A dentist in Tulsa city in the U.S. state of Oklahoma may have exposed as many as 7,000 patients to hepatitis B, hepatitis C and HIV since 2007, state officials said Thursday. Health officials are urging the some 7,000 patient of Oklahoma dentist W. Scott Harrington to be tested for HIV and hepatitis in an ongoing investigation with the state board of dentistry, according to FOX news. The possible exposure reportedly happened at the dental practice of Harrington in Tulsa and Owasso in Oklahoma, and officials are sending letters to 7,000 patients who have visited the facility since 2007. Harrington had a high volume of patients who were diagnosed hepatitis or HIV, and he allegedly violated sanitation laws among others, Susan Rogers, the Executive Director of the Oklahoma Board of Dentistry, said Thursday. An investigation into Harrington\'s practice found numerous violations of health and safety laws and major violations of the State Dental Act, officials said. Dental Board investigators have been assisted by agents from the Oklahoma Bureau of Narcotics and the United States Drug Enforcement Administration concerning the maintenance, control and use of drugs on the premises, according to the board. Harrington is facing 17 allegations from the Oklahoma Board of Dentistry due to health and safety violations levied against his practice, according to the news website NewOn6.com. Health authorities noted that transmissions of these diseases in this type of occupational setting is rare