The Colorado Department of Public Health and Environment is warning patients who went to a local oral surgeon over the past decade to get tested for HIV and hepatitis, after the doctor had been found to reuse needles for procedures on multiple patients.

CBS Denver reports that Dr. Stephen Stein may have reused needles on multiple patients between September 1999 and June 2011, potentially exposing patients to HIV, hepatitis B and/or C or other bloodborne diseases.

According to the Colorado health department, Dr. Stein re-used syringes and needles during oral and facial surgery procedures, and for intravenous (IV) medications, including for sedation.

"Needles and syringes were used repeatedly, often days at a time," the department said in a "Frequently Asked Questions" document posted on its website. "Because there can be a small amount of blood that remains in syringes and needles after an injection through an IV line, there is a risk of spread of bloodborne viruses, such as HIV, hepatitis B, and hepatitis C, between patients."

According to CBS Denver, Stein is a licensed dentist who practiced oral surgery at Stein Oral and Facial Surgery in Highlands Ranch, Colo. from September 1999 through June 2011 and at an office of the same name from August 2010 to June 2011 in Denver. Stein also saw patients at the office under the clinic name of New Image Dental Implant Center.