The Crucial Role of PPE in Infection Control

A comprehensive knowledge of infection control and prevention is crucial for all oral health professionals when seeking to safeguard themselves, their patients, and colleagues from potential disease transmission. Personal protective equipment (PPE) — such as masks, gloves, protective eyewear, shields, and disposable lab coats — are essential aspects of infection prevention and control for all clinical members of the dental team. Understanding and reviewing the role of PPE will enable the dental hygienist to use it appropriately while ensuring that safety and the hygienist/​patient relationship remain central to care. The use of PPE requires appropriate selection, application, and effective assessment for each patient interaction.

As dental healthcare professionals, the risk of exposure to bloodborne pathogens and infectious respiratory diseases is a significant concern. Dental hygienists, in particular, face an increased risk because they perform procedures that produce aerosols.¹ To ensure their safety, these professionals must wear appropriate PPE and adhere to standard precautions.² This is especially essential during procedures that may result in blood or bioaerosols splashing or spattering. Procedures that release particles smaller than 5 μm from the respiratory tract into the air are known as aerosol-producing procedures.³

In the past 3 years, the SARS-CoV-2 virus has highlighted the risk of respiratory infections. Nevertheless, oral health professionals should be aware of any viruses that pose a potential exposure to respiratory diseases. Infection prevention starts with screening patients for any symptoms of respiratory illness.^2,4

Risk of Aerosol Exposure

Recent studies have investigated the spread of aerosols and airborne contamination during dental procedures, particularly their ability to travel long distances. The objective is to determine the level of infectivity from aerosols and spatter in a dental environment.⁵ Oral health professionals, especially dental hygienists, must consider when and how to evaluate potential aerosol exposure and select the appropriate PPE. When evaluating potential aerosol exposure, three sources should be examined.³ According to a study by Dudding et al,³ the first source of aerosol production is the host, or patient. This is generated by breathing, speaking, and, in some cases, coughing during the provision of care and when in close proximity to the patient.^3,6

The second source of aerosols is generated by instruments, which are not contaminated prior to them being used on a patient.^3,6 An example of aerosols generated by noncontaminated instruments would be the activation of the ultrasonic scaler or slow-speed handpiece before its used in the oral cavity.

Lastly, aerosols generated by the activation of the instrument in the patient’s oral cavity are considered contaminated by saliva and or blood. This activity, as well as a patient coughing during treatment, poses an occupational hazard to dental hygienists.^3,6

Protective Eyewear

To ensure their safety, dental hygienists should wear eye protection and face shields. All employers must adhere to the health and safety regulations set by the Occupational Safety and Health Administration (OSHA), which includes the use of PPE such as goggles and face shields.^1,7,8 Goggles are the standard for eye protection, and the United States Centers for Disease Control and Prevention (CDC) advises against using personal prescription lenses instead of goggles, as they do not provide adequate eye protection. Goggles need to fit tightly over personal prescription lenses and cover the eyes completely. Goggles with anti-fog features for clear vision are also recommended.^4,8

Face Shields

Face shields safeguard the entire face, including the eyes, nose, mouth, and forehead. To ensure complete protection, the shield must wrap around the sides of the face and extend below the chin. During dental procedures, patients who cough pose a greater risk of spreading viruses than aerosol-producing procedures.⁷ This is because coughing generates much higher aerosol number concentrations than most aerosol-producing procedures.³ For dental hygienists, using only a face shield is not sufficient; it offers some protection as it can safeguard against direct splashes and droplets.^8,9 The use of both face shields and eye goggles can improve protection. This will minimize the risk of exposure to bloodborne pathogens and infectious respiratory diseases.^10,11

Protective Clothing/​Gowns

Dental hygiene procedures usually include using equipment, such as ultrasonic scalers and slow-speed devices, and delivering nonsurgical periodontal treatment. These procedures can produce bioaerosols and spatter, which involves saliva and blood.⁹ To address this concern,OSHA requires the wearing of protective clothing, such as gowns, lab coats, or aprons, to prevent the transfer of microorganisms, body fluids, and other materials. Isolation gowns specifically must cover the arms, torso, and clothing — serving as a physical barrier against biohazard materials.¹²

For optimal safety, oral health professionals should wear disposable gowns with long sleeves and high necks in addition to their usual work attire.¹³ Clinical scrubs, which usually feature short sleeves and low necks, do not provide adequate protection.¹⁴ Protective clothing should be changed at least once a day, such as during lunchtime, or more frequently if visibly soiled during routine dental procedures.^1,4,15

Reusable protective clothing, such as lab coats, long-sleeved scrub tops, and scrub uniforms, must be managed correctly according to Organization for Safety, Asepsis and Prevention (OSAP) guidelines and OSHA regulations. Employers are required to ensure that all PPE, including protective clothing, is maintained, cleaned, laundered, and disposed of at no cost to their employees.⁷ To ensure safety, employees should not wash protective clothing at home.^7,14 Instead, employers should provide either disposable protective clothing or reusable protective clothing that can be washed on-site or by a laundry service.¹⁵

Head and Shoe Covers

Although shoe covers and head covers are considered PPE, they are not frequently used in most dental practices. The use of head and shoe covers is not mandated by OSHA for use in dentistry, but they should be considered if the chance of contamination is anticipated.¹⁶ Head covers may be indicated for patient protection when working in a sterile field as well as for hygienic reasons, therefore a complete risk assessment should be conducted prior to patient care to determine proper PPE selection.^16,17

Although no quantitative evidence exists, head covers have gained popularity in dentistry since the COVID-19 pandemic. They are optional but may be beneficial in reducing contamination of the dental professional’s head when spraying and spattering of potentially infectious material or blood is anticipated. There is, however, a lack of evidence to indicate that disease transmission can occur due to hair contamination.

