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

OBJECTIVE: To provide a narrative review of the preprocedural mouth rinse protocols suggested for oral surgery in order to contrast the presence of SARS-CoV-2 in aerosol. SOURCES AND METHODS: Electronic searches were performed in medical databases PubMed, Medline, CINAHN and Scopus to identify relevant studies published up until the third week of April 2020. This research was supplemented by exploration through a web-based search engine as well as a manual search for international and national guidelines. Studies and protocols which suggested preoperative mouth rinsing as a recommended measure during the COVID-19 outbreak were included. Given the small number of studies, a narrative literature review was conducted. In total, 15 references (11 articles and 4 guidelines) were considered relevant and were critically analysed.
CONCLUSION: The findings show a high heterogeneity in the protocols suggested. Further research is required to better understand the viral features and epidemiologic characteristics of this new virus and to test the efficacy of commonly used antiseptics against SARS-CoV-2 in future clinical trials. However, the use of chlorhexidine, hydrogen peroxide, PVP-I and cetylpyridinium chloride in contrasting the spread of Covid-19 is described as advisable and substantial in different publications.

Introduction

Dentists present the greatest risk of exposure of medical practitioners to the infection of COVID-19, as they are brought in much closer contact with patients than is the case with practitioners in other fields of medicine (). Oral surgery such as implant placement, immediate loading procedures, complex tooth extractions or guided bone regenerations require the use of tools and devices which produce aerosol and spatters. Surgical areas contain many devices such as implant and surgical motors, anaesthesiologic pumps, surgical lamps, blood centrifuges, which are not normally present in standard dental rooms.

Therefore, dentists and oral surgeons are exposed to high quantities of spray produced by dental instruments placed inside the mouth, where many microorganisms can be found (). Since SARS-CoV-2 has a very high affinity not only for the epithelial cells of the lungs but also for those of the salivary glands, a considerable amount of the virus is continuously excreted with saliva in infected subjects (, ). From there, it can pass into the aerosol created during the procedures and be inhaled by the operator. The same principle applies for all devices which produce spray, such as ultrasonic scalers, surgical implant motors and the air-water syringe found in dental units (, -).

Dental aerosols produced during surgical procedures can contain a large number of bacteria and viruses (, ). It has been established that microorganisms in dental aerosols can still cause infections after remaining in an environment for extended periods although there is no definite evidence of transmission of infectious pathogens through dental aerosols (, , -).

Van Doremalen () and Chin () tested the presence of the SARS-CoV-2 on different materials. They reported that on several materials such as plastic, stainless steel and, also surgical masks the virus can be detected for up to 4 days (Figure 1).

Figure 1

Flow of the search and selection process

Moreover, the high risk of transmission of the virus, the exponential increase in positive cases and the existence of asymptomatic or paucisymptomatic carriers with a high viral load obliges dental practice staff to consider all patients undergoing a surgical procedure as potentially infected, even if the relative transmissibility of asymptomatic COVID-19 infections it is not yet fully clear (-). The aim of the present study was to identify in the available literature, the role, possible uses, efficacy and side effects of different active ingredients contained in many common mouthwashes against the new SARS-CoV-2 with special consideration of surgical dental procedures.

Materials and methods

An online review of scientific articles was performed using medical databases such as PubMed, MedLine, CINAHN and Scopus. Due to the overall small number of relevant publications, single publications as well as digital articles on websites were included in the initial search. With the keywords “COVID” and “dentistry” or “dental” or “oral surgery”, 48 references were found by the date of 31st of August 2020. Possible duplicates were excluded based on article titles. Furthermore, all abstracts underwent an initial screening to eliminate articles which were not related to our aim of establishing the possible uses of different active ingredients in the common mouth washing agents. Several international guidelines published in different countries (5 in total) have also been found.

After the initial screening and the exclusion of duplicates and studies not relevant to the topic, the full texts of candidate sources in the field of dentistry regarding the pathology of COVID-19 until 1st of September 2020 were analysed. Although the content of the articles was wide-ranging, a large number of them were able to provide recommendations for ensuring the safety and protection of the operator during oral surgery. On the specific topic of mouth rinses, in September 2020, just a few publications (23 references in total, 19 articles and 4 guidelines) have been found with the keywords “COVID” and “Mouth rinse” or “Mouthwash”. However, only one article, with a limited analysis, was specifically related to the field of oral surgery.

