Although the CDC does not have specific recommendations for using preprocedural antimicrobial mouthrinses to reduce aerosol exposure, studies show that their use for 60 seconds significantly reduces the level of oral microorganisms in the aerosols generated during routine dental procedures. 9,11,17,18,20
Full Answer
What microbes are aerosolized during dental procedures?
1. Using high volume evacuators and/or rubber dams greatly reduces aerosols (preferably both – as one can layer on protection with each intervention.) 2. Aerosols (versus spatter) are the big risk here. In a dental operatory, aerosols are produced and can linger in the air for 30 min. to 2 hours.
How can we reduce aerosol production during dental procedures?
Mar 01, 2018 · a study published in 2012 “showed that preprocedural rinse (chlorhexidine) and high-volume suction were effective when used alone as well as together in reducing the microbial load of the aerosols produced during ultrasonic scaling.”4 the authors reported “a significant reduction in the number of cfus in aerosol samples obtained.”4 a 1992 study …
Does mouthwash reduce the number of airborne bacteria during dental procedures?
Oct 01, 2000 · A combination of essential oils (eucalyptol, thymol, methyl salicylate, and menthol) in an alcohol base, essential-oil mouthrinses are thought to inhibit bacterial enzymes and reduce the pathogenicity of plaque. Several studies support their value in reducing bacteria in dental aerosols.
Are antimicrobial mouthrinses effective for reducing aerosol exposure?
Significant evidence suggests that using a large-bore capture device (≥8 mm diameter) on a properly functioning dental vacuum system removes 90% to 98% of any generated aerosol, preventing it from leaving the operative site. 13-18 The amount of aerosol capture via high-volume evacuation (HVE) is subject to the basic laws of air flow dynamics.
Reducing Risk of Aerosols
Dental patients can transmit viruses and bloodborne or respiratory pathogens through splatter, droplets, and aerosols to other patients and dental staff. 6 Ideally, such patients would refrain from proceeding with elective dental treatment until medically cleared, but individuals may be asymptomatic or simply unaware they are infected.
Role of Preprocedural Mouthrinsing
The goal of having patients rinse prior to beginning dental treatment is to reduce the bacterial load in the oral cavity.
Alternative Uses
Although most mouthrinses are used almost exclusively pre- and post-procedure, the investigation of alternative uses has emerged.
CONCLUSION
During the pandemic and after its conclusion, all infection control precautions should be maintained and executed at the highest level to not only protect the general public, but the oral health professionals serving at the forefront, as well.
What are the potential routes of infection in dental settings?
Potential routes of infection in dental settings are direct and indirect contact, inhalation, and injections/punctures. 9,13,31 These routes can be bidirectional where transmission may occur from patient-to-patient, patient-to-clinician, or clinician-to-patient. 24 Inhalation of bioaerosols is considered a moderate risk for disease transmission. 31 Dental patients and personnel are exposed to tens of thousands of bacteria per cubic meter, and the potential to breathe infective material that is aerosolized during routine dental procedures is highly likely. 13,30 Due to the size, composition, and ability to linger, airborne particles pose an increased health risk. 14,17,19,31
What are the bacteria that live in the oral cavity?
The oral cavity is inhabited by more than 700 bacterial species. It harbors fungi and viruses from the respiratory tract. 4,9,25 Temperature, pH, nutrients, host defenses, and host genetics contribute to microbial growth. 26,27 Many normal inhabitants of the oral cavity include species of Streptococcus, Actinomyces, Neisseria, Campylobacter, Porphyromonas, Prevotella, Capnocytophaga, and Fusobacteria. 5,21,26 The oral microenvironment can be altered by factors such as age, tooth eruption or loss, oral disease status, pregnancy, and drug use. Several of these changes can alter the virulence and pathogenicity of microorganisms. 27,28
Where do pathogens come from?
We know that pathogens come from two sources: the patient and dental unit water lines. We also know that aerosols, or tiny microdroplets, are created when we use instruments such as power scalers and air polishers. Aerosols are measured in microns. One millimeter is equal to 1,000 microns.
How much does HVE reduce particulates?
In a study published in 2002, Jacks found that a HVE device positioned extraorally within one inch of the commissure of the mouth resulted in reduction of particulates from 89.7% to 90.8% when compared to the intraorally positioned standard saliva ejector.
How does HVE work?
Several studies have shown that high-volume evacuation (HVE) devices work far better than saliva ejectors at controlling aerosols. A study published in the Journal of Dental Hygiene found that HVE devices can reduce aerosols by 89.7% to 90.8%.2 Most dental hygienists do not have the luxury of an assistant who can provide HVE while ...
