Guidance for Dental Settings

Background

This interim guidance has been updated based on currently available information about coronavirus disease 2019 (COVID-19) and the current situation in the United States. As dental healthcare facilities begin to restart elective procedures in accordance with guidance from local and state officials, there are precautions that should remain in place as a part of the ongoing response to the COVID-19 pandemic. Most recommendations in this updated guidance are not new (except as noted in the summary of changes above); they have been reorganized into the following sections:

1. Recommended infection prevention and control (IPC) practices for routine dental healthcare delivery during the pandemic
2. Recommended IPC practices when providing dental healthcare for a patient with suspected or confirmed SARS-CoV-2 infection

Dental settings should balance the need to provide necessary services while minimizing risk to patients and dental healthcare personnel (DHCP). CDC has developed a framework for healthcare personnel and healthcare systems for delivery of non-emergent care during the COVID-19 pandemic. DHCP should regularly consult their state dental boards and state or local health departments for current local information for requirements specific to their jurisdictions, including recognizing the degree of community transmission and impact, and their region-specific recommendations.

Transmission: SARS-CoV-2, the virus that causes COVID-19, is thought to spread primarily between people who are in close contact with one another (within 6 feet) through respiratory droplets produced when an infected person coughs, sneezes, or talks. Airborne transmission from person-to-person over long distances is unlikely. However, COVID-19 is a new disease, and we are still learning about how the virus spreads and the severity of illness it causes. The virus has been shown to persist in aerosols for hours, and on some surfaces for days under laboratory conditions. SARS-CoV-2 can be spread by people who are not showing symptoms.

Risk: The practice of dentistry involves the use of rotary dental and surgical instruments, such as handpieces or ultrasonic scalers and air-water syringes. These instruments create a visible spray that can contain particle droplets of water, saliva, blood, microorganisms, and other debris. Surgical masks protect mucous membranes of the mouth and nose from droplet spatter, but they do not provide complete protection against inhalation of infectious agents. There are currently no data available to assess the risk of SARS-CoV-2 transmission during dental practice.

Recommendations

1. Recommended infection prevention and control (IPC) practices for routine dental healthcare delivery during the pandemic

CDC recommends using additional infection prevention and control practices during the COVID-19 pandemic, along with standard practices recommended as a part of routine dental healthcare delivery to all patients. These practices are intended to apply to all patients, not just those with suspected or confirmed SARS-CoV-2 infection (See Section 2 for additional practices that should be used when providing dental healthcare for patients with suspected or confirmed SARS-CoV-2 infection). These additional practices for all patients include:

PPE Supply Optimization Strategies

Major distributors in the United States have reported shortages of PPE, especially surgical masks and respirators. The anticipated timeline for return to routine levels of PPE is not yet known. CDC has developed a series of strategies or options to optimize supplies of PPE in healthcare settings when there is limited supply, and a burn rate calculator that provides information for healthcare facilities to plan and optimize the use of PPE for response to the COVID-19 pandemic. Optimization strategies are provided for gloves, gowns, facemasks, eye protection, and respirators.

These policies are only intended to remain in effect during times of shortages during the COVID-19 pandemic. DHCP should review this guidance carefully, as it is based on a set of tiered recommendations. Strategies should be implemented sequentially. Decisions by facilities to move to contingency and crisis capacity strategies are based on the following assumptions:

• Facilities understand their current PPE inventory and supply chain;
• Facilities understand their PPE utilization rate;
• Facilities are in communication with local healthcare coalitions and federal, state, and local public health partners (e.g., public health emergency preparedness and response staff) regarding identification of additional supplies;
• Facilities have already implemented engineering and administrative control measures;
• Facilities have provided DHCP with required education and training, including having them demonstrate competency with donning and doffing, with any PPE ensemble that is used to perform job responsibilities, such as provision of patient care.

For example, extended use of facemasks and respirators should only be undertaken when the facility is at contingency or crisis capacity and has reasonably implemented all applicable administrative and engineering controls. Such controls include selectively canceling elective and non-urgent procedures and appointments for which PPE is typically used by DHCP. Extended use of PPE is not intended to encourage dental facilities to practice at a normal patient volume during a PPE shortage, but only to be implemented in the short term when other controls have been exhausted. Once the supply of PPE has increased, facilities should return to conventional strategies.

Respirators that comply with international standards may be considered during times of known shortages. CDC has guidance entitled Factors to Consider When Planning to Purchase Respirators from Another Country which includes a webinar, and Assessments of International Respirators.

