Infection Control in Dentistry

Infection Control in Dentistry

• Infection control in dentistry aims to reduce the risk of cross-infection in dental clinics.
• Dental professionals are exposed to various infectious microorganisms.
• Cross-infection occurs when infectious agents are transmitted from person-to-person or inanimate objects.
• The goal of infection control measures is to lower the probability of infection transmission to an acceptable level.
• A safe environment for both patients and staff is crucial.
• Infection control procedures are not absolute, but aim to reduce infection risk to an acceptable level.

Risks Associated with Cross-infection

• Risks in dentistry are not absolute but rather a matter of probability.
• Infection control methods target reduction to an acceptable level.

Risk Assessment and Management

• Risk control in dentistry uses a universal approach.
• All patients are treated as potentially infectious.

Standard Infection Control Precautions

• Standard precautions treat all body fluids and secretions as potential sources of infection (excluding sweat).
• Use personal barriers and safe practices to prevent the transmission of blood, saliva, and respiratory secretions.

Risk Assessment in Dental Practice

• Steps in risk assessment include identifying hazards, determining who might be harmed, evaluating risks and adequacy of precautions, recording findings, and regularly reviewing/revising assessments as needed.

Infections

• Microorganisms must attach to or penetrate body surfaces to establish themselves.
• Skin damage can be a weak link in defense against infection.
• The vast majority of microbes do not cause infection.

Commensal Infections

• Commensal microbes (resident microbes) are present in the skin, gut, and mouth.
• They cause infection only when the immune system is compromised.

Breaking the Chain of Infection

• A microorganism must have a way to spread from host to host for continued disease transmission.
• Dental clinics inherently hold infection risks.
• Preventing infection involves disrupting various links in the infection cycle (susceptible host, infectious agent, means of transmission, reservoir and portal of exit).

What are some measures to break the Chain of Infection?

• Vaccination.
• Drug therapy.
• Infection Control and Prevention measures.
• These all help block transmission pathways.

Routes of Transmission

• Transmission by direct or indirect contact (contaminated surface).
• Percutaneous transmission (e.g. sharps injuries).
• Airborne transmission (aerosols generated by high speed handpieces, respiratory secretions).
• Common vehicle transmission (contaminated dental waterlines, plumbing).

Routes of Infection

• Direct contact – touching a contaminated surface/body fluids.
• Indirect contact – a contaminated surface/instrument that comes into contact with a susceptible person.
• Aerosol transmission – small droplets generated from dental procedures.
• Parenteral transmission – entry of pathogens through broken skin/contaminated instruments.
• Index case (infected patient).

Direct Contact

• Common infections spread via direct contact in dentistry include Herpes simplex virus (HSV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), hepatitis B virus (HBV).
• Risk of staphylococcal infection (ex- S. aureus, MRSA) is relevant, especially during oral surgical procedures.
• Transmission is often through the hands of healthcare workers (HCWs).
• Prevention methods include handwashing and wearing gloves, disposable aprons, decontamination of instruments between patients, and cleaning and disinfecting dental chair units between patients.

Infection by Fluids

• Prevention involves disinfectants, detergents and physical barriers.

Percutaneous Transmission

• Bloodborne viruses (BBVs) like HIV and hepatitis B and C are transmitted through the skin.
• Standard precautions must be used to prevent such infections.

Hepatitis B Virus

• A sexually transmitted disease (STD).
• A member of the Hepadnaviridae DNA family.
• Causes liver inflammation (hepatitis).
• Transmission is primarily through parenteral routes (direct contact).
• Common symptoms include fatigue, fever, loss of appetite, nausea, vomiting, abdominal discomfort, and jaundice.

Hepatitis C

• Causes both acute and chronic liver infection.
• Transmission is most commonly through IV drug use.

HIV Transmission

• Transmission routes include oral and penetrative sexual intercourse, and sharing needles/syringes for drug injection.
• HIV infection risk is much lower than hepatitis B for similar exposures.
• Routine screening helps reduce transmission by identifying and managing infected individuals.

Airborne Infections

• Aerosol droplets containing secretions like saliva and respiratory fluids are produced during dental procedures.
• Infections like mycobacterium tuberculosis (MT), rhinoviruses, VZV, and EBV can transmit via aerosols.
• Prevention includes standard precautions, well-ventilated environments, high-volume suction, and wearing masks (surgical/respirator).