Why do dentists use mouth rinses?
Mouthrinses are used in dentistry for a number of reasons: to freshen breath, to prevent or control tooth decay, to reduce plaque formation on teeth and gums, to prevent or reduce gingivitis, or to deliver a combination of these effects. Given their antiseptic properties, however, some agents also can serve an important function in infection ...
What is the purpose of mouth rinses?
A combination of essential oils (eucalyptol, thymol, methyl salicylate, and menthol) in an alcohol base, essential-oil mouthrinses are thought to inhibit bacterial enzymes and reduce the pathogenicity of plaque. Several studies support their value in reducing bacteria in dental aerosols.
Is chlorhexidine bactericidal or bacteriostatic?
Depending on dose. , the agent can be bactericidal or bacteriostatic.
Is chlorhexidine a cationic molecule?
A bisbiguanide with broad-spectrum antimicrobial activity, chlorhexidine is a symmetrical cationic molecule that binds strongly to hydroxylapatite, the organic pellicle of the tooth, oral mucosa, salivary proteins, and bacteria.
ABSTRACT
In light of the COVID-19 pandemic, it is essential that protocols be developed that enable ultrasonic therapy to be implemented with minimal risk to dental healthcare providers.
The Need for Periodontal Debridement
Adequate debridement is essential for periodontal inflammation to resolve. Persistence of inflammation in periodontal tissues contributes to the systemic burden of inflammation. 1 Low-grade systemic inflammation has the potential to increase the risk for subsequent infections.
The Extent of the Problem
Ultrasonic, compressed-air-driven high-speed handpieces, three-way water/air syringes, prophy cups/paste, and air-polishing devices all have the potential to generate aerosols, which can spread and persist if not adequately captured.
A Reasonable Approach Going Forward
For safe use of ultrasonic instrumentation, a layering of protections has long been suggested.
N-95 Respirators
Certainly, the use of a surgical N-95 respirator is preferable. However, data is sorely lacking regarding the effectiveness of these respirators, level 3 masks, and face shields used either alone or in combination during procedures and their potential to protect against viral-laden aerosols.
Conclusion
It is important for dental professionals to perform risk assessments to determine what is safe and effective for themselves and their patients before proceeding with treatment.
About the Authors
Timothy Donley, DDS, MSD#N#Private Practice specializing in Periodontics, Bowling Green, Kentucky; Co-author, Ultrasonic Periodontal Debridement: Theory and Technique
How to reduce aerosol production?
Here is a new process to follow to reduce aerosol production while using ultrasonic instruments: Check the instructions on the package insert for your chosen tip for the recommended power levels. Use the appropriate power level range. Tips recommended for low-to-medium power should not be used on higher power levels.
What is an oral evacuator?
Two types of oral evacuators are used to remove liquid and debris from the mouth during dental procedures: saliva ejectors used with low-volume evacuation (LVE) systems and high-volume (HVE) systems – each generally used with single-use/disposable tips. Studies show that the bores of saliva ejectors are too small to remove aerosols ...
How to use ultrasonic?
Here is a new process to follow to reduce aerosol production while using ultrasonic instruments: 1 Check the instructions on the package insert for your chosen tip for the recommended power levels. 2 Use the appropriate power level range. Tips recommended for low-to-medium power should not be used on higher power levels. 3 Set water flow to a rapid drip (three drips per second) or a slow stream. The water flow rate should be 20 milliliters per minute. (You can test water flow rate using a small beaker and a timer.)
How long do dental aerosols stay in the air?
In a dental operatory, aerosols are produced and can linger in the air for 30 min. to 2 hours . (an argument for using “new” rooms after patient care – and waiting 2 hours to clean the previous room to allow aerosols from previous patient care to settle out)
What is the biggest concern in dentistry?
Aerosols (the big concern): particles less than 50 μm in diameter. Particles of this size are small enough to stay airborne for an extended period before they settle on environmental surfaces or enter the respiratory tract. The smaller particles of an aerosol (0.5 to 10 μm in diameter) have the potential to penetrate and lodge in the smaller passages of the lungs and are thought to carry the greatest potential for transmitting infections. The greatest airborne infection threat in dentistry comes from aerosols
What is the greatest threat to dentistry?
The greatest airborne infection threat in dentistry comes from aerosols.
What is a splatter?
Splatter (less of a concern): Airborne particles larger than 50 μm in diameter. These particles behaved in a ballistic manner. This means that these particles or droplets are ejected forcibly from the operating site and arc in a trajectory similar to that of a bullet until they contact a surface or fall to the floor.
What are the sources of airborne contamination?