Hand Hygiene

Ensure DHCP practice strict adherence to hand hygiene, including:

• Before and after all patient contact, contact with potentially infectious material, and before putting on and after removing personal protective equipment (PPE), including gloves. Hand hygiene after removing PPE is particularly important to remove any pathogens that might have been transferred to bare hands during the removal process.
• Use ABHR with at least 60% alcohol or wash hands with soap and water for at least 20 seconds. If hands are visibly soiled, use soap and water before returning to ABHR.
• Dental healthcare facilities should ensure that hand hygiene supplies are readily available to all DHCP in every patient care location.

Equipment Considerations

• After a period of non-use, dental equipment may require maintenance and/or repair. Review the manufacturer’s instructions for use (IFU) for office closure, period of non-use, and reopening for all equipment and devices. Some considerations include:
  • Dental unit waterlines (DUWL):
    • Test water quality to ensure it meets standards for safe drinking water as established by the Environmental Protection Agency (< 500 CFU/mL) prior to expanding dental care practices.
    • Confer with the manufacturer regarding recommendations for need to shock DUWL of any devices and products that deliver water used for dental procedures.
    • Continue standard maintenance and monitoring of DUWL according to the IFUs of the dental operatory unit and the DUWL treatment products.
  • Autoclaves and instrument cleaning equipment
    • Ensure that all routine cleaning and maintenance have been performed according to the schedule recommended per manufacturer’s IFU.
    • Test sterilizers using a biological indicator with a matching control (i.e., biological indicator and control from same lot number) after a period of non-use prior to reopening per manufacturer’s IFU.
  • Air compressor, vacuum and suction lines, radiography equipment, high-tech equipment, amalgam separators, and other dental equipment: Follow protocol for storage and recommended maintenance per manufacturer IFU.
• For additional guidance on reopening buildings, see CDC’s Guidance for Reopening Buildings After Prolonged Shutdown or Reduced Operation.

Optimize the Use of Engineering Controls

CDC does not provide guidance on the decontamination of building heating, ventilation, and air conditioning (HVAC) systems potentially exposed to SARS-CoV-2. To date, CDC has not identified confirmatory evidence to demonstrate that viable virus is contaminating these systems. CDC provides the following recommendations for proper maintenance of ventilation systems and patient placement and volume strategies in dental settings.

• Properly maintain ventilation systems.
  • Ventilation systems that provide air movement in a clean-to-less-clean flow direction reduce the distribution of contaminants and are better at protecting staff and patients. For example, in a dental facility with staff workstations in the corridor right outside the patient operatories, supply-air vents would deliver clean air into the corridor, and return-air vents in the rear of the less-clean patient operatories would pull the air out of the room. Thus, the clean air from the corridor flows past the staff workstations and into the patient operatories. Similarly, placing supply-air vents in the receptionist area and return-air vents in the waiting area pulls clean air from the reception area into the waiting area.
  • Consult with facilities operation staff or an HVAC professional to
    • Understand clinical air flow patterns and determine air changes per hour.
    • Investigate increasing filtration efficiency to the highest level compatible with the HVAC system without significant deviation from designed airflow.
    • Investigate the ability to safely increase the percentage of outdoor air supplied through the HVAC system (requires compatibility with equipment capacity and environmental conditions).
  • Limit the use of demand-controlled ventilation (triggered by temperature setpoint and/or by occupancy controls) during occupied hours and when feasible, up to 2 hours post occupancy to assure that the ventilation rate does not automatically change. Run bathroom exhaust fans continuously during business hours.
  • Consider the use of a portable high-efficiency particulate air (HEPA) air filtration unit while the patient is undergoing, and immediately following, an aerosol generating procedure.
    • Select a HEPA air filtration unit based on its Clean Air Delivery Rate (CADR). The CADR is an established performance standard defined by the Association of Home Appliance Manufacturers and reports the system’s cubic feet per minute (CFM) rating under as-used conditions. The higher the CADR, the faster the air cleaner will work to remove aerosols from the air.
    • Rather than just relying on the building’s HVAC system capacity, use a HEPA air filtration unit to reduce aerosol concentrations in the room and increase the effectiveness of the turnover time.
    • Place the HEPA unit near the patient’s chair, but not behind the DHCP. Ensure the DHCP are not positioned between the unit and the patient’s mouth. Position the unit to ensure that it does not pull air into or past the breathing zone of the DHCP.
  • Consider the use of upper-room ultraviolet germicidal irradiation (UVGI) as an adjunct to higher ventilation and air cleaning rates.

• Patient placement
  • Ideally, dental treatment should be provided in individual patient rooms, whenever possible.
  • For dental facilities with open floor plans, to prevent the spread of pathogens there should be:
    • At least 6 feet of space between patient chairs.
    • Physical barriers between patient chairs. Easy-to-clean floor-to-ceiling barriers will enhance effectiveness of portable HEPA air filtration systems (check to make sure that extending barriers to the ceiling will not interfere with fire sprinkler systems).
    • Operatories should be oriented parallel to the direction of airflow if possible.
  • Where feasible, consider patient orientation carefully, placing the patient’s head near the return air vents, away from pedestrian corridors, and toward the rear wall when using vestibule-type office layouts.

