DENVER (AP) -- State health officials allege a Colorado dentist reused syringes and needles to administer drugs to patients, possibly exposing them to the virus that causes AIDS or to hepatitis.

The Colorado health department said Thursday no specific infections have been linked to the offices of the dentist, identified as Stephen Stein.

Stein's attorney, Victoria Lovato, didn't immediately return a call seeking comment.

It wasn't clear when alleged practice started but officials say it didn't continue past June 2011.

Also unclear is how many patients might be involved. Officials say anyone who received intravenous drugs under Stein's care between September 1999 and June 2011 may have been exposed to human immunodeficiency virus or HIV, hepatitis B or hepatitis C.

Health officials say Stein isn't currently practicing.

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