A study conducted by Chanpong et al¹⁰ showed that a single simulated cough can contaminate the crown of the head, back, and shoes of the dental professional. The presence of these contaminants could lead to self-contamination when doffing PPE. This limited evidence suggests that it may be beneficial to wear surgical caps/​bouffants and shoe coverings to prevent cross contamination between patients and dental practitioners.

Masks

Scientific evidence clearly demonstrates that the proper use of appropriate masks is a critical factor in reducing the spread of viral infections during patient care.¹⁸ Before choosing a mask, the level of protection needed by the dental professional must be examined. A surgical mask offers protection against diseases transmitted by droplets. The distinguishing feature of a respirator or N95 mask is that it protects against diseases transmitted by aerosols.¹⁹

A well-fitting surgical mask must be properly secured with no gaps around the seal of the mask or on the side near the ears or below the chin. It should fit comfortably for the entire duration of the dental hygiene appointment. The style and shape of the mask should be a matter of preference for the dental hygienist, as wearing ear loops can be irritating if worn for long periods of time.¹⁴ The discomfort of wearing respirators or N95 masks in the healthcare setting may inhibit dental professionals from closely following proper usage protocols, decreasing their efficacy. If an N95 or respirator is required, it must always first be fit tested to ensure its effectiveness.^14,18,19

Gloves

The use of gloves is considered the most important barrier to the transmission of disease in dentistry.^20,21 They protect both the dental professional and the patient during dental procedures. Gloves are identified as medical devices by the US Food and Drug Administration. Certain performance standards must be met, including tear-resistance and permeability.

Gloves can be classified as patient care gloves or nonpatient care (utility) gloves.^20,21 Patient care gloves are used for all dental treatments that involve intraoral contact; however, oral surgery procedures require the use of sterile surgical gloves. When choosing proper exam gloves, dental hygienists should consider their preference for latex or nonlatex, skin sensitivity, size, fit, and tactile sensitivity. Utility gloves are typically underutilized; however, they should be routinely worn when processing dental instruments, cleaning and disinfecting treatment rooms, and any time chemicals are used.²¹

Donning and Doffing Protocol

Appropriate PPE donning and doffing are critical, and proper technique is critical to ensuring safety. The CDC provides step-by-step directions regarding proper PPE donning and doffing procedures.²² The fast pace of a dental office environment and human error can often make it difficult to comply with these guidelines.

According to a study by Phan et al,²³ 90% of healthcare workers’ doffing practices did not follow the CDC guidelines in terms of proper use of PPE, doffing technique, or doffing sequence. Improper doffing may cause the transfer of pathogens to the dental professional’s skin or clothing, leading to self-contamination.²⁴ This reiterates the significance of proper donning and doffing of PPE to ensure optimal protection and safety.

When doffing PPE, the most contaminated item is always removed first, before the least contaminated item. According to the CDC guidelines, examination gloves should be removed first, followed by the face shield/​eyewear, and then the protective gown or lab coat. The last step is to carefully remove the mask/​respirator. Following removal of all contaminated PPE, the dental professional must always finish with proper handwashing or hand sanitizing.²²

Conclusion

The importance of proper PPE use cannot be overstated. All oral health professionals must stay abreast of the most recent infection control guidelines to protect themselves, their co-workers, and their patients. Evidence-based directives should be followed when deciding on PPE and proper donning and doffing procedures must be followed to avoid cross- (or self-) contamination. Regulatory agencies, such as the CDC, OSHA, and OSAP, as well as individual state laws offer current guidance and resources. These include recommendations and best practices for the most current infection control guidelines and PPE usage.

References

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3. Dudding T, Sheikh S, Gregson F, et al. A clinical observational analysis of aerosol emissions from dental procedures. PLoS One. 2022;17:e0265076.
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18. Kraus CK. Mask effectiveness against viral illnesses in health care professionals. J Am Coll Emerg Physicians Open. 2021;2:e12583.
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20. Moore J. Safe and effective use of gloves. Dimensions of Dental Hygiene. 2018;16(12): 23–25.
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22. United States Centers for Disease Control and Prevention. PPE sequence. Available at: cdc.gov/​hai/​pdfs/​ppe/​ppeposter148.pdf. Accesed October 24, 2023.
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From Dimensions in Dental Hygiene. November/December 2023; 21(10):10,13-14.