chapter 10 pt3 darby

Hand Hygiene Methods

  • Routine Handwash:
    • Agent: Water and nonantimicrobial soap (plain soap).
    • Purpose: Remove soil and transient microorganisms.
    • Area: All surfaces of hands and fingers.
    • Duration: Minimum 15 seconds.
  • Antiseptic Handwash:
    • Agent: Water and antimicrobial soap (FDA-cleared antiseptic handwash agent).
    • Purpose: Remove or destroy transient microorganisms and reduce resident flora (persistent activity).
    • Area: All surfaces of hands and fingers.
    • Duration: Minimum 15 seconds.
  • Antiseptic Handrub:
    • Agent: Alcohol-based handrub.
    • Purpose: Remove or destroy transient microorganisms and reduce resident flora (persistent activity).
    • Area: All surfaces of hands and fingers.
    • Duration: Until hands are dry.
  • Surgical Antisepsis:
    • Agent: Water and antimicrobial soap (FDA-cleared antiseptic handwash agent) using a surgical handscrub technique, OR water and nonantimicrobial soap, followed by an alcohol-based surgical handscrub product with persistent activity.
    • Purpose: Remove or destroy transient microorganisms and reduce resident flora (persistent activity).
    • Area: Hands and forearms.
    • Duration: 2 to 6 minutes (antimicrobial soap) or follow manufacturer's instructions (alcohol-based).

Additional Notes on Hand Hygiene

  • Bar Soap: Pathogenic organisms can be found on bar soap; liquid soap with hands-free controls is preferable.
  • Transient Microorganisms: Acquired during direct contact with patients or contaminated surfaces, frequently associated with healthcare-associated infections, and more easily removed by routine hand washing.
  • Resident Flora: Microorganisms always present on the body, not easily removed by mechanical friction, and less likely to be associated with healthcare-associated infections.
  • Persistent Activity: Prolonged or extended activity that prevents or inhibits microorganism proliferation or survival after product application (previously referred to as residual activity).
  • Waterless Products: Alcohol-based hand rubs are useful when water facilities are unavailable, but should not be used in the presence of visible soil or organic material.
  • Surgical Hand Scrub: Requires removal of all jewelry, washing hands and forearms, holding hands above elbows during rinsing, and drying with sterile towels; remove arm jewelry and hand jewelry that may interfere with glove usage.

Instrument Classification and Processing

  • Critical Instruments:
    • Definition: Penetrate soft tissue or bone.
    • Process: Sterilization.
    • Examples: Surgical instruments, periodontal scalers, surgical dental burs.
  • Semicritical Instruments:
    • Definition: Contact mucous membranes or non-intact skin.
    • Process: Sterilization or high-level disinfection.
    • Examples: Dental mouth mirrors, amalgam condensers, dental handpieces, most hand instruments.
  • Noncritical Instruments:
    • Definition: Contact intact skin.
    • Process: Low- to intermediate-level disinfection.
    • Examples: X-ray head or cone, blood-pressure cuff, facebow.

Instrument Processing Details

  • Critical Instruments: Must be heat sterilized between each use or discarded if disposable. Examples include periodontal probes, explorers, scaling and root planing instruments, and ultrasonic scaling unit tips.
  • Semicritical Instruments: Should be heat sterilized between each use. High-level disinfectants are indicated if heat sterilization is not possible; however, heat-stable or disposable alternatives are preferred due to safety concerns with chemical germicides. Some items require barrier protection and disinfection with an intermediate-level disinfectant.
  • Noncritical Instruments: Clean and disinfect with an EPA-registered low- to intermediate-level disinfectant or use surface barriers.
  • Instruments should be transferred to the sterilization area in a container labeled with the universal biohazard symbol.
  • A workflow that encourages a one-directional flow of the instruments during the entire process, which includes receiving, cleaning, inspection and packaging, sterilization, and storage should be used.

Sterilization Process

The process of cleaning instruments for reuse on patients requires close attention to specific steps that must be followed in the same sequence each time the process is performed.

