TOMAH, Wis. -

Nearly 600 veterans are at risk after a dentist working for the Tomah VA failed to follow the medical center’s standard infection control procedures for a year. The medical center is offering free screenings for veterans to test for the infections  hepatitis B, hepatitis C and HIV.

Although experts say the risk of infection is very low, the VA is notifying all the patients of a dentist, who they are not naming, who allegedly failed to properly sanitize what is called a dental bur according to VA standards.

This comes at a time when the Tomah VA is working to better the medical center, which has come under fire for reports of over-prescribing medication and a negative work environment.

"There was culture issue here, one of non-psychological safety, one of opioid abuse,” the center’s acting director, Victoria Brahm, said. “Those things are changing."

Part of that change, Brahm said, is weeding out employees that put veterans at risk, like the dentist who she said knowingly went against the VA's standards from October 2015 to October of this year.

Brahm said the dentist had one assistant for most of the time, but it was a different assistant who reported the issue.

"He had a replacement dental assistant, and she noted this particular piece of instrument being used,” Brahm said. “She reported it the next day, Oct. 20, to the dental chief who reported it to senior leadership. We took action Oct. 21."

The VA requires dental burs to be disposable.

"He brought in his own burs and cleaned them with Virex solution, salt and a wipe which is nothing we endorse,” Brahm said.

Not only is that against VA standards, but the president-elect of Wisconsin's Dental Association, Dr. David Clemens, says that's no longer general practice.

"When I first started doing dentistry in 1980, that was considered acceptable,” he said.”The only way to make sure you've killed all the bacteria is to put it through a sterilization or autoclave."

The VA removed the dentist from clinical care, and is referring the case to the Office of Inspector General for an assessment of possible criminal charges

"During all of the orientation, he used our equipment. He used it appropriately, so it was very purposeful,” Brahm said. “From what we found in our investigation, he knew exactly what he was doing and preferred to use his own equipment against procedure."

The dentist's assistant who didn’t come forward is also under VA administration investigation for not bringing the matter to administrators. Brahm said administration has made changes, so now dentists' assistants rotate.

All 592 veterans are being notified by the Tomah VA, either by letter, or in the case of 54 who had bridge or crown work, by phone call.

Dr. Clemens said those who had bridge or crown work would be slightly more likely to get infected, but again, that risk is still low.

There have been no reports of anyone becoming infected.