7.1 Personal Protective Equipment (PPE) Selection, Donning & Doffing

Personal Protective Equipment (PPE) Selection, Donning & Doffing

Quick Answer: Personal Protective Equipment (PPE) is specialized clothing or equipment worn by dental healthcare personnel to protect against contact with infectious blood, saliva, contaminated airborne aerosols, and hazardous chemicals. Under the OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030), employers must provide, maintain, and launder all PPE at no cost to employees. The standard CDC donning sequence is: Gown → Mask/Respirator → Eyewear/Face Shield → Gloves. The standard doffing sequence is: Gloves → Eyewear/Face Shield → Gown → Mask/Respirator → Immediate Hand Hygiene. Single-use examination gloves must never be washed or disinfected, and heavy-duty utility gloves are mandatory for operatory disinfection and instrument processing.

In oral healthcare, personal protective equipment acts as a primary physical barrier interrupting the Chain of Infection between the patient's oral cavity and the clinician. Because dental procedures routinely generate high-velocity spatter, microbial aerosols, and sharp instrument hazards, dental assistants must master the exact criteria for PPE selection, maintenance, donning, and doffing.

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1. Regulatory Framework: OSHA Mandates & Employer Responsibilities

The Occupational Safety and Health Administration (OSHA) enforces legal standards to protect healthcare workers from workplace hazards, while the Centers for Disease Control and Prevention (CDC) issues evidence-based infection prevention guidelines.

                      OSHA PPE REGULATORY MANDATES
   +-------------------------------------------------------------------------+
   | 1. EMPLOYER PROVISION  | Must provide appropriate PPE in correct sizes  |
   |                        | at NO financial cost to the employee.          |
   | 2. OFFICE LAUNDERING   | Protective clothing MUST be laundered in-office|
   |                        | or by a commercial service; NEVER taken home.  |
   | 3. REMOVAL MANDATE     | All PPE must be removed prior to exiting the   |
   |                        | clinical treatment area or entering staff areas|
   | 4. MAINTENANCE/REPLACE | Employer must clean, repair, or replace torn   |
   |                        | or compromised PPE at no expense to worker.    |
   +-------------------------------------------------------------------------+

Hierarchy of Hazard Controls

Under OSHA's industrial hygiene hierarchy, PPE is the final line of defense against occupational hazards:

1. Elimination / Substitution: Physically remove or replace the hazard (rarely possible in clinical dentistry).
2. Engineering Controls: Isolate people from the hazard (e.g., sharps disposal containers, rubber dams, High-Volume Evacuation [HVE], safety scalpels, self-sheathing anesthetic needles).
3. Work Practice Controls: Alter the manner in which a task is performed to reduce exposure risk (e.g., one-handed scoop technique for needle recapping, prohibiting two-handed needle recapping, instrument cassettes).
4. Personal Protective Equipment (PPE): Protect the worker with personal gear (gowns, masks, eye protection, gloves).

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2. Protective Clothing & Clinical Gowns

Protective clothing shields intact skin, non-intact skin, and street clothing from contact with blood, saliva, and infectious fluids.

Clinical Specifications

• Coverage: Must feature a high neck (mandarin collar), long sleeves with ribbed knitted cuffs that tuck securely under exam gloves, and full coverage of the torso and lap down to the knees when seated chairside.
• Material: Made from fluid-resistant synthetic fabric or heavy reusable cotton-polyester blends designed to prevent strike-through of liquids.
• Fasteners: Fastened at the neck and waist with snaps, buttons, or ties to prevent gaping.

                       PROTECTIVE GOWN SPECIFICATIONS

                [ High Mandarin Collar ]  <-- Protects Neck / Clavicle
                      /         \
           [ Long Sleeves ]   [ Long Sleeves ]
                 |                  |
           [ Knit Cuffs ]     [ Knit Cuffs ]  <-- Tucked UNDER Gloves
                 \                  /
                  [ Knee-Length Lap ]         <-- Covers Lap When Seated

Handling and Changing Guidelines

• Visibly Soiled Attire: Must be changed immediately if penetrated or visibly contaminated with blood or other potentially infectious materials (OPIM).
• Daily Replacement: Must be changed daily or between patient sessions if compromised.
• Operatory Zone Restrictions: Protective gowns and lab coats must never be worn outside the clinical operatory area (e.g., forbidden in staff breakrooms, restrooms, administrative reception desks, or outside the dental facility).
• Laundering Ban: Under 29 CFR 1910.1030, taking clinical attire home to wash is a severe OSHA violation due to the risk of contaminating personal family laundry.

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3. Respiratory Protection: Surgical Masks vs. Particulate Respirators

Dental procedures utilizing high-speed handpieces, ultrasonic scalers, and air-water syringes generate airborne spatter (>50 µm) and aerosols (<50 µm). Proper respiratory selection prevents inhalation and mucosal exposure.

