Three former patients of a Denver-area dentist who sought testing after being warned about possible HIV and hepatitis exposure have tested positive for infection, state health officials announced Wednesday morning.

The three were patients of Dr. Stephen Stein between 1999 and 2011 and had received notifications because the dentist reused sedation syringes, according to the Colorado Department of Public Health and Environment.

The health department has asked thousands of Stein’s surgical patients to seek testing.

The health department cannot, however, directly link the positive test results to Stein, who is not currently practicing.

“This does not mean any of these positive results are linked to Dr. Stein’s dental practice,” health department spokesman Mark Salley wrote in a news release Wednesday morning.

A state health department investigation focusing on Stein confirmed the use of unsafe injection practices.

The health department urged patients “to get tested — and, if positive, to check with their health care provider for care.”

The department “will not know the number of people who get tested, only the number of positive tests that are reported.”

Stein practiced at offices in Highlands Ranch and Cherry Creek.