• Patient volume
  • Ensure to account for the time required to clean and disinfect operatories between patients when calculating your daily patient volume.

Environmental Infection Control

• DHCP should ensure that environmental cleaning and disinfection procedures are followed consistently and correctly after each patient (however, it is not necessary that DHCP should attempt to sterilize a dental operatory between patients).
  • Clean and disinfect the room and equipment according to the Guidelines for Infection Control in Dental Health-Care Settings—2003pdf icon.

• Routine cleaning and disinfection procedures (e.g., using cleaners and water to clean surfaces before applying an Environmental Protection Agency (EPA)-registered, hospital-grade disinfectant to frequently touched surfaces or objects for appropriate contact times as indicated on the product’s label) are appropriate for SARS-CoV-2 in healthcare settings, including those patient-care areas in which aerosol generating procedures are performed.
  • Refer to List Nexternal icon on the EPA website for EPA-registered disinfectants that have qualified under EPA’s emerging viral pathogens program for use against SARS-CoV-2.
• Alternative disinfection methods
  • The efficacy of alternative disinfection methods, such as ultrasonic waves, high intensity UV radiation, and LED blue light against SARS-CoV-2 virus is not known. EPA does not routinely review the safety or efficacy of pesticidal devices, such as UV lights, LED lights, or ultrasonic devices. Therefore, EPA cannot confirm whether, or under what circumstances, such products might be effective against the spread of COVID-19.
  • CDC does not recommend the use of sanitizing tunnels. There is no evidence that they are effective in reducing the spread of COVID-19. Chemicals used in sanitizing tunnels could cause skin, eye, or respiratory irritation or damage.
  • EPA only recommends use of the surface disinfectants identified on List Nexternal icon against the virus that causes COVID-19.
• Manage laundry and medical waste in accordance with routine policies and procedures.

Sterilization and Disinfection of Patient-Care Items

• Sterilization protocols do not vary for respiratory pathogens. DHCP should perform routine cleaning, disinfection, and sterilization protocols, and follow the recommendations for Sterilization and Disinfection of Patient-Care Items present in the Guidelines for Infection Control in Dental Health Care Settings – 2003pdf icon.
• DHCP should follow the manufacturer’s instructions for times and temperatures recommended for sterilization of specific dental devices.

Education and Training

• Provide DHCP with job- or task-specific education and training on preventing transmission of infectious agents, including refresher training.
  • Training: Basic Expectations for Safe Care
• Ensure that DHCP are educated, trained, and have practiced the appropriate use of PPE prior to caring for a patient, including attention to correct use of PPE and prevention of contamination of clothing, skin, and the environment during the process of removing such equipment.
  • Using Personal Protective Equipment (PPE)
  • Healthcare Respiratory Protection Resources Training

2. Recommended infection prevention and control (IPC) practices when providing dental healthcare for a patient with suspected or confirmed SARS-CoV-2 infection

Surgical procedures that might pose higher risk for SARS-CoV-2 transmission if the patient has COVID-19 include those that generate potentially infectious aerosols or involve anatomic regions where viral loads might be higher, such as the nose and throat, oropharynx, respiratory tract (see Surgical FAQ).