Results

Given the relative ignorance of current medicine on this virus, which emerged only at the end of 2019, it is not surprising that limited data are yet available to show whether an active ingredient present in a mouthwash can be effective when used as a pre-procedural rinse or as a home rinse by a patient with COVID-19. In late August 2020, only a limited number of publications related to SARS-CoV-2 and dentistry were available, and only few of them proposed different kinds of active substances as pre-procedural mouth rinses: hydrogen peroxide 1%, povidone-iodine 1% (PVP-I), cetylpyridinium chloride (CPC) 0.1%, essential oils and chlorhexidine. Essential conclusions of cited publications are reported in Table 1. It is immediately evident that there is a high degree of heterogeneity between these protocols proposed; hence a critical review analysis is proposed to lead the clinicians' choices.

Table 1

Published articles, reviews and guidelines reporting recommendations on preprocedural mouth rinses against infection of SARS-CoV-2.

Authors	Publication date	Considerations on preprocedural mouth rinse	Considered active principles
Peng X et al. 20(Article)	March 2020	“Agents such as 1% hydrogen peroxide or 0.2% povidone are recommended, for the purpose of reducing the salivary load of oral microbes, including potential 2019-nCoV carriage.Chlorhexidine, which is commonly used as mouth rinse in dental practice, may not be effective to kill 2019-nCoV. Since 2019-nCoV is vulnerable to oxidation, a pre-procedural mouth rinse containing oxidative.”	• Hydrogen peroxide• Povidone-iodine• Chlorhexidine
Ather A et al. 25(Article)	March 2020	“Previous studies have shown that SARS and MERS were highly susceptible to povidone-iodine mouthwashes. Therefore, pre-procedural mouth rinse with 0, 2% povidone-iodine might reduce the load of coronaviruses in saliva.”	• Povidone-iodine
Li ZY, Meng LY. 26(Article)	February 2020	“Before oral examination, patients can rinse with 1% povidone-iodine, CPC (0, 05% ~ 0, 10%) or a mouthwash containing essential oils. In vitro papers show gargling with povidone-iodine can inactivate SARS-CoV (responsible of 2020 epidemic) and CPC could inactivate MERS-Cov.”	• Povidone-iodine• Cetylpyridinium chloride• Essential oils
Italian society of Periodontology and Implantology32(Guidelines)	March 2020	“A rinse with a 1% solution of hydrogen peroxide (one part of hydrogen peroxide at 10 volumes / 3% and two parts of water) or with Povidone-iodine 1% could have an effect on the viruses present in the patient's oral cavity, with final gargling for 30 sec. Subsequently prescribe a further rinse with Chlorhexidine 0.2 - 0.3% mouthwash for 1 minute: Chlorhexidine does not appear effective in deactivating the virus, but is able to reduce the bacterial load in the aerosol.”	• Hydrogen peroxide• Povidone-iodine• Chlorhexidine•
Ge ZY et al. 33(Article)	March 2020	“CHX is effective against several infectious viruses, including herpes simplex virus (HSV), human immunodeficiency virus (HIV), and hepatitis B virus (HBV). About 0.12% CHX was used as a pre-procedural mouth rinse. For patients who develop mucosal irritation or other side effects such as tongue stain, 0.05% CPC could be a good alternative.”	• Chlorhexidine     Cetylpyridinium chloride
Australian Dental Association 34(Guidelines)	March 2020	“While the efficacy of this approach cannot be guaranteed to have a significant effect on viral load in a patient with COVID-19, we recommend that prior to commencing treatment all patients should be asked to undertake a 20-30 second pre-procedural mouth rinse with either: • 1% hydrogen peroxide • 0.2% povidone iodine• 0.2% chlorhexidine rinse (alcohol free)• an essential oil mouth rinse (alcohol free).”	• Hydrogen peroxide• Povidone-iodine• Chlorhexidine (alcohol-free)• Essential oils (alcohol-free)
American Dental Association 36(Guidelines)	March 2020	“Since SARS-CoV-2 may be vulnerable to oxidation, use 1.5% hydrogen peroxide (commercially available in the US) or 0.2% povidone as a preprocedural mouth rinse. There are no clinical studies supporting the virucidal effects of any preprocedural mouth rinse against SARS-CoV-2.”	• Hydrogen peroxide• Povidone-iodine
Meng L, Hua F, Bian Z. 40(Article)	March 2020	“Preoperative antimicrobial mouth rinse could reduce the number of microbes in the oral cavity.”	None
Basso M et al. 42(Review)	March 2020	“Considering the general costs for the patient and professional, availability on the market, ease of use, interactions and side effects of the two principles that can be used, the following treatment is suggested:1. Gargle with 1% hydrogen peroxide mouthwash for at least 15 seconds with a final rinse of 30 seconds. When done, do not rinse with water but immediately proceed to:2. Rinse with 0.20% chlorhexidine mouth rinse for at least 60 seconds and then gargle for at least 15 seconds. Do not rinse with water.”	• Hydrogen peroxide• Povidone-iodine• Chlorhexidine• Cetylpyridinium chloride• Essential oils