ASTM International Mask Performance Standards

Surgical masks are classified into three performance levels according to ASTM F2100 standards:

Surgical Masks vs. NIOSH-Approved N95 Respirators

               SURGICAL MASK vs. NIOSH-APPROVED N95 RESPIRATOR

       SURGICAL DENTAL MASK                    NIOSH N95 RESPIRATOR
   +----------------------------+       +----------------------------+
   | • Loose-fitting perimeter  |       | • Tight, airtight face seal|
   | • Fluid-resistant outer    |       | • Filters ≥ 95% particles  |
   | • Side leakage occurs      |       |   down to 0.3 micrometers  |
   | • Protects from SPATTER    |       | • Protects from AEROSOLS   |
   | • No annual fit test needed|       | • Mandatory annual fit test|
   +----------------------------+       +----------------------------+

• Surgical Mask Mechanics: Protects mucous membranes of nose and mouth from large droplet spatter and projectile fluids. However, because it fits loosely around the cheeks and chin, ambient air bypasses the filter matrix during inhalation (perimeter leakage).
• N95 Filtering Facepiece Respirator: Forms a tight, airtight seal against the clinician's facial skin. Filters at least 95% of airborne particulate matter down to 0.3 micrometers. Required for treating patients with suspected airborne diseases (e.g., active tuberculosis in emergency settings) or during intense aerosol procedures where full respiratory containment is indicated.
• OSHA Respiratory Protection Standard (29 CFR 1910.134): Requires an initial medical evaluation, annual professional fit-testing, training, and a mandatory user seal check (positive/negative pressure test) every time an N95 respirator is donned.

Mask Handling Rules

1. Change Between Patients: A new mask must be donned for every patient.
2. Change When Moist: Moisture from exhaled breath compromises the electrostatic charge of the filter medium, creating a "wicking effect" that draws microbes through the fabric. If a mask becomes moist or wet (typically within 20–30 minutes in heavy aerosol environments), it must be replaced immediately.
3. Never Touch the Mask Body: Touch only the ear loops or ties during adjustment and removal.
4. Prohibition of Neck/Chin Resting: Never pull a mask down to rest beneath the chin or around the neck between procedures. This contaminates the inner lining with skin flora and operatory spatter.

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4. Eye & Face Protection (ANSI Z87.1 Standards)

Dental procedures present severe ocular hazards, including high-speed projectile tooth fragments, hardened calculus chips, chemical splashes (acid etch, sodium hypochlorite), and microbial spatter containing Hepatitis B, HIV, or Herpes simplex.

                    CLINICAL EYEWEAR REQUIREMENTS
   +-------------------------------------------------------------------------+
   | • ANSI Z87.1 CERTIFIED    | Must meet impact resistance standards.      |
   | • SOLID SIDE SHIELDS      | Top and side protection is mandatory.       |
   | • REGULAR EYEGLASSES      | NOT compliant unless fitted with ANSI-rated |
   |                           | side shields or covered by a face shield.   |
   | • FACE SHIELDS            | Must extend from forehead to below chin and |
   |                           | wrap around ears; ALWAYS worn with a mask.  |
   | • PATIENT EYEWEAR         | Mandatory for all patients during all care. |
   +-------------------------------------------------------------------------+

Clinician Eye Protection

• Must comply with the American National Standards Institute (ANSI Z87.1) standard for occupational eye and face protection.
• Eyewear must feature solid side shields (not perforated or mesh) and top brow protection to block peripheral spatter.
• Prescription Glasses: Everyday corrective glasses lack impact-rated lenses and side shielding. Clinicians must wear ANSI-certified prescription safety glasses, clip-on side shields, or a full-face shield over their glasses.
• Face Shields: Full-face shields provide expansive facial coverage from forehead to below the chin. A face shield does not replace a mask; it must always be worn in combination with a surgical mask or respirator.

Patient Eye Protection

• Patients must be provided with tinted or clear protective eyewear during all clinical procedures.
• Protects patient eyes from dropped sharp instruments, bur slippage, spattering saliva/blood, high-intensity curing lights, and caustic chemicals (e.g., 37% phosphoric acid etching gel).

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5. Glove Selection, Types & Dermatological Considerations

Gloves are the final PPE item donned before touching intraoral tissues or contaminated surfaces.

                    DENTAL GLOVE CLASSIFICATION MATRIX
   +-------------------------------------------------------------------------+
   | PATIENT EXAMINATION GLOVES | Non-sterile nitrile, latex, vinyl, or     |
   |                            | chloroprene for routine dental procedures. |
   +-------------------------------------------------------------------------+
   | STERILE SURGICAL GLOVES    | Individually wrapped, precise numeric      |
   |                            | sizing (6.0-8.5) for invasive surgery.    |
   +-------------------------------------------------------------------------+
   | HEAVY-DUTY UTILITY GLOVES  | Puncture/chemical-resistant nitrile. Must  |
   |                            | be worn for cleaning, processing & spills. |
   +-------------------------------------------------------------------------+
   | PLASTIC OVERGLOVES         | Thin "food-handler" gloves placed over     |
   |                            | contaminated exam gloves to touch charts.  |
   +-------------------------------------------------------------------------+

