9NEWS tracked down Dr. Stephen Stein at his new house near George Washington High School in Denver Thursday night.
"I have no comment," Stein said at his door when asked to respond to state health department accusations he reused needles and syringes on at least 8,000 patients.
Someone inside his house then closed the curtains and turned off the lights.
Last month, the Colorado Department of Public Health and Environment accused Dr. Stein of re-using needles and syringes for days at a time on his patients over the course of 12 years from 1999 to 2011.
He had two practices, one in Denver and one in Highlands Ranch.
August 1, the state health department said it had three positive lab tests from his previous patients. There is no way to connect Dr. Stein to those positive test results the health department said.
A 9NEWS viewer, who wanted to remain anonymous, says her husband tested positive for hepatitis C.
The positive lab results for hepatitis C was shown to 9NEWS nearly two weeks after 8,000 people received letters from Colorado's Health Department about oral surgeon Dr. Stein.
The 9NEWS viewer's husband went to Dr. Stein for several procedures. During his last procedure, done September 2009, Dr. Stein pulled her husband's wisdom teeth.
She received a letter from the state, much like many of Dr. Stein's other patients, saying her husband should be tested.
The positive results for hepatitis C came from her husband's doctor's office. Hepatitis C is an infection caused by a virus that attacks the liver and leads to inflammation.
"Most people infected with the hepatitis C virus (HCV) have no symptoms," according to the Mayo Clinic's website. "In fact, most people don't know they have the hepatitis C infection until liver damage shows up, decades later, during routine medical tests."
The 9NEWS viewer said tests for HIV and hepatitis B came back negative for her husband.
A nurse at her husband's doctor's office said there was no definitive way to link the positive hepatitis C results to Dr. Stein's practice.
Past patients may have been put at risk if they were seen by Dr. Stein during these time frames and at these locations:
• September 1999 to June 2011 at Stein Oral and Facial Surgery, 8671 S. Quebec St., #230, Highlands Ranch, CO 80130
• August 2010 to June 2011 at Stein Oral and Facial Surgery, 3737 E.1st Ave., Suite B, Denver, CO 80206. Patients also were seen by Stein at this location but under the name, New Image Dental Implant Center.
For more information, please call CO-HELP at 1-877-462-2911 or visit http://www.cdphe.state.co.us/.
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