Oklahoma dentist to be tested for potential exposure to HIV, hepatitis B and hepatitis C.

The possible exposure happened at the dental practice of Dr. W. Scott Harrington in Tulsa, Okla., and Owasso, Okla. Officials are sending letters to 7,000 patients who have visited the facilities since 2007, according to a health department news release.

Records were available only from 2007 through March, so patients who visited Harrington's practice before then were urged to contact health officials.

Harrington, an oral surgeon who has been licensed since the 1970s, surrendered his credentials March 20 and discontinued his practice after investigators discovered alleged health and safety violations. Authorities say he is cooperating.

The health departments noted that transmissions of these diseases in this type of occupational setting are rare. Kristy Bradley, state epidemiologist, stressed that "this is not an outbreak."

The state health department said that HIV and hepatitis B "have been known to be transmitted in the dental setting" but that there is no documentation of hepatitis C infection. The tests are being recommended as a precaution.

According to the Oklahoma Board of Dentistry, the investigation so far has uncovered "numerous violations of health and safety laws and major violations of the state dental act."