Detailed Analysis of Glove Categories

1. Patient Examination Gloves: Non-sterile, ambidextrous gloves used for routine non-surgical dental procedures (restorative, hygiene, diagnostic). Nitrile is the modern clinical standard due to high puncture resistance and allergen-free composition.
2. Sterile Surgical Gloves: Individually packaged in sterile pairs with left/right hand-specific contours and precise half-size increments. Mandated for invasive surgical procedures involving bone incision, flap reflection, or implant placement.
3. Heavy-Duty Utility Gloves: Thick, puncture-resistant, and chemical-resistant nitrile or neoprene gloves. Mandatory during:
   • Cleaning and scrubbing contaminated dental instruments
   • Loading and unloading ultrasonic cleaners and instrument washers
   • Spraying and wiping operatory surfaces with chemical disinfectants
   • Handling hazardous chemical solutions and disinfectant concentrates
   • Utility gloves may be washed, disinfected, and autoclaved according to manufacturer directions. They must be discarded immediately if they show signs of cracking, peeling, tearing, or puncture.
4. Overgloves ("Mittens" / Plastic Food-Handler Gloves): Worn over contaminated patient exam gloves to quickly retrieve an extra bur, open a supply drawer, or make a charting entry, preventing cross-contamination of clean office surfaces.

Glove Integrity & Clinical Precautions

• Single-Use Rule: Examination gloves are single-use disposable medical devices. They must be discarded after every patient or if torn during treatment. They must never be washed, disinfected, or reused because soaps and alcohol disinfectants cause microscopic pore formation ("wicking").
• Petroleum-Based Lotions: Petroleum-containing lotions can weaken latex gloves. Personnel should use only lotions that the glove manufacturer identifies as compatible with the specific latex or nonlatex product.

Types of Glove Reactions

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6. Standard Donning & Doffing Sequences

Strict adherence to the CDC sequential protocols prevents cross-contaminating clean skin and street attire.

                   DONNING SEQUENCE (Clean to Dirty)

    [ STEP 1: PROTECTIVE GOWN ]
    • Fasten securely at neck and waist; ensure torso and lap are covered.
                    |
                    v
    [ STEP 2: MASK OR RESPIRATOR ]
    • Secure ties or elastic loops; mold flexible metal nosepiece over bridge.
                    |
                    v
    [ STEP 3: EYEWEAR OR FACE SHIELD ]
    • Position safety glasses with side shields or face shield over eyes/face.
                    |
                    v
    [ STEP 4: GLOVES ]
    • Perform hand hygiene before gloving; pull glove cuffs OVER gown sleeves.

                   DOFFING SEQUENCE (Dirty to Clean)

    [ STEP 1: GLOVES ]  <-- Most heavily contaminated item removed first
    • Grasp outside of opposite glove cuff; peel off inside-out.
    • Slide un-gloved finger under remaining cuff; peel off inside-out.
                    |
                    v
    [ STEP 2: EYE PROTECTION / FACE SHIELD ]
    • Handle by clean ear pieces or headband; place in disinfection bin.
                    |
                    v
    [ STEP 3: PROTECTIVE GOWN ]
    • Unfasten ties; peel away from neck and shoulders, folding inside-out.
                    |
                    v
    [ STEP 4: MASK OR RESPIRATOR ]
    • Grasp bottom ties/loops, then top ties; discard without touching front.
                    |
                    v
    [ STEP 5: HAND HYGIENE ]
    • Wash immediately with soap and water or apply alcohol hand rub (ABHR).

[!NOTE] CDC Alternative Combined Doffing Technique: The CDC also permits removing the gloves and gown together as a single unit by peeling the gown forward off the shoulders and rolling it down the arms, turning the gloves inside out as the sleeves are pulled off, followed by eyewear removal, mask removal, and immediate hand hygiene.

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7. Clinical Practice Traps & DANB Exam Pearls

[!CAUTION] DANB Exam Trap #1: Laundering Clinical Attire at Home An exam question may ask what a dental assistant should do if their protective lab coat becomes lightly stained with saliva. Never select "take it home to wash on a sanitize cycle"! OSHA explicitly prohibits employees from laundering protective attire at home. It must be laundered on-site or sent to a contracted commercial healthcare laundry service.

[!WARNING] DANB Exam Trap #2: Glove Cuffs vs. Gown Sleeves When donning PPE, the cuffs of the examination gloves must always be pulled over (on top of) the knitted cuffs of the protective gown sleeves. Leaving bare skin exposed between the sleeve and the glove cuff is a major contamination failure.

[!NOTE] DANB Exam Trap #3: Prescription Glasses as PPE Standard everyday prescription eyewear does NOT satisfy OSHA or CDC eye protection requirements unless fitted with certified, rigid top and side shields and manufactured to ANSI Z87.1 impact resistance standards.