  • Separate Sterilization Area: A sterilization area separate from patient treatment rooms will help reduce the risk of cross-contamination in the patient-care environment.
  • Cleaning: Presoaking or prespraying may be needed for heavily soiled instruments. Enzymatic products may be useful for items heavily soiled with blood or organic material.
  • Cleaning Methods: Automated devices (ultrasonic cleaning baths and instrument washers/disinfectors) are more effective than hand scrubbing.
  • Personal Protective Equipment (PPE): Heavy-duty gloves, face protection (face shield or goggles with mask), and a gown or lab coat should be worn throughout the instrument processing procedures until removal of sterile packs from the sterilizer.
  • Inspection and Packaging: After cleaning, instruments should be inspected for residual debris and carefully cleaned, then placed in sterilization pouches or trays intended for sterilization, and wrapped with an appropriate sterilization wrap.
  • Loading Sterilizer: Instrument packs should be placed in a single layer or loosely on their sides to allow sterilizing agent penetration. Paper/plastic pouches should be placed on their sides, with paper facing plastic of the adjacent pouch.
  • Storage: Upon removal from the sterilizer, instrument packs should be stored in a dry area away from contamination and should remain packaged until needed for patient care.

Heat Methods of Sterilization

Heat-based sterilization methods are more time efficient and reliable than chemical germicides.

  • FDA Approval: DHCP must use an FDA-approved sterilization device and follow the manufacturer's instructions for cycle time, temperature, and other parameters necessary to achieving sterilization.

  • Cleaning: Thoroughly clean instruments before placing them into appropriate packaging and sterilizing them.

  • Steam Autoclave:

    • Most common method; uses steam in a pressurized chamber to sterilize heat-stable instruments and devices.
    • Requires distilled water.
    • Two methods of air evacuation: dynamic air removal and gravity displacement.
    • Dynamic Air Removal: Air is pumped out, creating a vacuum into which steam is injected. This is a more efficient way of air removal, resulting in a shorter sterilization cycle and better penetration of steam into lumen devices.
    • Gravity Displacement: Relies on gravity to evacuate air; less efficient and results in a longer sterilization process.

  • Unsaturated Chemical Vapor Sterilizer:

    • Uses chemical vapor instead of steam, reducing humidity and the risk of instrument rust and corrosion, primarily in carbon steel instruments.
    • Sterilizers should be ventilated according to the manufacturer's instructions.

  • Dry-Heat Sterilization:

    • Uses high heat (around 350° F) for a specific amount of time.
    • Likely to damage heat-sensitive items such as dental handpieces and some plastics.

Chemical Disinfectants and Sterilants

Several classes of chemical agents are available that provide high-level disinfection and sterilization under given conditions. The CDC discourages the use of these chemicals because of their toxic properties.

Sterility Assurance

To ensure effectiveness of sterilization, several levels of sterility assurance are available, and a combination approach is best.

  • Chemical Indicators:
    • Indicate the presence of necessary parameters such as heat or steam.
    • Available as arrows or color-change indicators on pouches or tape.
    • Use chemical indicators on the inside of every packet of instruments as a signal to the user that the particular packet completed a heat sterilization process.
    • Not an indication of effectiveness of the sterilization process itself.
  • Biologic Indicators (BIs):
    • Also called spore tests, are the highest level of sterility assurance.
    • Use nonpathogenic spores resistant to the sterilization process.
    • Incubation confirms destruction of spores, indicating successful sterilization.

Spores for Biologic Indicators

  • Geobacillus stearothermophilus: Standard organism for testing steam and chemical vapor sterilization.
  • Bacillus pumilus: Organism most resistant to dry heat sterilization.
  • Dual Species: For monitoring a combination of sterilization methods.

Testing and Records

  • Spore test at least weekly and with each implantable device to verify the proper functioning and operation of the sterilizer.
  • Maintain records of spore testing and the results in the dental office.

Dental Water Quality

Water is used to irrigate surgical sites, cool dental devices, and irrigate restorative sites.

