Visits to the dentist can be upsetting for little children, but when Autum Archuleta took her son Nathan to a Small Smiles dental clinic in February 2010, it was beyond anything she could have imagined. The dentist gave Nathan, then almost 3, three crowns, two baby root canals and six silver fillings in 25 minutes.

While in the waiting room, Archuleta says she heard her son screaming and burst into the treatment room. She says Nathan was crying and struggling to move while being held down by three clinic employees and wrapped from his head to his feet in a stabilization device called a papoose board. She thinks he wasn't properly numbed.

"He wasn't the same for a long time after we brought him home," Archuleta said. "He cried a lot...He wasn't my little boy. He didn't smile...The night terrors were the worst. I mean it was a lot of sleepless nights."

A dentist who later reviewed Nathan's records said the work was shoddy and many procedures unnecessary. A dentist who saw Nathan the following year wrote that he had "severe situational trauma."

"To me I think they did it for the money," Archuleta said of Small Smiles. "Flat-out did it for the money. Because it was Medicaid and Medicaid would pay them."

An NBC News investigation of the performance of Small Smiles' 63 dental clinics over the last three years found repeated allegations of substandard work and unnecessary procedures which drove up the cost to taxpayers. The allegations came from anguished parents, government investigators and former employees around the country.

Such practices violate a settlement the company reached with the Justice Department in January 2010, following allegations that it was bilking taxpayers by doing unnecessary and substandard procedures on low-income children.  

At the time, Tony West, Assistant Attorney General for the Civil Division of the Department of Justice said, "We have zero tolerance for those who break the law to exploit children in need."

The company that managed Small Smiles and affiliated clinics agreed to significantly alter its practices and subject itself to independent monitoring. It also agreed to pay $24 million, without admitting wrongdoing.

But three years later, records show the company has not cleaned up its act.  

"This company sees dollar signs in the eyes of every child they bring in," Senator Chuck Grassley told NBC News. Grassley has been investigating dental organizations whose primary source of revenue is Medicaid. He says Small Smiles practices assembly-line treatment, focused more on quantity than quality.

"This whole investigation kind of leads us to two things. To a conclusion that the tax payers are being fleeced, and children are being abused." Grassley said.

Small Smiles clinics are managed by a private corporation called CSHM, LLC, which was until June called Church Street Health Management. 

The Department of Health and Human Services Office of the Inspector General (HHS OIG) is responsible for monitoring the clinics and rendering penalties when appropriate.

Lisa Re, a branch chief who heads an HHS OIG team of attorneys, says CSHM is improving since it emerged from bankruptcy in June 2012 with a new CEO and leadership.

"Recently, under new management, I would say that it is getting much better."

But according to letters from HHS OIG to Church Street, the compliance has been inconsistent and sometimes alarming.

In May, the office required CSHM to temporarily close a facility in Oxon Hill, Maryland to train staff on "the appropriate use of mouth props, patient stabilization practices, appropriate use and administration of anesthesia," among other things. Nine of 30 records the independent monitor reviewed "did not provide any documentation or radiographic evidence to support the medical necessity for the treatment provided. Six of those nine records showed baby root canals were performed "without medical necessity."

The OIG required the company to divest from a location in Manassas, VA in March because of "flagrant violations." A 2011 audit at that clinic found 104 of 244 baby root canals performed by the lead dentist to be medically unnecessary. In a sample of 34 records, 20 patients were restrained and given baby root canals with insufficient anesthesia. The monitor expressed concern that the children "were resisting treatment because they were being hurt."

In June the office fined CSHM 100,000 dollars after an audit found multiple breaches at an Ohio clinic, including treatments performed without medical necessity, incomplete or poorly done root canals, crowns places on "non-restorable" teeth and "poor techniques of administering local anesthesia." Six of seven dentists performed root canals on children that were not needed.

Last year, the agency issued a 230,000 dollar penalty, the largest it has ever levied, for multiple failures to comply with provisions of the government agreement. Among the breaches, the company failed to meet training and education requirements.

Still, Small Smiles continues to rake in millions in Medicaid dollars. Despite multiple threats to exclude the company from receiving federal funds, it made 150 million dollars in revenue from Medicaid in 2011.

The HHS OIG has given Church Street multiple chances to keep the clinics in business, levying penalties against the company and threatening to exclude them from receiving federal dollars. But the threats generally come with an out — a way to repair the breaches and avoid being exclusion.

Senator Grassley believes that cycle should come to an end.

"The inspector general has given this group a lot of second chances. Every time they get their hand in the cookie jar. All sorts of excuses. So you get back to how long can this go on — the fleecing of the tax payers, the abuse of children? And you get back to the point that maybe it's about time for the inspector general to disqualify this company from Medicaid."

DENTAL CARE VACUUMS CREATE LIMITED OPTIONS IN LOW-INCOME NEIGHBORHOODS

Small Smiles treats about 500,000 children a year. Jamier Brown, 4, was one of them. His mother Jasmine brought him to Small Smiles in Dayton, Ohio at the end of 2011 because she couldn't afford her other options. 

"I knew that his mouth needed attention. And he was complaining that his teeth were hurting, so I just couldn't wait around to see when I could get the money. I had to go as soon as I could," she said.

Jamier received caps and fillings in most of his mouth in January.  Months later, he is still in pain.  The gum line is discolored where his front teeth we capped and Jamier says, "It hurts all the time."

Two dentists who reviewed Jamier's records said he should have been treated by a pediatric dentist, most likely in the hospital under general anesthesia. One called the treatment on his front teeth "inadequate."

