Direct transmission occurs when someone comes into direct contact with the infectious lesion or infected body fluids (e.g., blood, saliva, semen, vaginal secretions).
Indirect transmission involves the transfer of organisms to a susceptible person through, for example, the handling of contaminated instruments or touching of contaminated surfaces and then touching the face, eyes, or mouth.
Splash or spatter transmission happens during a dental procedure when the mucosa (mouth or eyes) or nonintact skin is splashed with blood or blood-contaminated saliva.
Parenteral transmission can take place through needlestick injuries, human bites, cuts, abrasions, or any break in the skin.
Bloodborne transmission involves direct or indirect contact with blood and other body fluids.
Food-and-water transmission occurs when contaminated food that has not been cooked or refrigerated properly or water that has been contaminated with human or animal fecal material is consumed.
Fecal/oral transmission occurs when proper sanitation procedures, such as handwashing after use of the toilet, are not followed and one of the many pathogens present in fecal matter is transmitted when the infected person touches another person or makes contact with surfaces or food.
Roles and Responsibilities of CDC and OSHA in Infection Control
The Centers for Disease Control and Prevention (CDC) and the Occupational Safety and Health Administration (OSHA) are federal agencies that play very important roles in infection control for dentistry.
The CDC is not a regulatory agency. Its role is to issue specific recommendations based on sound scientific evidence on health-related matters.
CDC’s recommendations are not law, but they do establish a standard of care for the dental profession.
OSHA is a regulatory agency. Its role is to issue specific standards to protect the health of employees in the U.S.
In 1991, based on the CDC guidelines, OSHA issued the Bloodborne Pathogens Standard (BBP).
CDC Guidelines for Infection Control in Dental Health-Care Settings
In December of 2003, the CDC released the Guidelines for Infection Control in Dental Health Care Settings-2003.
The new guidelines have expanded upon the existing OSHA Bloodborne Pathogens Standard, and have included some areas that were not already covered.
The guidelines are based on scientific evidence and are categorized on the basis of existing scientific data, theoretical rationale, and applicability.
The guidelines apply to all paid or unpaid dental health professionals who might be occupationally exposed to blood and body fluids by direct contact or through contact with contaminated environmental surfaces, water, or air.
The bloodborne pathogens standard (BBP) is the most important infection control law in dentistry.
It is designed to protect employees against occupational exposure to bloodborne pathogens, such as hepatitis B, hepatitis C, and human immunodeficiency virus (HIV).
Employers are required to protect their employees from exposure to blood and other potentially infectious materials (OPIM) in the workplace and to provide proper care to the employee if an exposure should occur.
Exposure control plan clearly describes how the office complies with the standard.
The term Universal Precautions is referred to in the OSHA Bloodborne Pathogens Standard.
Universal precautions is based on the concept that all human blood and body fluids (including saliva) are to be treated as if known to be infected with the bloodborne disease, HBV, HCV, or HIV.
The CDC expanded the concept and changed the term to Standard Precautions.
Standard Precautions integrate and expand the elements of universal precautions into a standard of care designed to protect healthcare providers from pathogens that can be spread by blood or any other body fluid, excretion, or secretion.
It is not possible to identify those individuals who are infectious, so infection precautions are used for all healthcare personnel and their patients.
Keep nails short and well manicured; rings (except for wedding rings), fingernail polish, and artificial nails are not to be worn at work.
Microorganisms thrive around rough cuticles and can enter the body through any break in the skin.
Dental personnel with open sores or weeping dermatitis must avoid activities involving direct patient contact and handling contaminated instruments or equipment until the condition on the hands is healed.
Protective clothing should be made of fluid-resistant material.
As a means of minimizing the amount of uncovered skin, clothing should have long sleeves and a high neckline. Note: The type and characteristics of protective clothing depend on the anticipated degree of exposure.
The design of the sleeve should allow the cuff to be tucked inside the band of the glove.
During high-risk procedures, protective clothing must cover dental personnel at least to the knees when seated.
Buttons, trim, zippers, and other ornamentation should be kept to a minimum.
Because dental personnel are most likely to come into contact blood or contaminated items with their hands, gloves may be the most critical PPE.
