BSL-2 laboratories in full accordance with institutional biosafety regulations and international guidelines.
VIRUS TITRATION:
Viral titration assay was performed as described by Spearman-Kärber [9]. HCT-8 with a concentration of 2.49×106 TCID50/mL was seeded in 96-well plates. HCT-8 cells were 80% confluent and less than 48 hours before the virus inoculation. Serial 10-fold dilutions of virus stock, which was prepared in RPMI 1640 supplemented with 2% heat-inactivated fetal bovine serum, 1% penicillin-streptomycin, sodium pyruvate, and L-glutamine, were propagated onto HCT-8 cells. The virus-seeded cells were incubated at 33°C under 5% CO2 and observed daily under light microscopy for cytopathic effect (CPE) for up to 5 days. Observation of CPE indicated the presence of viable viruses. The number of wells with CPE was counted and the tissue culture infectious dose (TCID50) was obtained.
QUANTITATIVE SUSPENSION TEST:
Quantitative suspension test was carried out as described in ASTM E1052-20 [10]. Commercially available ready-to-use mouthwashes – 0.12% chlorhexidine digluconate (CHX) (Colgate® Periogard®, Colgate-Palmolive), 0.07% Cetylpyridinium Chloride (CPC) (Colgate® Plax, Colgate-Palmolive), 1% Hydrogen Peroxide (HP) (Colgate® Peroxyl®, Colgate-Palmolive), 0.2% PVP-I (Povidone-Iodine) (Betadine®), and Oral 7® rehydrating mouthwash (Oral 7®) – were used as test disinfectants. The pure ingredient of 0.2% CHX (Sigma Aldrich, St. Louis, MO, USA) and 0.07% CPC (Sigma Aldrich, St. Louis, MO, USA) were also tested to assess the efficacy of the active ingredient without interference of other ingredient in these 2 mouthwashes. Negative (distilled water) and positive (70% ethanol) controls were included and run under identical conditions. We added 0.1 mL of the virus suspension to 0.9 mL of the test mouthwash, mixed well using a vortex mixer. The virus was exposed to the mouthwash at 3 different exposure times (30 s, 2 min, and 5 min). Once it reached the exposure time, the microbial activity was immediately neutralized with soya casein digest lecithin polysorbate broth (SCDLP broth) (Orioner), and serial 10-fold dilutions were prepared. The diluted samples (0.1 mL) in each 96-well plate containing HCT-8 cells were incubated for 5 days. Cells were observed daily for CPE for up to 5 days. Log10 reduction value (LRV) was determined. Experiments were repeated 5 times for each designated exposure time point (n=5).
CYTOTOXICITY TEST:
Cytotoxicity testing was carried out as described in ASTM E1052-20, in which cells were exposed to the mouthwash mixture [10]. The mixture was made up of 1 part of RPMI 1640 and 9 parts of test mouthwash. It was then neutralized with SCDLP broth. Serial 10-fold dilutions were prepared and propagated in 96-well plates containing HCT-8 cells. Morphology of the cells and the cell growth were observed by light microscopy after 5 days.
QUANTITATIVE CARRIER TEST:
The virucidal activity of disinfectant agents is more challenging on dried surfaces than when the virus is in suspension. Quantitative carrier testing was conducted according to ASTM E1053-20 to evaluate the antiviral efficacy of the dried virus inoculum on surfaces [11]. We placed 50 μL OC-43 virus inoculum (concentration of 2.49×106 TCID50/mL) on a glass cover slide (22×22 mm) and allowed it to dry for 30 min at room temperature. We added 100 μL of mouthwash to the dried virus inoculum. After reaching the exposure time (30 s, 2 min, and 5 min), the microbial activity was immediately neutralized with SCDLP broth. The virus-mouthwash-SCDLP mixture on the cover slide was collected to recover the residual virus, and serial 10-fold dilutions were prepared. The diluted samples (0.1mL) were inoculated in each 96-well plate containing HCT-8 cells and incubated for 5 days. Cells were observed daily for CPE, and the cytotoxicity of the cells was also observed for up to 5 days. LRV was determined. Similarly, each exposure time was repeated 5 times (n=5) for consistency.