At the time Jamier was treated, Jasmine was in Job Corps and living with her mother. She blames herself for what happened to her son. 

"It's kinda my fault," she said as tears rolled down her face, "Because if I would have had the money, he probably wouldn't have felt any of that pain that he had to go through."

The guilt Brown feels is common among parents who spoke with NBC News and claimed their children were hurt at Small Smiles. They all said they didn’t know where else to go.

According to the Centers for Medicare and Medicaid Services, 31.5 million children were eligible for dental coverage through Medicaid in fiscal year 2011, but only 14.7 million children utilized a dental or oral health service.

Four out of five dentists don't take Medicaid, some because they just don't treat children but others complain of low reimbursement rates. Dr. Warren Brill is the president elect of the American Academy of Pediatric Dentistry (AAPD). He has his own practice in Baltimore, MD and 85 percent of his patients are on Medicaid. 

"Reimbursement rates are a large factor in terms of dentists not accepting children on Medicaid, because the fees that they get are often times lower than the cost of providing the care," he said.

According to AAPD 70 percent of its members accept Medicaid. But only 3.5 percent of all professionally active dentists practice that specialty.   

Nevertheless, Dr. Brill says parents of children on public insurance can find quality care.

"It's a question of learning how to make the appointment, getting referrals from state health departments, from dental associations, from friends and relatives. Parents that find those avenues should be able to find a dentist for their children."

DOES PROFIT MODEL PUT CHILDREN AT RISK?

Because Medicaid reimbursement rates are lower than what dentists charge other patients, critics say to make a profit, the clinics rely on volume.

Dr. Kianor Shah worked for Small Smiles briefly in 2011.  He says he left after witnessing disturbing practices. The dentist showed NBC News notes he took about treatments he observed during his time there. Scattered across several pages were words like "restraint brutal," "unnecessary" and "no way."

"I observed excessive use of the papoose board and excessive use of force to restrain children as well as overtreatment for procedures that could have been done with much less invasive approach."

Shah claims dentists were coerced into abusing children and overcharging Medicaid by the promise of bonuses and pressure from management. 

"I was advised, quote unquote, 'The dentists eat what they kill.' That means that they're gonna get paid for as much work as they do on those Medicaid kids. And that was about the last straw for me."

Senator Grassley's investigation involves dental management companies that are controlled by corporate investors. Many states require dentists to own the clinics but the management companies, like CSHM, effectively control the operations.

"Our investigation has found a lot of private equity money being invested in companies that are doing everything they can in the most sophisticated way to take as much money out of Medicaid as they can. And in the process of just milking the Medicaid program, we're finding a lot of abuse of children."

PROGRESSIVE IMPROVEMENT AT SMALL SMILES

The Inspector General's office says the Small Smiles clinics have progressively improved, and while that improvement has been "uneven," the company is providing essential care to a vulnerable population. The agency maintains that it is better to aggressively monitor the company than to shutter it.  

"If we had closed down Small Smiles last year, there would have been an uncontrolled shut down of this company leaving half a million kids scrambling for dental care," said Lisa Re.

The issue is further complicated by the states, which are responsible for administering Medicaid. The OIG surveyed states about the impact of closing the clinics and got a strong reaction.

"Some of the states were alarmed that we were even considering closing any of the clinics because they simply didn't have enough dentists to provide any care to these kids," said Re.

The attorney said in the last couple of years the office found five clinics to have the most significant problems.

"It's important to understand that not every clinic is providing bad care. If that were the case, this is an easy decision."

According to an affidavit in the Church Street bankruptcy filing earlier this year, "more than 1.5 million patients have been served during the past five years, improving overall dental health and access to care in many low-income areas in the 22 states in which the Company has had a presence."

Chris and Loretta Trujillo are grateful for the care the Small Smiles in Denver provides their children. They say it is very difficult to find dentists who take Medicaid and their children, Jordan, Jazmin and Faith, have never had a bad experience.

"My kids have never been scared coming here," said mom Loretta. "They're excited to come."

The Inspector General's office is taking on Small Smiles on a clinic-by-clinic basis, vigorously monitoring them and assessing penalties when appropriate.

"We have taken targeted and aggressive action against the clinics that provided bad care while allowing the company to provide good necessary care at the other clinics," she said, adding that the clinics are showing marked improvements since a new CEO, David Wilson, came on in June.

"The company as it operates today is simply not the same as the company that was repeatedly violating the agreement," Re insists.

In a statement to NBC News, CSHM's Wilson wrote, "Patients are at the center of everything we do at CSHM. CSHM LLC supports our affiliated dental centers so that they can continue to provide access to quality dental care. Our dental centers serve approximately one million patient visits per year, primarily to children in communities with under-served access to dental care." 

Following an alarming audit of the Small Smiles clinic in Youngstown, Ohio that found substandard and unnecessary care, the new management company, which had just been formed, fired nine dentists there. The Inspector General's office called that action encouraging.

CSHM stressed its commitment to quality care. "Under the new management team, more than 50 new dentists have joined CSHM affiliated centers and the company continues to support their ongoing efforts to recruit qualified dentists."

That is simply not enough for Jasmine Brown. "I don't want anybody else's child to have to go through what my son went through, especially being that young. That's traumatic. That's something that could follow him the rest of his life."

Jasmine is now holding down two jobs — one as a pharmacy tech at CVS, the other as a security guard at a men and women's shelter. She says she can now afford to get Jamier the care he needs. 

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