Ahmed MS 43(Review)	February 2020	“A preoperational antimicrobial mouth rinse is generally used by many practitioners to reduce the number of oral microbes. However, the National Health Commission of the People’s Republic of China advocated that chlorhexidine, which is commonly used as mouth rinse in dental practice, may not be effective to kill corona virus. Since corona virus is vulnerable to oxidation, preprocedural mouth rinse containing oxidative agents such as 1% hydrogen peroxide or 0.2% povidone is recommended, for the purpose of reducing the salivary load of oral microbes.”	• Hydrogen peroxide• Povidone-iodine
Czech Dental Association44(Guidelines)	March 2020	“Different solutions can be used as a pre-procedural mouth rinse, for example 1% hydrogen peroxide, a combination of alcohol and 0,2% chlorhexidine (can be used alone or in combination) or 0,2% povidone (restrictions for possible allergies).”	• Hydrogen peroxide• Chlorhexidine (with alcohol)• Povidone-iodine
Alharbi et al.45	April 2020	“Using 0.23% povidone-iodine mouthwash for at least 15s before the procedure can reduce the viral load in the patient’s saliva”	• Povidone-iodine
Fallahi et al.46	April 2020	“The effect of chlorhexidine, which is commonly used forpre-procedural mouth washing in dental practice, has notyet been demonstrated to be capable of eliminating 2019-nCoV. However, oxidative agents containing mouth rinseswith 1% hydrogen peroxide or 0.2% povidone-iodine arerecommended”	• Hydrogen peroxide• Povidone-iodine
Izzetti at al.47	April 2020	“Mouth rinses containing 1% hydrogen peroxide or 0.2% povidone can be employed to reduce microbial load in saliva, with a potential effect on SARS-CoV-2.”“The Italian recommendationdocuments are suggesting a preoperative 1-minmouth rinse with 0.2% to 1% povidone, 0.05% to 0.1% cetylpyridinium chloride, or 1% hydrogen peroxide.”	• Hydrogen peroxide• Povidone-iodine• Cetylpyridinium chloride
Ren et al.48	April 2020	“Povidone-iodine mouthwash has been shown to have strong viricidal activities againstSARS-CoV and MERS-CoV after 15 s of exposure. (…)For aerosol-generating procedures, patients should be instructed to use 1% povidone-iodine or 1.5% hydrogen peroxide mouth rinses for 1 min before the procedure.”	• Hydrogen peroxide• Povidone-iodine
O’Donnell et al.49	May 2020	“Dental practitioners are at elevated risk of exposure to SARSCoV-2, and there are guidelines that advocate the use of mouthwash clinically.Preprocedural mouthwash to reduce the oral microbial load in patients undergoing dental treatment in patients with SARS-CoV-2 is recommended by literature.”	• Chlorhexidine• Povidone-iodine• Chlorinated Water or Hypertonic Saline Rinsing• Hydrogen peroxide• Quaternary ammonium compounds
Kerawala et al.50SPECIFIC TOPIC: SURGERY	May 2020	“The virucidal activity ofPVP against SARS-CoV-2 has not been documented. The suggestion that tempering Chlorhexidine rinses (47 ◦Cvs 18 ◦C) may reduce bacterial aerosol contamination furtheris untried with viral load.”	• Povidone-Iodine• Chlorhexidine (tempered 47°)
Kelly et al.51	Jun 2020	“There is currently insufficient high-quality evidence to suggest that oral rinses are effective against SARS-CoV-2. While a number of guidelines have suggested the use of oral rinses as a prophylactic measure, this should not be as an alternative to high quality personal protective equipment (PPE) and rigorous cross infection control”	• Chlorhexidine• Povidone-iodine• Hydrogen peroxide• Ethanol
Dexter et al.52	Jul 2020	“Both agents (CHX and PVP-I) have broad activity againstbacteria and viruses that will serve to protect patients and providers from subsequent transmission.”	• Chlorhexidine• Povidone-iodine
Martinez-Lamas et al. 53IN VIVO	Jul 2020	“These preliminary in vivo results suggest that a PVP-I rinse could reduce the saliva viral load of SARS-CoV-2 in patients with higher viral loads. Therefore, routine administration of PVP-Icould be primarily indicated for symptomatic patients infected with SARS-CoV-2.”	• Povidone-iodine
Meister et al.54	Jul 2020	“Experimental and clinicalresearch studies on SARS-CoV-2–related viruses showed that antiseptic solutions containing chlorhexidine gluconate, PVP-I, chlorine dioxide, cetylpyridiniumchloride and hydrogen peroxide can indeed reduce viral loads.”	• Chlorhexidine 0,2%• Povidone-iodine• Et. Essential Oils• Benzalconium Chloride• Hydrogen peroxide• Octenidine• Polyhexanide
Moosavi et al.55	Jul 2020	“The use of mouthwash before dental procedures to reduce the risk of transmission of the virus to the dental team and the use of this mouthwash in COVID-19 patients to help improve systemic problems associated with oral microbial flora.”	• Chlorhexidine• Povidone-iodine• C31 G
Vergara-Buenaventura et Castro Ruiz.56	Aug 2020	“Suggested recommendations: Gently gargle for 30 seconds in the oral cavity and 30 seconds in the back of the throat with: 1.5% or 3% H2O2 15 ml; PVP-I, 0.2%, 0.4%, or 0.5% 9 ml; 0.12% CHX 15 ml; or 0.05% CPC 15 ml.”	• Chlorhexidine• Povidone-iodine• Hydrogen peroxide• Cetylpyridinium Chloride
Eliades et al.57ORTHODONTICS	Sep 2020	Preprocedural antiseptic protocol in orthodontics:     1. Mouthrinse with (47°C) CHX 0.12%- 0.2% for bacterial pathogens (0.5-1 min).     2. Mouthrinse with 0.2%-1% PI or 1% H2O2 for oxidation vulnerable viruses (0.5-1 min)	• Chlorhexidine• Povidone-iodine• Hydrogen peroxide• Chloride dioxide• Herbal compounds• Cetylpiridinium chloride• Cyclodextrine & flavonoids

