Choosing the Appropriate Mask
The COVID-19 pandemic has seriously impacted dentistry. All oral health professionals are concerned about remaining safe during the provision of dental care and ensuring the safety of patients. The appropriate wearing of masks is key to the safe provision of care.
The COVID-19 pandemic has seriously impacted dentistry. All oral health professionals are concerned about remaining safe during the provision of dental care and ensuring the safety of patients. The appropriate wearing of masks is key to the safe provision of care.
The United States Centers for Disease Control and Prevention (CDC) released Interim Infection Prevention and Control Guidance for Dental Settings During the Coronavirus Disease 2019 (COVID-19) Pandemic, which it continues to update.1 This guidance recommends that all oral health professionals wear National Institute for Occupational Safety and Health (NIOSH)-approved N95 filtering facepiece respirators or higher in addition to a face shield or goggles. The document specifically advises:
- “Put on NIOSH-approved N95 filtering facepiece respirator or higher (use a facemask if a respirator is not available). If the respirator has a nosepiece, it should be fitted to the nose with both hands, not bent or tented. Do not pinch the nosepiece with one hand. Respirator/facemask should be extended under chin. Both your mouth and nose should be protected. Do not wear respirator/facemask under your chin or store in scrubs pocket between patients.
- Respirator: Respirator straps should be placed on crown of head (top strap) and base of neck (bottom strap). Perform a user seal check each time you put on the respirator.
- Facemask: Mask ties should be secured on crown of head (top tie) and base of neck (bottom tie). If mask has loops, hook them appropriately around your ears.
- Put on face shield or goggles. When wearing an N95 respirator or half facepiece elastomeric respirator, select the proper eye protection to ensure that the respirator does not interfere with the correct positioning of the eye protection, and the eye protection does not affect the fit or seal of the respirator. Face shields provide full face coverage. Goggles also provide excellent protection for eyes, but fogging is common.”2
The American Dental Association also recommends that oral health professionals wear full-face shields to ensure the safety of patients and dental team members.3
Understanding exactly what each type of mask does is helpful in building your knowledge of infection control protocol. The US Food and Drug Administration considers surgical face masks one-time use disposable medical devices.4 Masks are available ranging from minimum performance to maximum filtration depending on the task.5,6
The American Society for Testing and Materials Standards (ASTM) standard F2100-117 provides specifications for surgical face masks including bacterial filtration efficiency (BFE), submicron particulate filtration (PFE), delta P differential pressure, fluid resistance, and flammability.7 Molinari and Nelson state, “95% of dental aerosols are 5.0 microns or less in diameter and cannot be seen.”5 Masks with at least 95% BFE and PFE are preferable in the dental setting during aerosol-generating procedures. ASTM levels are classified into three levels of protection (low, moderate, high) to help clinicians decide which mask is appropriate for the task.
Currently, the use of N95 respirators is recommended for all clinical procedures. However, prior to the pandemic, Level 1 masks (low protection at ≥95% BFE and PFE) were suitable for brief examinations, exposing radiographs, and cleaning tasks.6 Level 2 masks (moderate protection at ≥98% BFE and PFE) were previously used for procedures that involved a moderate level of aerosols such as hand instrumentation and sealants and Level 3 masks, with a slightly higher level of protection (at ≥98% BFE and PFE), were recommended for procedures involving aerosols.6
Dentistry has done a great job of adhering to CDC guidelines since the 1980s. Revisions of evidence-based guidance are sure to come, but in the meantime, we need to follow best practices in safety.
REFERENCES
- United States Centers for Disease Control and Prevention. Guidance for Providing Dental Care During COVID-19. Available at: cdc.gov/oralhealth/infectioncontrol/statement-COVID.html. Accessed August 26, 2020.
- American Dental Association. CDC Guidance for Dental Settings Echoes ADA Guidance. Available at: ada.org/en/publications/ada-news/2020-archive/june/cdc-guidance-for-dental-settings-echoes-ada-guidance. Accessed August 26, 2020.
- United States Centers for Disease Control and Prevention. Using Personal Protective Equipment (PPE). Available at: cdc.gov/coronavirus/2019-ncov/hcp/using-ppe.html. Accessed August 26, 2020.
- United States Food and Drug Administration. Guidance for Industry and FDA Staff: Surgical Masks. Available at: fda.gov/medicaldevices/deviceregulationandguidance/guidancedocuments/ucm072549.htm. Accessed August 26, 2020.
- Molinari J, Nelson P. Face masks: what to wear and when. The Dental Advisor. 2014;10:14.
- Molinari J, Nelson P. Face Mask Performance: Are You Protected? Available at: medicom.com/uploads/files/Medicom%20Face%20Mask%20Performance%20Article_v3(1).pdf. Accessed August 25, 2020.
- American Society for Testing and Materials Standards (ASTM). ASTM F2100–11. Standard Specification for Performance of Materials Used in Medical Face Masks. Available at: astm.org/Standards/F2100.htm. Accessed August 26, 2020.
From Dimensions of Dental Hygiene. September 2020;18(8):46.
