The Colorado Department of Public Health and Environment is advising anyone who was a patient of Dr. Stephen Stein, a dentist in Denver and Highlands Ranch, to get tested for HIV and hepatitis, Fox 31 Denver reported.

The department said Thursday it has sent 8,000 letters out to patients who could be at risk.  The officials said patients may have been exposed to HIV, hepatitis B and/or hepatitis C if they received intravenous (IV) medications under Stein’s care from September 1999 through June 2011.

“It was determined syringes and needles used to inject medications through patients’ IV lines were saved and used again to inject medications through other patients’ IV lines,” the health department said in a statement. “This practice has been shown to transmit infections.”

As of yet, there have been no reported infections linked to Stein’s offices.  Stein stopped practicing June 24, 2011, and his office Stein Oral and Facial Surgery has been closed.

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