The antiseptics analysed were hydrogen peroxide, povidone-iodine, cetylpyridinium chloride (CPC), essential oils, and chlorhexidine (Table 2).

Table 2

The effect of various disinfectants on SARS-CoV-2. Detection limit of a typical TCID50 assay is 100 TCID50/mL, except for reactions containing hand soap/chloroxylenol (detection limit: 103 TCID50/mL) or reactions containing povidone-iodine/chlorhexidine/benzalkonium chloride (detection limit: 104 TCID50/mL). U: undetectable. This has been adapted with permission from the author 15.

	Virus titer (Log TCID50/mL)
DISINFECTANT	5 min	15 min	30 min
Hand soap solution (1:49)	3.6	U	U
Ethanol 70%	U	U	U
Povidone iodine 7.5%	U	U	U
Chloroxylenol 0.05%	U	U	U
Chlorhexidine 0.05%	U	U	U
Benzalkonium chloride 0.1%	U	U	U

Hydrogen peroxide ()

No specific literature addresses its virucidal activity against SARS-CoV-2. Peng et al. () reported that since the COVID-19 virus has been shown to be vulnerable to oxidation, as reported in the Guidelines for the Diagnosis and Treatment of Novel Coronavirus Pneumonia (5th edition), it is recommended to use a pre-procedural mouth rinse with hydrogen peroxide 1% to reduce the viral load. This recommendation is based on the behavior of other coronaviruses () exposed to hydrogen peroxide on different surfaces. Used in this way, a surface disinfectant with hydrogen peroxide 0.5% has proven effective in inactivating the virus in one minute ().

Povidone-iodine

Povidone-iodine is an oxidizing agent, which is also able to alter protein synthesis and lead to cell lysis. It is active against bacteria, viruses, fungi and spores. Povidone-iodine (PVP-I) is a compound obtained by combining the polyvinylpyrrolidone polymer (PVP) with iodine in the form of triiodide ions. Its possible role during SARS-CoV-2 pandemic has been reported by different publications (-).

