TULSA, Okla. — Health officials Thursday urged thousands of patients of an Oklahoma oral surgeon to undergo hepatitis and HIV testing, saying unsanitary conditions behind his office’s spiffy facade posed a threat to his clients and made him a “menace to the public health.”

State and county health inspectors went to Dr. W. Scott Harrington’s practice after a patient with no known risk factors tested positive for hepatitis C and the virus that causes AIDS. They found employees using dirty equipment, reusing drug vials and administering drugs without a license.

Harrington voluntarily gave up his license and closed his offices in Tulsa and suburban Owasso and is cooperating with investigators, said Kaitlin Snider, a spokeswoman for the Tulsa Health Department. He faces a hearing April 19 where his license could be permanently revoked.

“It’s uncertain how long those practices have been in place,” Snider said. “He’s been practicing for 36 years.”

The Oklahoma Board of Dentistry said the inspectors discovered a number of sterilization problems at Harrington’s offices, including the use of a separate, rusty set of instruments for patients known to have infectious diseases.

“The CDC (Centers for Disease Control and Prevention) has determined that rusted instruments are porous and cannot be properly sterilized,” the board said in a 17-count complaint against the dentist.

Officials are sending letters to 7,000 known patients of Harrington.

The letters urge the patients to be tested for hepatitis B, hepatitis C and HIV — viruses typically spread through intravenous drug use or unprotected sex, not occupational settings.

Harrington could not be reached for comment Thursday.

The CDC is consulting on the case, and agency spokeswoman Abbigail Tumpey said such situations involving dental clinics are rare.

The Dentistry Board said Harrington ran a clinic that didn’t ensure items were sterile. The clinic had different cleaning procedures for its sets of equipment, drug vials were used on multiple patients and the office had no written infection-protection procedure.

The Dentistry Board accuses Harrington of “being a menace to the public health by reasons of practicing dentistry in an unsafe or unsanitary manner.”

Harrington told officials he left questions about sterilization and drug procedures to his employees. “They take care of that, I don’t,” the board quoted him as saying.

The doctor is also accused of letting assistants perform tasks only a licensed dentist should have done, including administering IV sedation. Also, the complaint says the doctor’s staff could not produce permits for the assistants when asked for them.