Viruses are ubiquitous in the environment, but fortunately only a few poseerious threat to the patient and the surgical team. The viral organisms that- cause the most difficulty are. the hepatitis Band C viruses, and the
human immunodeficiencv virus (HIVi. These viruses have differences in their’ susceptibility to nation that are important to understand when attempting to
prevent their spread. Each virus is described here with respect to hardiness and usual mode of transmission. In addition, the circumstances in which the clinician might suspect that an individual is carrying one of these viruses
is briefly described, allowing the surgical team. to take necessary precautions.
Hcpatitis viruses. Hepatitis A, B, C, and D viruses are responsible for most infectious hepatic diseases. Hepatitis A is spread primarily by contact with the feces of infected individuals. Hepatitis C may spread either through
contaminated feces or by contaminated blood. Hepatitis’ Band D are spread by contact with any human secretion.
The hepatitis B virus has the most serious risk of transmission for unvaccinated dentists, their staffs, and their patients. It is usually transmitted by the introduction of infected blood into the bloodstream of a susceptible person; however, infected individuals may also crete large
amounts of the virus in their saliva, which can enter an individual through any moist mucosal surface or eplthe 1 or mucoval) wound. xtmute quantities of the ,ru have been found capable of transmitting disease
only 10″ to 10′ virions/nil, of 9100d). Unlike most virus the hepatitis virus is exceptionally resistant to desiecatlon and chemical dlslnfeftants, including alcohols, phenols, and quaternary ammonium compounds. There- in the hepatitis B virus is difficult to contain, particularly
when oral surgery is being performed.
Fortunately, means of inactivating the virus include halogen-containing disinfectants (e.g., iodophor, hypohlorite), formaldehyde, ethylene oxide gas, all types of properly performed heat sterilization, and irradiation.
These methods can be used to minimize the spread of hepatitis from one patient to another.
In addition to preventing patient-to-patient spread, the dentist and staff also need to take precautions to protect themselves from contamination, because several instances haw occurred in which dentists have been the
prlmary source of a hepatitis B epidemic. Dentists who perform oral surgical procedures are exposed to blood and saliva; therefore the dental surgery team should wear barriers to protect against contaminating any open wounds on the hands and any exposed mucosal surfaces.
This includes wearing gloves, a face mask, and eyeglasses or goggles during surgery. The dental staff should continue to wear these protective devices when cleaning instruments and when handling impressions, casts, ‘or specimens from jJiltients. A common means of hepatitis inoculation is injury with a needle or blade that is contaminated with blood or saliva. In addition, members of the dental staff should receive hepatitis B vaccinations, which have been shown to reduce an individual’s susceptibility to hepatitis B infection effectively, although the
longevity of protection has not been definitively determined (Fig. 5-11. Finally. office-cleaning personnel and cornmerclal Taborator , technicians can be protected by
proper segregation and Jabeling of contaminated obit?
and by proper disposal of sharp objects (Box 5-1)
Recognition of all individuals known to be carries of hepatitis Band C would aid in knowing when special precautions were necessary. However, only about half of th people infected with hepatitis ever have clinical signs and
symptoms of the infection, “and some individuals who have completely recovered from the disease still shed intact virus particles in their secretions.
The concept of universal precautions was developed 0f address the inability of health care providers to specically identify all patients with communicable disease The theory on which the universal precautions COIKer j based is that protection of self, staff, and patients from
contamination by using barrier techniques when trcatinc all patients as if they all had a communicable disea e ensures that everyone is protected from those who do have an infectious process.
Universal precautions typically ‘include having all doctors and staff who come in contact with patient blood or secretions, whether directly or in aerosol form, wear barrier devices, including a face mask, eye protection, and .gloves. Universal precaution procedures go on to include decontaminating or disposing of all surfaces that are exposed to patient blood, tissue, and secretions. Finally, universal precautions mandate avoidance of touching, and thereby contaminating, surfaces (e.g., the dental record, telephone) with contaminated gloves or instruments.
Methods Designed.to Limit the Spread of Hepatitis Viruses