PREPARATION OF AEROSOL MODEL:
The aerosol model was designed using Tinkercad software (Figures 1, 2), and 3D printed using resin (Figure 3). The 3D-printed aerosol model was validated for absence of leakage using colored-powder tracer testing prior to all viral experiments, and iterative modifications were made until no tracer leakage was observed during AGP generation from the ultrasonic scaler.
AEROSOL TEST:
A 3D-printed model resembling the oral cavity was used to create an aerosolized environment. The model was operated in a standard laboratory room under ambient conditions. A petri dish (60×60 mm) containing HCoV-OC43 (concentration of 2.49×106 TCID50/mL) was placed at the bottom of the model (Figure 2). A portable scaler handpiece unit was filled with a test mouthwash solution. The most effective antiviral disinfectants in the first part of the experiment (quantitative suspension and carrier tests) were selected for the aerosol test. The dispensing of disinfectant solution from the handpiece was carried out for 30 s, 2 min, and 5 min.
Prior to the aerosol test, the water flow rate to the handpiece was estimated by collecting the effluent into the beaker for 30 s. The collected volume averaged approximately 5 mL, corresponding to an estimated flow rate of approximately 10 mL/min. Environmental parameters, such as relative humidity, air velocity, temperature, and aerosol particle size distribution were not directly measured during the experiments. Distilled water was used as a negative control. Each exposure time was tested 5 times independently (n=5) to ensure reproducibility.
Following the timed exposure, the aerosol sampling was collected from the model (Figure 1). The aerosol-contaminated surfaces in the model were obtained by swab sampling from both sides of the model and the side of the petri dish (Figure 2). The collected samples (both swab and aerosol) were vortexed for 15 s using a vortex mixer and examined for viability of the virus. Cytotoxicity, CPE observation, and determination of LRV were carried out similarly, as described above.
DATA ANALYSIS:
The viral titre in all tests was determined using the Spearman-Kärber method and and expressed as median (50%) tissue culture infectious dose (TCID50/ml). Virucidal activity was quantified as the difference in reduction in virus titre compared to the control (LRV). A virus titre reduction of ≥4 log10, which is equivalent to a ≥99.99% kill rate, is considered indicative of effective disinfectant activity.
Statistical analysis was performed using two-way ANOVA with Tukey’s multiple comparison test (
Results
QUANTITATIVE SUSPENSION TEST:
Table 1 shows the virus titres and LRV of hCoV-OC43 after exposure in the 5 commercially available mouthwashes (0.12% CHX, 0.07% CPC, 1% HP, 0.2% PVP-I, and Oral 7®) for 30 s, 2 min, and 5 min. Overall, there was a significant reduction (P<0.0001) in virus titre compared to the control group. All mouthwashes showed at least 3.0 log10 reduction of viral titre at all exposure times (30 s, 2 min, and 5 min). At the short exposure time of 30 s, 3 mouthwashes – 0.07% CPC, 0.2% PVP-I, and Oral 7® – showed a reduction of 4.9 log10 TCID50/ml, which correspondent to ≥99.9% reduction in viral load. This reduction was statistically significant (P<0.0001).
Both the pure and commercially available 0.12% CHX showed a significant (
The pure ingredient of CPC and CHX were tested, and the result was very similar to that of the commercially available CPC and CHX mouthwashes. Among all tested mouthwashes, only 0.2% PVP-I and Oral 7® did not show cytotoxic effect on HCT-8 cells, whereas the others showed mild cytotoxic effects even at 10−1 dilution.
We were unable to calculate the 95% CI for PVP-I, CPC, and Oral7® because all replicates produced identical results. The tests were based on a binary (yes/no) evaluation of viral inactivation. For samples with complete viral inactivation, the minimum detectable viral load was 1.5 log10 TCID50/mL, as determined by the Spearman-Kärber method.