You must wear a new pair of gloves for each patient, remove them promptly after use, and wash your hands immediately to avoid the transfer of microorganisms to other patients or the environment (CDC guideline).
Consult with the glove manufacturer regarding the chemical compatibility of the glove material and the dental materials you use (CDC guideline).
When a latex allergy has been diagnosed in one employee in the dental office, all staff members should use practices to minimize the use of latex-containing products. These practices include the wearing of powder-free gloves by all dental staff members to minimize the risk of airborne latex particles.
Medical waste is any solid waste generated in the diagnosis, treatment, or immunization of human beings or animals in research.
Infectious waste is a subset of medical waste. Only a small percentage of medical waste is infectious and needs to be regulated.
Containers of infectious waste (regulated waste) must be labeled with the universal biohazard symbol, identified in compliance with local regulations, or both.
Containers used for holding contaminated items must be labeled. Examples of such containers include contaminated sharps containers, pans or trays used to hold contaminated instruments, bags of contaminated laundry, specimen containers, and storage containers.
Never eat, drink, smoke, apply cosmetics or lip balm, or handle contact lenses in any area of the dental office where contamination is possible, such as the dental treatment rooms, dental laboratory, sterilization area, or the area for the processing of x-rays.
Never store food or drink in a refrigerator that contains any potentially contaminated items.
You can minimize the amount of splash and spatter contamination produced during dental procedures with the skillful use of a dental dam and high-volume evacuation.
CDC Guidelines Special Considerations: Saliva Ejectors
Do not advise patients to close their lips tightly around the tip of the saliva ejector to evacuate oral fluids.
Rationale: Backflow from low-volume saliva ejectors occurs when the pressure in the patient’s mouth is less than that in the evacuator. This backflow can be a source of cross-contamination between patients. Although no adverse health effects associated with the saliva ejector have been reported, you should be aware that in certain situations backflow could occur with the use of a saliva ejector.
CDC Guidelines Special Considerations: Dental Laboratories
Use PPE when handling items in the laboratory until they have been decontaminated.
Clean, disinfect, and rinse all dental prostheses and prosthodontic materials (e.g., impressions, bite registrations, occlusal rims, and extracted teeth).
Consult with manufacturers regarding the stability of specific materials (e.g., impression materials) relative to disinfection procedures.
Clean and heat-sterilize heat-tolerant items used in the mouth (e.g., metal impression trays and face-bow forks).
Follow manufacturers' instructions for cleaning, sterilizing, or disinfecting items that become contaminated but do not normally come into contact with the patient (e.g., burs, polishing points, rag wheels, articulators, case pans, and lathes.) If manufacturer instructions are unavailable, clean and sterilize heat-stable items and disinfect them.
CDC Guidelines Special Considerations: Creutzfeldt-Jakob Disease and Other Prion Diseases
Creutzfeldt-Jakob Disease (CJD) belongs to a group of rapidly progressive and invariably fatal degenerative neurologic disorders.
They affect both human beings and animals and are thought to be caused by infection with prions.
Prion diseases have an incubation period of years but are usually fatal within 1 year of diagnosis.
The infectivity of oral tissues in CJD patients is an unresolved issue. Scientific data indicate that the risk, if any, of sporadic CJD transmission during dental and oral surgical procedures is low to nil.
No recommendation is offered regarding the use of special precautions in addition to standard precautions in the treatment of patients with known CJD (unresolved issue).
CDC Guidelines Special Considerations: Laser/Electrosurgery Plumes or Surgical Smoke
In surgical procedures involving the use of a laser or electrosurgical unit, a smoke byproduct is created during the thermal destruction of the tissue.
Laser plumes and surgical smoke pose a risk to dental healthcare professionals.
One concern is that the aerosolized infectious material in the laser plume may reach the nasal mucosa of the operator or other members of the dental team. However, airborne exposure to an infectious agent in a laser plume might not be enough to cause disease.
The effect of the exposure (e.g., disease transmission or adverse respiratory effects) on dental healthcare professionals resulting from the use of lasers in dentistry has not been adequately evaluated (unresolved issue).