Selection and Use of Personal Protective Equipment (PPE)

Types of Gloves

Gloves vary in material, fit, and purpose:

• Nitrile: A synthetic rubber that is highly puncture-resistant.
• Latex: Offers good sensation but carries risks of hypersensitivity.
• Vinyl: A cheaper option, though it often has a looser fit.
• Polyurethane: An alternative non-latex material.

Gloves are further categorized by their sterility and use case. Exam gloves are typically non-sterile and used for general contact, while sterile surgical gloves are used for invasive procedures. In dental settings, "over-gloves" may be used over contaminated gloves to touch non-contaminated surfaces, or nitrile utility gloves may be used when decontaminating the operatory or handling sharps.

Latex Hypersensitivity and Dermatitis

The use of latex can lead to skin issues, classified as either Contact Dermatitis (irritant or allergic) or Latex Hypersensitivity. There are two main types of allergic reactions to latex:

1. Type I (Immediate): Characterized by itching and redness (erythema) of the hands, which can escalate into systemic reactions such as bronchospasm, hypotension, or even fatal anaphylaxis.
2. Type II (Delayed): Occurs approximately 2 to 3 days after exposure, presenting as itchy, dry, or broken skin.

To mitigate these risks, clinics should use powder-free, non-latex alternatives like nitrile or vinyl. Furthermore, because latent allergens can become airborne, patients with known latex allergies should be scheduled for the first appointment of the day to minimize exposure to airborne particles.

Respiratory and Facial Protection

Masks and Respirators

Masks protect the nose and mouth and should be designed to prevent fluid penetration. A high-quality surgical mask may consist of three layers: an outer esthetic layer, a middle fluid shield, and an inner soft layer compatible with skin. Clinicians must be aware of "strike-through," which occurs when liquids pass from the outer layer to the inner surface; using impervious, fluid-resistant masks helps prevent this.

If a mask does not fit tightly, "blow-by" can occur, where air enters through the periphery, bypassing the filtration. For higher levels of protection, NIOSH-rated respirators are used. The rating is based on the ability to capture the most penetrating particle size (0.3µm):

• N95: Captures at least 95% of particles.
• N99: Captures 99% of particles.
• N100: Captures 99.97% of particles.

Eye and Face Protection

Protective eyewear can include goggles, polycarbonate glasses with side-shields, or face shields. Personal prescription glasses are not a substitute for protective goggles. Face shields provide broader protection, covering the forehead, chin, and wrapping around the sides of the face.

Donning and Doffing Procedures

The sequence in which PPE is put on (donning) and taken off (doffing) is critical to prevent self-contamination.

Donning (Putting on)

The general sequence is:

1. Gown
2. Mask or Respirator
3. Goggles or Face Shield
4. Gloves (Donned last, extending over the gown cuffs)

Doffing (Removing)

When removing PPE, the goal is to work from "clean to dirty" and avoid touching your face. The sequence for removal is often the reverse of donning to ensure the most contaminated items are handled carefully:

1. Gloves
2. Face shield or goggles
3. Gown
4. Mask or respirator

Safety Note: Always perform hand hygiene immediately after removing PPE.

Summary of Best Practices

To maintain a safe environment, clinicians should:

• Limit Contamination: Avoid touching the face or adjusting PPE with contaminated gloves.
• Change Frequently: Change gloves if they tear, become heavily soiled, or after treating each patient.
• Proper Disposal: Discard all single-use PPE in appropriate receptacles; never wash or reuse disposable gloves.
• Hand Hygiene: Wash hands with antimicrobial soap before donning gloves to reduce resident bacteria on the skin.