QUANTITATIVE CARRIER TEST:
Table 2 showed the result for quantitative carrier test. Overall, all mouthwashes significantly reduced the presence of viable virus on the glass coverslips after exposure for 30 seconds, 2 minutes, and 5 minutes, compared with the initial viral load in the RPMI solution (p<0.0001). Upon an exposure time of 5 min, a significant reduction of at least 3.0 log10 (p<0.0001) was detected for all the mouthwashes.
Similar to the suspension test, the 3 mouthwashes (0.07% CPC, 0.2% PVP-I and Oral 7®) demonstrated the most significant antiviral effect (
Similar to the suspension test, among all the tested mouthwashes, only 0.2% PVP-I and Oral 7® did not exhibit cytotoxic effects on HCT-8 cells, while the other mouthwashes showed mild cytotoxicity even at a 10−1 dilution.
AEROSOL TEST:
Figure 4 shows the results of the aerosol tests. In the control group, the aerosol samples had a mean log10 TCID50 viral titre of 2.6±0.137 at 30 s and 5 min, and 2.65±0.137 at 2 min.
When compared with the control group, 0.07% CPC, 0.2% PVP-I, and Oral 7® significantly (
Discussion
The oral cavity is an important site for SARS-CoV-2 infection due to the presence of ACE-2, neuropilin-1 (NRP-1), and transmembrane serine protease 2 (TMPRSS2) in the oral cavity [12], which allow the virus to replicate and transmit to others. To minimize the pathogens at the primary site, preoperative mouthwash might be able to address this concern effectively. Thus, this approach holds the potential to temporarily lower the viral load in droplets and aerosols, which indirectly reduces the likelihood of viral transmission [3].
Due to the COVID-19 pandemic, preprocedural mouthwashes have garnered renewed interest as a practical approach to mitigating the spread of SARS-CoV-2 in healthcare environments. A systematic review conducted by Ziaeefar et al (2022) showed that mouthwashes can reduce the SARS-CoV-2 viral load, consistent with findings from other systematic reviews [13–15]. This agrees with our results, where all mouthwashes reduced viral load within 30 s. However, only 3 mouthwashes (CPC, PVP-I, and Oral 7®) exhibited effective inactivation of SARS-CoV-2, achieving nearly 99.99% reduction within 30 s in both suspension and carrier tests, suggesting rapid virus inactivation.
Interestingly, among all the mouthwashes tested, only PVP-I and Oral 7® demonstrated strong virucidal activity against the surrogate SARS-CoV-2 virus while remaining non-cytotoxic, even after 5 min of exposure. Although in vitro cytotoxicity is often reported [16], these findings must be interpreted with caution. Moharamzadeh et al (2009) compared mouthwash effects on a monolayer gingival fibroblast model versus a more physiologically relevant 3D oral mucosal model [17]. They found cytotoxicity in a monolayer gingival fibroblast model, but not in the 3D oral mucosal model containing epithelial and connective tissue, suggesting that monolayer assays sometimes overestimate cytotoxicity due to direct, unbuffered exposure of cells to active ingredients. Although monolayer cell cultures provide a simplified representation of human tissues and serve as an important preliminary indication of cytotoxic potential, the cytotoxicity observed in these model does not always translate directly to 3D tissues or in vivo systems, as the latter possess additional structural and physiological barriers that can reduce cellular damage. Therefore, cytotoxicity observed in monolayer assays may not fully reflect the safety profile of mouthwashes under clinical conditions.
PVP-I demonstrated a broad virucidal spectrum covering both non-enveloped and enveloped viruses, including SARS-CoV-2, rotavirus, poliovirus, rubella virus, influenza virus, and herpes virus [19]. Its mechanism is attributed to the release of free iodine, which destabilizes the viral envelope and disrupts viral proteins. Thus, this may exacerbate viral disruption, alter their metabolic pathways, and ultimately cause irreversible damage to the virus [19,20]. Although there are concerns about the potential adverse effect of PVP-I mouthwash, such as transient hypothyroidism due to the ingestion of iodine [21], studies have reported that prolonged use of PVP-I mouthwash did not cause any mucosal irritation or other adverse effects for up to 28 months [20,22]. Additionally, Frank et al (2020) observed no cytotoxic effects despite a concentration of 5% PVP-I nasal antiseptic being used, which is consistent with our findings [23]. This is likely due to the povidone complex, which act as a controlled-release carrier regulating iodine reactivity. It is believed that iodine is released slowly into the surrounding environment, thereby lowering cytotoxicity while maintaining antimicrobial efficacy [24].
