Splatter and aerosols are inevitably generated during the course of dental healthcare delivery. There is concern that infectious material may be transmitted through splatter and aerosols. Studies show that splatter and aerosol generation is greatest with the use of ultrasonic scalers, air/water syringes and dental handpieces.
Aerosols are defined as solid or liquid particles that are 50 μm or less in diameter. They are invisible to the naked eye. These aerosol particles can remain suspended in air for several hours and reach and can be transferred from clinical to non clinical areas through air movement. They may be inhaled by the DHCP and reach the alveoli of the lung. Splatter is described as a mixture of air, water and solid substances greater than 50 μm and is visible to the naked eye. These particles may act as projectiles that may settle on environmental or bodily surfaces. These splatter particles can be projected in several trajectories to distances of 15 cm to 120 cm. A biofilm is a complex aggregation of microorganisms growing on a solid substrate. Dental plaque is a biofilm that acts as a substrate for colony forming organisms. In addition the biofilm provides a medium of communication between microorganisms. The biofilm may provide protection for the microbial organisms against destruction.
While it is well known that preprocedural mouth rinsing with chlorhexidine, essential oils and povidone iodine result in reduced bacterial counts, it may be equally beneficial to perform preprocedural brushing and flossing in order to physically disturb the biofilm formation. These practices may help render bacteria to increased exposure to antimicrobial agents which in turn result in increased destruction.
However, a brushing and flossing regimen is apparently insufficient to control biofilm. Mouth rinsing is primarily performed by persons to reduce oral malodor or halitosis. Including an antimicrobial mouth rinse to the regimen would complement brushing and flossing. Brush, floss and rinse (BFR) should be the standard for whole mouth cleansing. Dental biofilm immediately re-establishes itself after disruption.
Bacteria from the biofilm on mucosal and tooth surfaces are shed constantly into saliva and transferred to other areas of the mouth. Oral mucosa makes up approximately 80% of the oral cavity surface and can serve as a reservoir for pathogenic bacteria. These bacteria can be transferred to the tooth surface and gingival sulcus. Adjunctive use of antibacterial mouth rinse with mechanical biofilm control measures may play an important role in reducing reservoirs of pathogens that may cause oral disease.
No scientific evidence indicates that preprocedural mouth rinsing prevents clinical infections among DHCP or patients, but studies have demonstrated that a preprocedural rinse with an antimicrobial product (eg, chlorhexidine gluconate, essential oils or povidone-iodine) can reduce the level of oral microorganisms in aerosols and spatter generated during routine dental procedures with rotary instruments (eg, dental handpieces or ultrasonic scalers). Preprocedural mouth rinses can be most beneficial before a procedure that requires using a prophylaxis cup or ultrasonic scaler because rubber dams cannot be used to minimize aerosol and spatter generation and, unless the provider has an assistant, high volume evacuation is not commonly used.
The science is unclear concerning the incidence and nature of bacteremias from oral procedures, the relationship of these bacteremias to disease, and the preventive benefit of antimicrobial rinses. In limited studies, no substantial benefit has been demonstrated for mouth rinsing in terms of reducing oral microorganisms in dental-induced bacteremias. However, the American Heart Association’s recommendations regarding preventing bacterial endocarditis during dental procedure provide limited support concerning preprocedural mouth rinsing with an antimicrobial as an adjunct for patients at risk for bacterial endocarditis. Insufficient data exist to recommend preprocedural mouth rinses to prevent clinical infections among patients or DHCP.
Preprocedural Mouth Rinses
No recommendation is offered regarding use of preprocedural antimicrobial mouth rinses to prevent clinical infections among DHCP or patients. Although studies have demonstrated that a preprocedural antimicrobial rinse (eg, chlorhexidine gluconate, essential oils or povidone-iodine) can reduce the level of oral microorganisms in aerosols and spatter generated during routine dental procedures and can decrease the number of microorganisms introduced in the patient’s bloodstream during invasive dental procedures, the scientific evidence is inconclusive that using these rinses prevent clinical infections among DHCP or patients (see discussion, Preprocedural Mouth Rinses)
While this is still an unresolved issue it may be prudent to adopt brush, floss and rinse practices until the issue is finally resolved.