There are at least three potential sources of airborne contamination during dental treatment: dental instrumentation, saliva, and respiratory sources, and the operative site. Most dental procedures that use mechanical instrumentation will produce airborne particles from the site where the instrument is used.
How long do droplets stay in the air?
Droplet nuclei can contaminate surfaces in a range of three feet and may remain airborne for 30 minutes to two hours.
Do N95 masks protect against aerosols?
(Another argument for new room use) Traditional masks only seem to work for splatter. They do not protect against aerosols. N95 masks require fitting to work properly.
Reducing Risk of Aerosols
Role of Preprocedural Mouthrinsing
- The goal of having patients rinse prior to beginning dental treatment is to reduce the bacterial load in the oral cavity. While there is no evidence supporting the effectiveness of preprocedural mouthrinsing in the prevention of SARS-COV-2, the ability of some therapeutic ingredients to decrease transmission of pathogens suggests there may be effic...
Alternative Uses
- Although most mouthrinses are used almost exclusively pre- and post-procedure, the investigation of alternative uses has emerged. When it comes to essential oils, preprocedural rinsing used in conjunction with preprocedural subgingival irrigation has proven to significantly decrease the level of bacteremia associated with subgingival ultrasonic scaling.2 Moreover, as …
Conclusion
- During the pandemic and after its conclusion, all infection control precautions should be maintained and executed at the highest level to not only protect the general public, but the oral health professionals serving at the forefront, as well. The use of a simple antimicrobial preprocedural mouthrinse can help promote a safe work environment and reduce the transmissi…
References
- Narayana TV, Mohanty L, Sreenath G, Vidhyadhari P. Role of preprocedural rinse and high volume evacuator in reducing bacterial contamination in bioaerosols. J Oral Maxillofac Pathol. 2016;20:59–65.
- Walsh LJ. Antiviral and antibacterial effects of preprocedural mouthrinses. Australasian Dental Practice. 2011;22(4):112–118.
- Narayana TV, Mohanty L, Sreenath G, Vidhyadhari P. Role of preprocedural rinse and high volume evacuator in reducing bacterial contamination in bioaerosols. J Oral Maxillofac Pathol. 2016;20:59–65.
- Walsh LJ. Antiviral and antibacterial effects of preprocedural mouthrinses. Australasian Dental Practice. 2011;22(4):112–118.
- Akanksha S, Shiva Manjunath RG, Deepak S, et al. Aerosol, a health hazard during ultrasonic scaling: a clinico-microbiological study. Indian J Dent Res. 2016;27:160–162.
- Saini R. Efficacy of preprocedural mouth rinse containing chlorine dioxide in reduction of viable bacterial count in dental aerosols during ultrasonic scaling: a double-blind, placebo-controlled cl...
Associated Respiratory Infections
Aerosol Production
- Potential routes of infection in dental settings are direct and indirect contact, inhalation, and injections/punctures.9,13,31 These routes can be bidirectional where transmission may occur from patient-to-patient, patient-to-clinician, or clinician-to-patient.24 Inhalation of bioaerosols is considered a moderate risk for disease transmission.31 Dental patients and personnel are expo…
Aerosol Prevention and Reduction
- Many safety procedures should be incorporated into daily practice to minimize aerosol production, prevent contamination from emitted particles, and reduce transmission of infectious diseases. Minimizing dissemination of aerosols can be accomplished through the use of high velocity air evacuation and preprocedural antimicrobial mouthrinses, flushing...
Conclusion
- Patients and oral health professionals are regularly exposed to tens of thousands of aerosols generated during dental procedures.30 This exposure increases the risk of respiratory infections.24,30 To ensure safety and reduce risk of respiratory infections, oral health professionals should abide by current CDC guidelines and recommendations. This includes usin…
References
- World Health Organization. The Top 10 Causes of Death. Available at:who.int/news-room/fact-sheets/detail/the-top-10-causes-of-death. Accessed September 28, 2018.
- GBD 2015 LRI Collaborators. Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory tract infections in 195 countries: a systematic analysis for t...
- World Health Organization. The Top 10 Causes of Death. Available at:who.int/news-room/fact-sheets/detail/the-top-10-causes-of-death. Accessed September 28, 2018.
- GBD 2015 LRI Collaborators. Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory tract infections in 195 countries: a systematic analysis for t...
- Murphy SL, Xu J, Kochanek KD, Curtin SC, Arias E. Deaths: final data for 2015. Natl Vital Stat Rep. 2017;66:1–75
- Aas JA, Paster BJ, Stokes LN, Olsen I, Dewhirst FE. Defining the normal bacterial flora of the oral cavity. J Clin Microbiol. 2005;43(11):5721-5732.