Infection control is a rapidly expanding and changing area within modern dentistry. New diseases continue to emerge and familiar pathogens have become resistant to antibiotics and antiseptics. Today more than at any time in history patients, dentists and medical staff are concerned about the risk of disease transmission in a dental clinic. All members of dental team play a very important role in organizing, managing and implementing the infection control program in a dental clinic.
There are several factors affecting infection transmission: source of infection, means of infection, route of transmission, susceptible host. Routes of infection in dentistry include direct contact with contaminated material (unprotected hands, droplets, spatter on mucosa of eyes, mouth, nose), indirect contact (touching contaminated instruments), aerosol (tribune burs, ultrasound tips), parenteral (sharp injuries: needle stick injury, scalpel cut).
Infectious diseases presenting concern in dental practice are: viral infection, bacterial infection, fungal infection, parasitic infection (table 6.1, 6.2).
Table 6.1. Bacterial infection
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Mycobacterium tuberculosis | |
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Table 6.2. Viruses
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| Transmission occurs by direct contact with abraded skin or intact mucosa with infected lesion or secretion |
| Direct contact between infected host and mucosal surface of skin wound. Small amount of virus present in saliva. According to common data a person cannot be infected with saliva alone |
Infective dose is a number of organisms required to cause an infection; it depends on virulence of infectious agent, susceptibility of host, etc. Way of contamination can be of the following types.
1. Bloodborne: bleeding/surgical procedure: hepatitis B, hepatitis C, HIV.
2. Airborne:
a) small droplets containing infectious agents emitted by infected person who coughs, sneezes, talks: influenza virus;
b) large droplets (splash, splatter) generated by specific procedure involve close contact: they contaminate hands of dental staff, objects, instruments, and are further transferable to eyes, mouth, other objects, other patients.