HIV and dental infection control

Human immunodeficiency virus (HIV) is the virus that causes AIDS. Although dental health care professionals may be exposed to various infectious diseases in the blood and saliva of patients (including HIV), the risk of contracting HIV through dental exams or procedures is considered small. The risk is not zero, however. The specific circumstances that may lead to HIV infection during dental procedures have not been determined.


General information
Federal, state and local public health departments have conducted numerous investigations of how often HIV is transmitted from HIV-infected health care providers to patients. Because HIV has different strains, scientists can trace an epidemic by comparing the gene sequences with DNA testing. This way, they can tell if two people infected with HIV were infected with the same strain, raising the likelihood that one infected the other.
In 1990, an American dentist who had HIV was thought to have infected five of his patients with the virus. Amid much media attention and controversy, the Centers for Disease Control and Prevention (CDC) concluded that at least three of the patients had been infected during their dental care, but the specific route of HIV transmission was unknown. Studies have been reassuring in that there have been no additional cases of HIV passed from health care providers to patients in the United States.


Prevention
The CDC and the American Dental Association have established a set of procedures for dental staff involved in direct patient care to help prevent transmission of the virus, both from patient to provider and provider to patient. These safety steps, which are described below, are called universal precautions. The CDC does not recommend health care workers infected with HIV be barred from performing invasive procedures, but instead refers these situations to individual case review.
Hygiene
Dental professionals must wash their hands before each patient visit. For nonsurgical procedures, plain soap and water is satisfactory. For surgical procedures, an antimicrobial soap is recommended. Dental workers must also wash their hands after touching objects likely to be contaminated and before leaving the patient room.

Dental professionals who have hand injuries or draining or weeping dermatitis (inflammation of the upper layers of skin) should not participate in direct patient care.

Gloves
Latex or vinyl gloves must be worn when the dental worker's skin is likely to contact saliva, blood or mucous membranes of the mouth. Gloves should also be changed routinely between each patient and should be worn for simple exams as well as dental procedures. If the gloves are torn, punctured or cut, the dental professional should wash his or her hands and put on a new pair of gloves as soon as patient safety allows.

Protective clothing
Gowns, lab coats, aprons or other types of outer clothing must be worn when exposure to body fluids is probable. This outer layer of clothing should be changed daily or sooner if it becomes stained with body fluids. It should never be mixed with nonmedical laundry and must be washed on the premises or by a laundry facility with expertise in medical laundry procedures.

Masks and eyewear
Face shields or surgical masks and protective eyewear must be worn when spattering of body fluids may occur. Face shields and eyewear should be cleaned as needed. Masks should be changed when they become wet or soiled.

Office equipment covering
Surfaces that are difficult to clean, such as light handles or parts of X-ray units, should be covered with paper, foil or plastic wrap. The protective covering should be changed after each patient visit.

Disposal of waste material
Disposable syringes, needles, scalpel blades and other sharp objects must be disposed of in a specifically designated biohazard puncture-resistant container. Disposable items such as gloves, masks, gowns and gauze that are contaminated with body fluids must be discarded in a leakproof plastic bag. Requirements for disposal of these containers are outlined by state or local environmental regulatory agencies.

Disinfection and sterilization
Disinfection eliminates microorganisms that cause disease or infection. Sterilization completely rids an object of all living organisms. Sterilization may be done through steam under pressure (also called autoclave), dry heat or chemical vapor.

All instruments that penetrate tissue or bone must be sterilized after each use. Equipment and instruments that come in contact with body fluids should also be sterilized after each use. When this is not possible, high-level disinfection should be done. Water lines attached to hand instruments that come in contact with mucous membranes must be flushed between patients and at the beginning and end of each day. Floors, sinks and counters may be cleaned with standard disinfectants. Infections are unlikely to be contracted through exposure to these surfaces.

Contamination
While providing patient care, dental professionals should limit contact with charts, telephones and cabinets.

Patient responsibility
Each patient should have a complete medical history on file at the dentist's office. The histories should be routinely updated. When you visit a dental office, the American Dental Association suggests considering the following factors:

The dental office should be clean and neat.
The dental staff should be helpful and willing to answer your questions.
The dentist and other staff members should wear gloves and other appropriate protective gear during all types of patient treatment.
The dentist and other staff members should wash their hands before putting on gloves.
All surfaces and equipment in the treatment room should appear clean.
Needles and other sharp items should be disposed of in special puncture-resistant containers.
All objects that are used in patients' mouths should be either sterilized or disposable.
Finally, remember that universal precautions and other infection control safeguards should be standard practice in all dental offices. If you are particularly concerned about the possibility of being infected with HIV, however, share your concern with your dentist.