The Dutch dentist was initially welcomed to the rural French town of Chateau-Chinon, which had been without a dental care provider for two years.

Then the horror stories started.

Now Jacobus Van Nierop is standing trial on charges of aggravated assault and insurance fraud, after scores of patients said he caused them injuries since arriving in town in 2008, Agence France-Presse reports. If found guilty, he could be sentenced to as many as 10 years in prison and fined up to $165,000, according to AFP.

The Associated Press has this account from a woman who said she was treated by the "Dentist of Horror," as he has been dubbed in French media:

"One patient, Sylviane Boulesteix, has said she was unexpectedly summoned to the dental office in central-eastern France in May 2012. Without warning, the dentist pulled eight of her teeth out and immediately fixed dentures on her raw gums. For three hours, the elderly woman says she sat gushing blood."In the following days, she says Van Nierop refused to relieve her pain. A judicial expert later described a 'cruel and perverse' man whose incompetence made Boulesteix lose several health teeth, go through trauma and suffer irreversible damage to her mouth."

According to AFP, some patients said they would wake to find notes asking them to come back for further treatment:

" 'Every time, he would give us what he called 'a little prick' and we were asleep, knocked out,' said Nicole Martin, a retired teacher who lost several teeth to abscesses caused by the horrific operations." 'When it was over, we would find a Post-it note saying to come back for an appointment the next day or the day after,' she added."

Martin set up a victims' group to press charges that grew to more than 120 members, according to AFP.

Van Nierop, 51, has said he "suffers from 'psychological problems' including gender identity issues and suicidal tendencies," AFP reports.

He had a blanket over his head when he arrived today at the courthouse in the nearby city of Nevers, AFP reports. He has been incarcerated for the past 18 months.

"What my clients and I expect are explanations," Charles Joseph-Oudin, who is representing some of the victims, tells AFP. "To understand how Mr. Van Nierop could have acted in such a way for so long, how things could have become so bad. Today, we have no explanations. Understanding is the first step of the victims' healing process."

According to the AP, the defendant has "refused to answer questions during the investigation, saying only that the oral health of the people in the region was 'deplorable.' "

Van Nierop was arrested in 2013 but was released and then fled to Canada, AFP reports. He was found in New Brunswick in 2014, extradited to the Netherlands and then sent back to France to stand trial.

Copyright 2016 NPR. To see more, visit