Infection Control and Prevention in Dental Practices

Posted on Dec 3, 2024 in Biology

Infection Control in Dental Practices

Contamination and Infection

The mouth cavity can be contaminated by various germs. Infection occurs when the body is invaded by an external agent capable of causing disease.

Routes of Transmission

• Direct Contact: Occurs through contact with organic fluids (blood, saliva) that directly penetrate the body via oronasopharyngeal routes, skin wounds, conjunctiva, or other mucous membranes.
• Indirect Contact (Fomites): Occurs through contact with contaminated instruments (scalpels, needles) that penetrate the skin or mucous membranes.

Commonly Transmitted Microorganisms

The following pathogens are frequently transmitted in dental settings:

Antisepsis and Infection Control

Antisepsis is the chemical disinfection of the skin, mucosa, or other objects using antiseptic substances. The American Dental Association (ADA) recommends treating all patients as potential sources of infection and implementing universal precautions.

Personal Hygiene Measures

• Cover cuts and wounds with dressings.
• Keep nails short and unpainted.
• Tie hair back.
• Change uniforms daily, including clothing and footwear.
• Wash hands before and after treating each patient.

Barrier Protection Techniques

Barrier techniques aim to create a physical space to protect individuals from contamination. These include:

• Gloves: The most crucial barrier, to be changed between patients and if torn. Types include latex, vinyl, and nitrile.
• Masks: Protect the professional and patient from nasopharyngeal infections. Change after each patient or if it becomes wet.
• Safety Goggles: Protect eyes from splashes or aerosols. Wash and disinfect after each use.
• Face Shields: Provide additional protection during procedures that generate splashes or aerosols. Wash and disinfect after each use.
• Gowns and Uniforms: Should be long-sleeved and close-fitting to minimize germ harboring.
• Hair Covers: Especially important during surgical procedures.
• Rubber Dam: Isolates the treatment area and reduces aerosols.
• Protective Dental Chair Covers: Cover various chair parts, including headrest, seat, and handles.
• Immunization: Recommended vaccinations for dental professionals include Hepatitis B, Tetanus, and Influenza.

Sharps Handling

• Point sharp tips away from the body.
• Dispose of used needles and scalpel blades immediately in designated sharps containers.
• Wear heavy-duty gloves when handling sharps.
• Do not recap needles.
• Use appropriate disposal containers for non-recyclable sharps.

Instrument and Equipment Hygiene

Proper instrument hygiene is crucial to prevent infection transmission. The process includes:

• Soaking and Disinfection: Instruments are immediately immersed in a disinfectant solution to soften organic debris and reduce pathogens.
• Cleaning: Can be done manually, mechanically, or ultrasonically.
• Drying and Lubrication: Prevents corrosion.
• Packaging: Use self-sealing bags or metal cases to maintain sterility.
• Sterilization: Destroys all microorganisms, including spores. Methods include steam sterilization (autoclave) and chemical sterilization (glutaraldehyde).

Disinfectants

• High-Level Disinfectants: Inactivate all microorganisms, including spores (e.g., glutaraldehyde).
• Low-Level Disinfectants: Inactivate vegetative bacteria and fungi (e.g., sodium hypochlorite, phenols).

Material Classification and Sterilization Methods

Sterilization Monitoring

• Chemical Indicators: Change color to indicate sterilization temperature has been reached.
• Biological Indicators: Use bacterial spores to verify sterilization effectiveness.

Waste Management

Proper waste disposal is essential. Use designated containers for:

• Sharps waste
• Contaminated disposable materials
• Extracted teeth (sterilize before returning to patient)
• Amalgam waste
• Liquid waste (developer and fixer)

Fluoride Application

Fluoride strengthens teeth and makes them more resistant to decay. It can be applied systemically or topically.

Systemic Fluoride

• Fluoridated Water
• Fluoride Supplements (tablets, drops, chewing gum)
• Fluoridated Salt

Topical Fluoride

• Fluoride Solutions (2% Sodium Fluoride)
• Fluoride Gel
• Fluoride Varnish (for children under 6 and patients with disabilities)
• Toothpastes and Mouth Rinses

Note: A lethal dose of fluoride is 5 grams, causing abdominal pain, vomiting, diarrhea, and arrhythmias.