• If a patient arrives at your facility and is suspected or confirmed to have COVID-19, defer non-emergent dental treatment and take the following actions:
  • If the patient is not already wearing a cloth face covering, give the patient a facemask to cover his or her nose and mouth.
  • If the patient is not manifesting emergency warning signs for COVID-19, send the patient home, and instruct the patient to call his or her primary care provider.
  • If the patient is manifesting emergency warning signs for COVID-19 (for example, has trouble breathing), refer the patient to a medical facility, or call 911 as needed and inform them that the patient may have COVID-19.
• If emergency dental care is medically necessary for a patient who has, or is suspected of having, COVID-19, DHCP should follow CDC’s Interim Infection Prevention and Control Recommendations for Healthcare Personnel During the Coronavirus Disease 2019 (COVID-19) Pandemic.
• Dental treatment should be provided in an individual patient room with a closed door.
• DHCP who enter the room of a patient with suspected or confirmed SARS-CoV-2 infection should adhere to Standard Precautions and use a NIOSH-approved N95 or equivalent or higher-level respirator (or facemask if a respirator is not available), gown, gloves, and eye protection. Protective eyewear (e.g., safety glasses, trauma glasses) with gaps between glasses and the face likely do not protect eyes from all splashes and sprays.
  • Avoid aerosol generating procedures (e.g., use of dental handpieces, air/water syringe, ultrasonic scalers) if possible.
  • If aerosol generating procedures must be performed
    • Aerosol generating procedures should ideally take place in an airborne infection isolation room.
    • DHCP in the room should wear an N95 or equivalent or higher-level respirator, such as disposable filtering facepiece respirator, PAPR, or elastomeric respirator, as well as eye protection (goggles or a face shield that covers the front and sides of the face), gloves, and a gown.
    • The number of DHCP present during the procedure should be limited to only those essential for patient care and procedure support. Visitors should not be present for the procedure.
    • Clean and disinfect procedure room surfaces promptly as described in the section on environmental infection control.
  • Limit transport and movement of the patient outside of the room to medically essential purposes.
    • Patients should wear a facemask or cloth face covering to contain secretions during transport. If patients cannot tolerate a facemask or cloth face covering or one is not available, they should use tissues to cover their mouth and nose while out of their room or care area.
  • Consider scheduling the patient at the end of the day.
  • Do not schedule any other patients at that time.
• To clean and disinfect the dental operatory after a patient with suspected or confirmed COVID-19, DHCP should delay entry into the operatory until a sufficient time has elapsed for enough air changes to remove potentially infectious particles. CDC’s Guidelines for Environmental Infection Control in Health-Care Facilities (2003) provides a table to calculate time required for airborne-contaminant removal by efficiency.

Definitions

Aerosol generating procedures – Procedures that may generate aerosols (i.e., particles of respirable size, <10 μm). Aerosols can remain airborne for extended periods and can be inhaled. Development of a comprehensive list of aerosol generating procedures for dental healthcare settings has not been possible, due to limitations in available data on which procedures may generate potentially infectious aerosols and the challenges in determining their potential for infectivity. There is neither expert consensus, nor sufficient supporting data, to create a definitive and comprehensive list of aerosol generating procedures for dental healthcare settings. Commonly used dental equipment known to create aerosols and airborne contamination include ultrasonic scaler, high-speed dental handpiece, air/water syringe, air polishing, and air abrasion.

Airborne infection isolation rooms – Single-patient rooms at negative pressure relative to the surrounding areas, and with a minimum of 6 air changes per hour (12 air changes per hour are recommended for new construction or renovation). Air from these rooms should be exhausted directly to the outside or be filtered through a high-efficiency particulate air (HEPA) filter directly before recirculation. Room doors should be kept closed except when entering or leaving the room, and entry and exit should be minimized. Facilities should monitor and document the proper negative-pressure function of these rooms.

Air changes per hour: the ratio of the volume of air flowing through a space in a certain period of time (the airflow rate) to the volume of that space (the room volume). This ratio is expressed as the number of air changes per hour.

Cloth face covering: Textile (cloth) covers that are intended for source control. They are not personal protective equipment (PPE) and it is uncertain whether cloth face coverings protect the wearer.

Community Transmission

• No to minimal community transmission: Evidence of isolated cases or limited community transmission, case investigations underway; no evidence of exposure in large communal setting
• Minimal to moderate community transmission: Sustained transmission with high likelihood or confirmed exposure within communal settings and potential for rapid increase in cases
• Substantial community transmission: Large scale community transmission, including communal settings (e.g., schools, workplaces)

Dental healthcare personnel (DHCP) – Refers to all paid and unpaid persons serving in dental healthcare settings who have the potential for direct or indirect exposure to patients or infectious materials, including:

• body substances
• contaminated medical supplies, devices, and equipment
• contaminated environmental surfaces
• contaminated air

Facemaskpdf icon: Facemasks are PPE and are often referred to as surgical masks or procedure masks. Use facemasks according to product labeling and local, state, and federal requirements. FDA-cleared surgical masks are preferred in dental settings because they are designed to protect against splashes and sprays and are prioritized for use when such exposures are anticipated, including surgical procedures. Facemasks that are not regulated by FDA, such as some procedure masks, which are typically used for isolation purposes, may not provide protection against splashes and sprays.

Respirator: Is a personal protective device that is worn on the face, covers at least the nose and mouth, and is used to reduce the wearer’s risk of inhaling hazardous airborne particles (including dust particles and infectious agents), gases, or vapors. Respirators are certified by CDC/National Institute for Occupational Safety and Health (NIOSH), including those intended for use in healthcare.

Respirator use must be in the context of a complete respiratory protection program in accordance with OSHA Respiratory Protection standard (29 CFR 1910.134external icon). DHCP should be medically cleared and fit tested if using respirators with tight-fitting facepieces (e.g., a NIOSH-approved N95 respirator) and trained in the proper use of respirators, safe removal and disposal, and medical contraindications to respirator use.