Cetylpyridinium chloride (CPC)

Cetylpyridinium is active against bacteria, fungi and viruses. With regard to the SARS-CoV-2 coronavirus, the study by Li et al. () suggests that the right concentration of cetylpyridinium chloride should be between 0.05 and 0.10 if used as a preprocedural mouth rinse to reduce viral load of SARS-CoV-2.

Essential oils

Articles available for essential oils on SARS-CoV-2 are related to specific oils and concentrations (0.092% eucalyptol, 0.064% thymol, 0.060% methyl salicylate and 0.042% menthol), (). However, no clinical study has investigated an essential oil mouth rinse against SARS-CoV-2, either in vitro or in vivo.

Chlorhexidine

Chlorhexidine (-) is a biguanide considered the “gold standard” of chemical plaque control. The main side effects of chlorhexidine are linked to the formation of brownish-yellow pigmentation, although a recent review of the literature has demonstrated the efficacy of an anti-pigmentation system in counteracting the formation of chlorhexidine stains while maintaining the same efficacy (, ). As is the case with all other antiseptics, no available clinical study analyses the efficacy of chlorhexidine mouth rinse against SARS-CoV-2 in dentistry in vivo. Lim and Kam () showed that chlorhexidine has an important virucidal action, even against coronavirus species. Moreover, Chin et al. () demonstrated the virucidal efficacy of chlorhexidine and other standard dental disinfectants.

Discussion

Many active substances commonly used in mouth rinses were demonstrated to be effective against SARS-CoV-2 in laboratory studies or if used as surface disinfectants (-). At the moment, there is still a gap in the knowledge pertaining to the practical usefulness of mouth rinses in a patient with SARS-CoV-2 before a surgical procedure. Therefore, at present, deductions can be based solely on the action mechanism, the data related to similar viruses from the past, results obtained in vitro or in other non-dental fields and actions on inanimate surfaces in the field of disinfection. Furthermore, a proposed practical procedure of use needs to be based on an analysis of how these active ingredients must be prepared and used and an evaluation of any side effects caused by use. Italian guidelines (, ) (Italy was the first European country to be heavily affected by COVID-19), together with other international recommendations, recommend the use of chlorhexidine, stating that it would be completely irrational to interrupt the commonly used pre-procedural mouth rinse with chlorhexidine and that, it should be maintained and used together with a second one, suggesting hydrogen peroxide 1% or povidone-iodine 1% (-).

Hydrogen peroxide is recommended for use as a mouth rinse at a concentration of 1% (). Normally, the most frequently available formulation is 3%, also described “for food use”, and can be used as a disinfectant, mouth rinse, bleach for hair or nails and for animal care. A typical considerable production of gas bubbles could prevent its use for a sufficient time of at least 30 seconds. Hydrogen peroxide represents an extremely cost-effective product which can be found very easily on the market and has no important side effects other than slight local irritation or a burning sensation.

An increase in the use of povidone-iodine (PVP-I) 1% mouth rinse at dental clinics has been verified since the beginning of February 2020, especially when the first recommendations of scientific societies appeared (, , -). However, some more technical information with respect to the same guidelines must be given to oral surgeons on possible allergies or issues related to the use of an iodine-based product. Attention must be paid not only to people with hyperthyroidism, but also to cases of latent or subclinical hyperthyroidism. The product is also known to interact with drugs, such as lithium-based antidepressants. Povidone-iodine should be avoided in patients with renal insufficiency.

From a pharmacological point of view, the official drug information sheet of the only povidone-iodine 1% mouthrinse () registered by the manufacturer under European regulations, specifically instructs users to “avoid the simultaneous use of other mouth, gums and throat disinfectants” and, more specifically, “not to use products containing hydrogen peroxide simultaneously on the part treated with this medication”. This creates a possible conflict with some guidelines, which recommend the association between chlorhexidine and a choice between povidone-iodine or hydrogen peroxide to be used as a sequence of mouth rinses before operating sessions such as surgical procedures. Povidone-iodine mouthwash is still advised by many associations but only if it is not combined with any other substance, even if this means forfeiting the benefits of a second mouthwash with a different antimicrobial activity (, , , ).

Chlorhexidine is certainly the active ingredient most prescribed by dentists and best-known by patients. Chlorhexidine as an antiseptic has broad spectrum antimicrobial properties. The first publications on the new virus SARS-CoV-2 often questioned its efficacy, as no studies yet have demonstrated this action (, , -). However, some important in vitro studies have unequivocally shown the activity of chlorhexidine on many viral species, even at lower concentrations than those commonly used in mouth rinses (-)..

