TOMAH, Wis. -- A dentist has resigned from his position at a Wisconsin Veterans Affairs hospital amid accusations he treated hundreds of patients with improperly cleaned equipment.The VA in Tomah, Wisconsin, announced the dentist's resignation Friday, ahead of a scheduled Monday meeting of a panel used in situations that could warrant firing.The hospital's acting medical director, Victoria Brahm, said last week that an investigation was launched after a dental assistant reported last month that the dentist hadn't properly cleaned equipment. Brahm says the dental equipment might have been cleaned, but it didn't meet VA standards.The dentist's name wasn't released.Brahm says 592 veterans who received care from the dentist can receive free screenings for hepatitis B, hepatitis C and HIV. She says the risk of contracting an infection is low.