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TYPES OF DISEASE TRANSMITTED
The dental specialist must be aware of some diseases that can be transmitted in
the dental clinic. Being aware of these diseases will make sterilization and disinfection
procedures more meaningful.
a. Hepatitis. Hepatitis is a disease caused by a virus that, even in mild cases,
damages the liver. In severe cases, liver necrosis is common. Two types of
distinguishable hepatitis are Hepatitis A and Hepatitis B. Hepatitis A is usually spread
by fecal contamination of food or drink. It has an incubation period of about 30 days.
Hepatitis B is spread by injectables and instruments that have come in contact with
contaminated blood or serum. It has a much longer incubation period (perhaps several
months) than Hepatitis A. The risk of infection exists between patients and between the
patient and the dental specialist.
b. Influenza and the Common Cold. Influenza, the common flu, is spread by
an airborne droplet and consists of many different antigenic types. Therefore, it is
difficult for a vaccine to be completely effective. New antigenic types are produced by
mutation of the viruses. The common cold is caused by two or three different viruses,
each of which may have many antigenic types.
c. Tuberculosis. Tuberculosis is spread by an airborne droplet. Inactive
tuberculosis occurs when the bacteria are walled off by the fibrous tissue. A positive
antibody test merely indicates present or previous infection with the tuberculosis
bacteria. A positive test result should always be reported to the dental or medical
officer. Tuberculosis of the oral mucosa occurs if wounds or erosions become infected
by tubercle bacilli contained in the sputum. The oral lesions vary greatly in their
appearance. The tongue is the most frequent site for these lesions. Antibiotics are
effective in the treatment of certain types of tuberculosis. Tuberculosis is becoming
more common, and drug-resistant forms are appearing.
d. Syphilis. This is a venereal disease caused by a spirochete. Since the
spirochete is anaerobic, it cannot survive for long when exposed to air. It may live long
enough to effect transmission if immediate contact is made with contaminated
instruments. Clinically, contact is made by an open wound or by contaminated
instruments penetrating the oral mucosa.
e. Gonorrhea. This is a venereal disease caused by a gram-negative
diplococcus. Primary infection is by genital contact. Secondary infection is possible via
the hands or by contaminated instruments.
MD0509
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