Coronaviruses are RNA viruses which are part of the order Nidovirales, suborder Cornidovirineae, family Coronaviridae, and subfamily Orthocoronavirinae. These viruses have their own viral envelopes with a positive-sense single-stranded genome and a helically symmetrical nucleocapsid. Therefore, if chlorhexidine is active against viruses with viral envelopes, it could be inferred that it might also be active against coronaviruses, including SARS-CoV-2.

Finally, chlorhexidine is considered to be the gold standard of oral antiseptics due to its substantivity, that is, the ability to bind to teeth and oral mucosa and be released for up to 12 hours (). This property might also be important in combatting SARS-CoV-2, which continuously contaminates the oral cavity through saliva drops from salivary glands; however, the proper role of substantivity in reducing the spread of COVID-19 still has to be investigated.

Several publications related to SARS-CoV-2 specifically stress the importance of gargling (, ). Wölfel et al. () showed that pharyngeal virus shedding was very high during the first week of symptoms, and the RNA peak concentration was 1000 times higher compared to studies of SARS concentrations. SARS-CoV-2 was successfully isolated from throat swabs, which is another significant difference between COVID and SARS, as the latter rarely allowed successful live virus isolation from throat swabs. This reveals that the correct usage of virucidal oral products can be fundamental for preventing the spread of the virus via breathing, coughing and contact with the oral cavity

Therefore, before a surgical session, it is highly advisable that the patient not only rinses but also completes this procedure with a gargle in order to bring the rinse into the tonsillar area and into the proximity of the throat as much as possible.

Conclusions

As described and considered in this article, and on the basis of the available literature until late August 2020 and from the international guidelines for SARS-CoV-2, the area of 3 meters around the patient’s mouth must be considered a high risk of contamination, and the use of effective mouth rinses can contribute in reducing the microbial load in aerosols. With regard to the mouth rinses, particularly before a surgical procedure, the following can be considered:

There is, yet, no mouth rinse which is scientifically proven to be effective against SARS-CoV-2 in the oral cavity. All guidelines or articles report activities against other types of viruses, and only a few contain data on the activity against SARS-CoV-2 in general, but not in the oral environment.

Oxidizing agents, such as hydrogen peroxide 1% and povidone-iodine (PVP-I) 1%, are advised in many international guidelines and articles for possible use as a mouth rinse against SARS-CoV-2 (, , -).

Povidone-iodine 1% presupposes considerations on the patient’s state of health. Side effects can be significant in the case of pregnancy, renal diseases, thyroid dysfunction or concomitant drug therapies. Simultaneous use of PVP-I and other disinfectants used as mouth rinses should be avoided.

Chlorhexidine was certainly proven to have antiviral activity against SARS-CoV-2 in laboratory studies (). The substantivity of chlorhexidine to prolong antiseptic activity until 12 hours after a rinse can be an important tool against the virus. The advantages of this property in combating COVID-19 have been described by Yoon () but clinical confirmations are still missing.

It can be considered advantageous to use a sequence of 2 different types of active ingredients to exploit a dual mechanism of action, both oxidative and antiseptic. The most rational association could be a 30” rinse with H2O2 at a concentration of 1%, followed by another 60” rinse with Chlorhexidine at a concentration of 0.2-0.3%. This sequence has been recently confirmed by the Italian scientific commission for national guidelines in dentistry against COVID-19 (), and few other available studies (42, ). In case of allergies or intolerance to chlorhexidine, some authors (, ), suggested the use of cetylpyridinium chloride or essential oils as possible alternatives.

To follow the advice found in publications regarding SARS-CoV-2 and dentistry, preoperative rinsing should be completed with a gargle. There is no consensus in the literature on the ideal duration of a gargle, which can range from 10 to 30 seconds.

It can be concluded that the use of pre-procedural mouth rinses must be considered beneficial and important for the reduction of the load of SARS-CoV-2 virus in saliva and aerosols generated by dental procedures. However, mouth rinses represent only a part of the measures which oral surgeons must adopt in preventing the spread of COVID-19, since rinses alone do not solve the infection of SARS-CoV-2 and do not prevent the spread of contagious diseases.

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Meister TL, Brüggemann Y, Todt D, Conzelmann C, Müller JA, Groß Ret al. Virucidal efficacy of different oral rinses against SARS-CoV-2. J Infect Dis. 2020 Jul 29:jiaa471.

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