  • Nonsurgical Procedures: Standards for safe drinking water quality are established by the EPA, APHA, and AWWA.
  • Heterotrophic Bacteria Limit: <500 CFU/mL (colony-forming units per milliliter) of drinking water.
  • CDC Recommendation: All dental units should use systems providing output water meeting drinking water standards (≤500 CFU/mL) for nonsurgical procedures.

Water System Types

  • Self-contained water systems (independent water reservoir) combined with chemical treatment (periodic or continuous germicide treatment) or purifying filters.
  • Systems designed for single-chair or entire-practice water lines that purify or treat incoming water.
  • Separate water reservoirs do not prevent biofilm development and must be combined with other approaches.

Chemical Products and Filters

  • Chemical treatments remove, inactivate, or prevent biofilm formation.
  • Treatment cartridges release an active ingredient that disinfects.
  • Filter devices remove solid particles from water but may or may not remove endotoxin.

Maintenance and Monitoring

  • Train DHCP in site-specific dental unit water line treatment protocols and monitor compliance.
  • Follow manufacturer-specific directions.
  • Personnel managing independent reservoir bottles must use clean gloves and follow instructions for cleaning and aseptically managing the bottles.
  • Dental unit water line treatment products and devices are regulated by the FDA or EPA.

Surgical Procedures

  • Use only sterile solutions as coolants and irrigants in a sterile delivery device.
  • Oral Surgical Procedure: Incision, excision, or reflection of tissue that exposes normally sterile areas of the oral cavity.

Limiting Spread of Infection

  • Protective surface covers or barriers.
  • Use of high-volume evacuation.
  • Cleaning and surface disinfection.
  • Limiting touching of objects and surfaces while wearing medical gloves.
  • Management of medical waste (sharps and soft wastes).

Environmental Surface Disinfection

  • Surfaces in the dental treatment room are a potential source of infectious agents.
  • Surfaces and equipment that cannot be disassembled for sterilization should be cleaned and disinfected between each patient.

Surface Categories

  • Housekeeping Surfaces: Floors, walls, sinks; cleaned with soap and water, disinfected if visibly contaminated with blood or OPIM.
  • Clinical Contact Surfaces: Surfaces contaminated from spray, droplets, or touching with gloved hands; protected with fluid-impervious barriers changed between patients. Clean and disinfect if barriers are absent.

Examples of Clinical Contact Surfaces

  • Touch areas on the dental chair and operator chair.
  • Dental unit.
  • Dental light handle(s).
  • X-ray unit touch areas.
  • Countertops.
  • Air and water syringe handle and tubing.
  • Pencils, pens.
  • Keyboards, pointing devices, monitors.
  • Mirror for patient education.
  • Dental unit suction controls and disposable-tip connection tubing.
  • Saliva ejector holder and tubing.
  • Bracket tables and bracket tray.
  • Portable equipment.

Disinfection Levels

  • Use an EPA-registered hospital disinfectant (low-level) or an EPA-registered hospital disinfectant with a tuberculocidal claim (intermediate-level).
  • Use intermediate-level disinfectant for surfaces with visible blood or OPIM.

Precautions

  • Follow the manufacturer's directions for handling, use, and storage of all disinfectant and cleaning products.
  • DHCP performing cleaning and disinfection should wear appropriate PPE.
  • Chemical- and puncture-resistant utility gloves offer more protection than latex examination gloves.

Exposure Management

  • Risk reduction strategies include safer work practices, safer devices, PPE, proper policies and procedures, awareness of personal health status, attention to standard precautions, and education.
  • Every dental facility must have a postexposure management program for occupational exposures.

Epidemics and Pandemics

  • Epidemics: Infectious disease rapidly spreads and affects more people than expected.
  • Pandemics: Epidemic spreads worldwide.
  • During pandemics/epidemics, DHCP should follow public health department guidelines.
  • Patients should be asked about symptoms and instructed to reschedule if ill.
  • DHCP should stay home when symptomatic.
  • Spread can be reduced by hand hygiene and cough etiquette.