Tuberculosis

• A serious infection that ranks alongside HIV and AIDS as a leading cause of death worldwide.
• Dental patient to dentist transmission is rare, but dentist-to-patient transmission can occur.
• Infection control measures for tuberculosis in dental settings include assessing personal/family history of tuberculosis, offering BCG vaccination, testing patients, and wearing recommended PPE.

Influenza

• Influenza virus causes respiratory illness with headache, fever, coryza, cough, and sore throat.
• Influenza A and B are more severe forms of illness.
• Symptoms are caused by sneezing and coughing.
• Virus is transmitted by direct contact and respiratory droplets.
• Infection control measures for flu include annual vaccination of susceptible groups, antiviral prophylaxis, hand hygiene, and respiratory etiquette.

Emerging and Re-emerging Infections

• Emerging infections challenge current control and prevention measures.
• Factors that contribute to their emergence include rapid globalization, climate change, agricultural practices, antibiotic resistance, and public health status.

Occupational Health

• Dental staff are exposed to a variety of hazardous substances, including microbial pathogens.
• Infection control includes identifying major infection hazards and ensuring adherence to infection control policies.
• Specific hazards include sharps injuries, respiratory infections from aerosols, eye and skin infections, hypersensitivity reactions (latex gloves), and mercury toxicity.

Culture of Safety

• A culture of safety in dentistry involves safe working practices, compliance with infection control policies, reporting injuries, effective management, immunization, proper use of safety devices, PPEs, and postexposure prophylaxis (PEP).
• Clear communication, vigilance, recognition and reporting of errors, impact of stress/fatigue on performance, and self-monitoring of risk behaviour are all essential considerations.
• Implementing safety procedures helps prevent the transmission of pathogens and promotes the well-being of dental staff.

Immunization Requirements

• In the UK, all clinical and non-clinical dental workers and students must maintain up-to-date routine vaccinations (tetanus, diphtheria, MMR, BCG, varicella).

MMR (Measles, Mumps, Rubella)

• A combination vaccination.
• Potential distrust of MMR in the 21st century led to poor uptake.
• MMR vaccine resurgence of measles and mumps has been observed.

Rubella

• A viral infection spread by respiratory droplets.
• Symptoms may begin with a prodrome involving low-grade fever, malaise, and mild conjunctivitis.
• Characteristic rash appears on the ears, face, and neck.
• Congenital rubella syndrome is a possible outcome of infection during pregnancy.

Varicella

• A viral infection commonly known as chickenpox.
• Occurs at any age, but disease in adults is typically more severe.
• Vesicles (blisters) appear on the skin, later causing scabs, and scarring.
• Virus becomes latent in sensory ganglia and may reactivate as shingles later in life.

Syphilis

• Caused by Treponema pallidum.
• Primarily in men who have sex with men.
• Can also be transmitted through heterosexual contact.
• Crosses the placenta and can affect the fetus.
• Oral sex is a confirmed transmission route.
• Dentists must refer patients with suspected lesions/symptoms for appropriate care.
• Infectious stages include primary chancre and secondary syphilis (mucosal lesions/ulcerations).
• Transmission to dental staff is rare but possible.

Hepatitis B vaccine

• Contains inactivated hepatitis B surface antigen, prepared from yeast cells.
• Very safe and does not cause hepatitis.
• Three standard immunizations stimulate antibody production.
• Antibody response in 1-4 months.
• 10-15% of individuals respond poorly to the vaccine.
• Factors for poor response can include age, obesity, smoking, immunosuppression, or underlying acute hepatitis.

BCG Vaccine

• A vaccine against tuberculosis.
• Common form of tuberculosis is pulmonary TB.
• Symptoms include fever, fatigue, weight loss, night sweats, persistent cough lasting more than three weeks.
• Some other symptoms may include hemoptysis (coughing up blood) and enlarged lymph nodes.
• Vaccine protection may wane over 10-15 years.
• Dental workers with no history of infection requiring monitoring/ vaccination.

This quiz covers essential principles of infection control in dental clinics. It highlights the importance of reducing cross-infection risks and implementing standard precautions to ensure safety for patients and staff. Understand the procedures and methods aimed at creating a safer dental environment.