I CAN recall a few occasions in which patients visiting my clinic ask about the likelihood of their contracting an infection. I spent a couple of weeks in New York before returning home a few days ago, and my research confirms that this is not too rare. In the so-called developed countries, on several occasions, persons have expressed concern about the possibility of patients acquiring AIDS from their dentist. The universal public interest in this matter has resulted in an investigative study, which was recently conducted in the United States.

Worldwide apprehension began back in July 27, 1990 when the Center for Disease Control and Prevention reported the possible transmission of HIV from a Florida dentist to a patient during extraction of two upper third molars. The dentist had been diagnosed with AIDS three months before the invasive dental procedure.

On June 14, 1991, the CDC published findings suggesting that HIV transmitted to as many as five of the nearly 850 patients evaluated in this case. They concluded by stating that it was the only investigation in which transmission of HIV from an infected health care worker to patients during invasive procedures has been strongly suggested. Neither the precise mode of HIV transmission to these patients, nor the reasons for spreading to multiple patients in a single practice are known.

Last year, the American military authorities discovered three HIV-positive dentists in the Navy. After assigning them immediately to non-clinical duties, an investigation was launched on their patients. Of the 2887 patients treated by the dentists, 71 per cent had HIV test results recorded after treatment. Of these 2039 patients, three tested HIV-positive for the first time after the dental treatment in question. Of these three, two admitted risk-relevant sexual behaviour. The presence of this high-risk behaviour suggests that these two were, most likely, not infected with HIV during dental treatment.

No HIV risk factor information was available from Navy records for the third HIV-positive patient. He is now separated from the Navy. His treatment consisted only of a dental examination, and he tested positive six days after the treatment. A dental examination is typically a non-passive procedure, and carries a low risk for HIV transmission. Also, the earliest development of HIV antibody occurs about one month after exposure to HIV. Therefore, it is unlikely that a positive antibody test only six

days after dental treatment was caused by an exposure to HIV during that treatment.

The Dental Information Retrieval System and mandatory HIV antibody testing of all active duty Navy personnel allowed the investigation to be conducted in a cost-effective manner, without patient involvement or additional testing. A limitation of this investigation is that patients were considered HIV-negative if they had never tested positive and had a negative antibody test subsequent to treatment by the HIV-positive dentist. Seroconversion (blood manifestation) is most likely within one to three months after exposure to HIV. Patients could, however, be exposed to HIV and still have a negative antibody test for up to one year after exposure.

This type of investigation cannot rule out the possibility of HIV transmission from dentist to patient during dental treatment. The instance cited herein indicates four infected dentists from a total of over fifty thousand. Guyana has thirty-six dentists, so, while the possibility will always exist for an HIV-positive dentist to infect a patient, that possibility is extremely remote.

On November 26, 2006, the Ministry of Health organized a course for dentists who deal with HIV-positive patients. I participated in that course, in which resource personnel came from the University of Alabama, USA, the University of the West Indies and the University of Guyana.  

A major conclusion arrived at was that all international study indicate that patients need not avoid dental treatment for fear of being exposed to HIV.