Oral 7®, formulated with natural enzymes such as lysozyme and the cationic glycoprotein lactoferrin, demonstrated strong virucidal without cytotoxic effects. Lactoferrin has been shown to exert antiviral action by binding to host cell surface heparan sulfate proteoglycans and viral particles. This interaction helps to prevent viral adsorption without causing cytotoxic effects on host cells [25,26]. However, lysozymes may enhance immune response and reduce viral infections [27,28]. As an intrinsic element of the human immune defence, lysozyme selectively targets bacterial cell walls without affecting mammalian cell membranes, and is thereby less cytotoxic to the cells [29]. Besides being a mouthwash, Oral 7® also offers a saliva substitute product containing similar active ingredients (lactoferrin and lysozyme) intended for continuous use as a lubricant for the oral mucosa. Our findings suggest that the Oral 7® saliva substitute has antiviral benefits and could be a safer alternative for continuous mucosal application.
Both pure and commercially available CPC achieved a 4 log10 reduction but exhibited cytotoxicity on cells in vitro. Müller et al (2017) reported the cytotoxicity of CPC mouthwash to human keratinocytes and L929 cells at the dilution of 10−1, likely due to the active ingredients (antimicrobial salt and cationic surfactant) present in the mouthwash [16]. Therefore, it was confirmed that CPC exhibits cytotoxic effects on cells in vitro. The cytotoxicity of CPC on human epithelial cells was dependent of the concentration of the mouthwash and its reference compound. In general, lower concentrations of the active ingredient in the mouthwash were less cytotoxic to the cells [30].
To safely study the antiviral properties of the mouthwashes, we utilised HCoV-OC43 in this study as a surrogate for SARS-CoV-2. This is because both SARS-Cov-2 and HCoV-OC43 belong to the Beta coronavirus genus, which causes respiratory infections [31]. SARS-CoV-2 and HCoV-OC43 viruses demonstrate replication in human respiratory epithelial cells and spread primarily through aerosols and respiratory droplets [32]. They also share similar structural proteins, particularly the envelope and spike proteins [33], making it a relevant model for virucidal testing. Unlike SARS-CoV-2, HCoV-OC43 can be safely handled under BSL-2, significantly lowering the risk to researchers while allowing reliable and ethical experimental assessment. This approach enables robust testing of antiviral mouthwash potential without the logistical and safety constraints associated with high-containment laboratories.
DUWL disinfectants are not designed for prolonged continuous use and their effect on the virus dispersion in aerosol is understudied [34]. A recent study found that 2 commonly used disinfectants – ICX (containing sodium percarbonate and silver nitrate) and Alpron (containing chloramine-T and polyhexanide biguanide) – when added continuously to DUWL, effectively reduced the viable viruses load in aerosol, but their cytotoxicity to human cells remains unknown [34].
To address this, we selected mouthwashes as test disinfectants for DUWL systems due to their safety for continuous use without harming the oral mucosa. Our study revealed that the continuous use of CPC, PVP-I, and Oral 7® as irrigation solutions can effectively reduce the dispersion of aerosolized viruses. Pawar et al (2016) incorporated various mouthwashes into the DUWL as more cost-effective and readily available disinfectants. Lower concentrations were used for continuous application, while higher concentrations of mouthwash were exclusively used for overnight treatment. All disinfectants proved equally effective in reducing microbial colony counts in DUWLs, irrespective of their concentration [35].
