Updated

Police on Friday were investigating allegations of prescription fraud against a dentist also accused of possibly exposing patients to HIV and other infections by reusing syringes and needles.

Police began their probe of the allegations against Stephen Stein after the state attorney general's office contacted them and the Denver district attorney's office in April, The Denver Post reported.

The allegations of prescription fraud are apparently separate from accusations that Stein's practice re-used medical instruments.

No working phone number could be found for Stein.

Police and prosecutors said they did not know whether the prescription fraud inquiry would expand to include a criminal investigation of the allegations that Stein's practice reused syringes and needles for patients getting intravenous drugs.

State health officials said Friday it was too early to tell if anyone has been infected by the alleged reuse of the instruments.

No specific infections have been linked to Stein's practice, said Dr. Chris Urbina, executive director of the Colorado Department of Public Health and Environment.

The dentist operated Stein Oral and Facial Surgery from September 1999 until June 2011, first in Highlands Ranch, a subdivision south of Denver, then in Denver. His attorney, Victoria Lovato, said Stein was cooperating with state officials.

Letters were mailed Thursday to at least 8,000 patients advising them to be tested for hepatitis B, hepatitis C and human immunodeficiency virus, or HIV, the virus that causes AIDS, if they received intravenous drugs under Stein's care. It remained unclear how many received injections.

Former patient Shannon Stamey told KMGH-TV that she saw Stein for a dental implant in 2008 and found out about the allegations through a posting on Facebook. She has tested negative for HIV and hepatitis.

"I immediately, actually, began shaking," she said as she recalled her anger. "I don't really understand how someone could do that or why you would do that, and why no one would speak up for 12 years."

Stein is not currently practicing. He entered an interim cessation of practice agreement with the state Board of Dental Examiners in June 2011.

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