However, the potential adverse effects of DUWL disinfectants, including brownish discoloration of DUWL output water, staining of dental instruments, degradation and blockage of tubing, and irritation of oral mucosa, should not be overlooked [8], particularly when mouthwash is used as a routine DUWL disinfectant. The impact of continuous dispersion of PVP-I, CPC, and Oral 7® on the enamel and dentin bond strength of the dental adhesive material was not been assessed in this study. It is also important to assess the effect of PVP-I, CPC and Oral 7® on waterline tubing in the future research. Additionally, repeated contact with oral mucosa may raise safety considerations, particularly for formulations consisting of active antiseptic, which is cytotoxic to the cells, or in patients with known allergies. Hence, in vivo studies are needed to evaluate these effects, assisting in assessment of the feasibility and long-term effects of implementing dispersion of mouthwash as DUWL disinfectants continuously as an important preventive measure in dentistry. However, considering the ease of viral transmission through saliva and the constant mutation of viruses over time, COVID-19 is unlikely to be the last respiratory disease to affect us [36]. It is imperative to find alternative methods to effectively inactivate the virus in AGPs to address potential shortages of personal protective equipment in future pandemics.
Previous studies on virucidal activity of mouthwash have relied on settled plate assays and did not assess viral contamination in aerosols, leaving a critical gap in understanding [37]. Capturing virus-laden aerosol samples is challenging due to the low viable aerosolized virus concentration and variability in sampling conditions. In addition, current air sampling technology fails to simulate actual human respiratory infection mechanisms, so negative results might not indicate the absence of aerosolized virus [38]. To address these shortcomings, we developed a novel aerosol model designed to eliminate aerosol leakage while enabling a more realistic simulation. According to the NIOSH Manual of Analytical Methods, reducing the high flow rate is recommended to optimize collection efficiency [39]. Therefore, to preserve the structural integrity of the virus, manual manipulation was used during aerosol collection to minimize shear stress, which can compromise viral viability.
Environmental contamination by virus-laden aerosols is often overlooked. Recent studies have shown that aerosolized SARS-CoV-2 remains viable in the air even after 1 h [40]. However, a negative result from aerosol sampling does not necessarily indicate the absence of the virus in the air, as viral particles can eventually settle onto surfaces [38]. Therefore, surface sampling studies should be conducted along with aerosol sampling in the future. A comparison of surface sampling and aerosol sampling results will provide definite insight into the feasibility of the approach.
Future studies should focus on improved bioaerosol sampling to address uncertainties in aerosolized virus behavior and assess the long-term effects of mouthwash on DUWL tubing and bonding integrity with prolonged use. In this study, we did not directly measure all physical parameters of the aerosol (eg, continuous air velocity, full particle size distribution, and real-time aerosol mass concentration). Although the model was designed to approximate clinical AGP conditions and was compared with published dental aerosol data, the lack of in situ particle characterization and the inability to measure air pressure may limit quantitative extrapolation to real-world settings. This limitation arose because the procedure was performed manually. As the applied force and steadiness of hand operation are difficult to standardize, obtaining consistent pressure measurements was challenging. However, the sampling process was standardized by maintaining a consistent pump duration of 10 s for each trial. In addition, experiments were conducted in a laboratory room without clinical suction; thus, aerosol dispersion may differ from typical clinical environments.
In vitro cytotoxicity findings reflect the sensitivity of monolayer cell cultures and do not directly predict mucosal irritation potential in vivo. Future studies should focus on improving bioaerosol sampling, real-time particle monitoring (eg, using aerodynamic particle sizers), controlled environmental conditions, and assessment of tubing durability to better understand the behavior of aerosolized viruses and the practical applicability of mouthwash-based continuous disinfection.
Conclusions
In this in vitro study, 0.07% CPC, 0.2% PVP-I, and Oral 7® effectively reduced aerosolized surrogate SARS-CoV-2 within 30 s. Only PVP-I and Oral 7® were non-cytotoxic in cell culture. These findings suggest that selected mouthwashes have potential as part of infection control strategies in dental settings, but further in vivo or clinical validation is required before routine implementation.
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