Zachary Feinberg went to a mobile dental clinic in Roseville last week for his first checkup in six years. So the 14-year-old wasn’t surprised when the dentist he dubbed “Captain Hindsight” told him he’d need two fillings and a root canal.

“ ‘You should have brushed more,’ ” he said, imitating the dentist. “I was expecting it.”

Like the Stillwater teen, the state received a troubling checkup last week in a report that found that more than a third of Minnesota’s poor children receive no annual dental checkups.

Help could be on the way in the form of MNsure, the state online insurance exchange that launches next month. Because federal policy requires the exchange to include pediatric dental benefits, state officials expect that thousands more Minnesotans will buy coverage and seek long overdue care for their children’s teeth. But they also caution that this expansion of benefits won’t solve all of the state’s dental woes: Many of the neediest children already qualify for state-subsidized dental benefits and don’t use them.

“We need to do more to provide dental care to low-income children. There’s no question about it,” said Merry Jo Thoele, who coordinates oral health planning for the Minnesota Department of Health.

A reminder of that need came from the Commonwealth Fund last week, which ranked Minnesota last in the nation for the rate of low-income children receiving annual dental and medical care. The ranking was based on the 2011-2012 National Survey of Children’s Health, which showed that one in three children living at or below 200 percent of the federal poverty level in Minnesota didn’t receive annual dental checkups, even though they were already eligible for coverage from state-subsidized health care programs.

In its first oral health plan, released this January, the state Health Department issued a goal of increasing the number of children receiving preventive dental care by 10 percent. The agency also listed strategies that could help low-income families, including making greater use of midlevel dental providers and dental hygienists — who under collaborative practice rules can perform basic cleanings and treatments in schools and satellite clinics without dentists looking over their shoulders.

The state also wants to continue to increase the number of school-based dental programs through such organizations as Children’s Dental Services of Minneapolis, which currently works with more than 100 school districts.

“When you think about the barriers low-income people have, one of them is missing work to get to an appointment,” said Sarah Wovcha, the nonprofit’s executive director. “We eliminate that barrier by getting the care directly to the school where the kids are.”

But state leaders and dentists agreed that the biggest dilemma right now is the low reimbursement rate from the state’s Medical Assistance and MinnesotaCare programs to dentists for treating low-income children. The state programs pay about 40 percent of what dentists typically charge.

Many dentists either refuse to treat low-income children covered by the state or take but a handful of them, leaving low-income parents frustrated as they try to schedule checkups for their kids.

Feinberg ended up at the Ucare mobile dental lab in Roseville only because he is covered by Medical Assistance and his grandmother, Judy Johnson, couldn’t find a dentist at home in Stillwater who would accept him.

“It just seems to me that dental care is for the privileged,” she said.

The Minnesota Department of Human Services is reviewing how much it pays dentists after a legislative audit cited the high number of dentists refusing to treat children covered by state health plans. A 5 percent rate increase is already scheduled for 2014, but that likely won’t be enough to lure more dentists back to treating these children, said Scott Leitz, an assistant commissioner for the department.

The MNsure exchange will include medical assistance plans but also new private plans that could be attractive to working families who don’t qualify for state assistance and couldn’t afford dental coverage for their kids before.

“The research is clear that you go twice as often to the dentist if you have some form of insurance,” said Sheila Riggs, who directs the primary care program at the University of Minnesota School of Dentistry. “So more kids having coverage is going to be good.”

A question for dentists is whether the new private plans will pay them at commercial rates or public-program rates. If the plans have low reimbursements, dentists might not take their patients, either.

“We don’t know what we’re getting,” said Dr. Mike Perpich, president of the Minnesota Dental Association.

Commonwealth’s last-in-the-nation ranking of Minnesota surprised dental profession leaders because another health policy organization, the Pew Charitable Trusts, recently gave the state an “A” grade for pediatric dental care, also noting however that the state has a “problem” in the high number of low-income children who don’t receive regular checkups.

Improved payment rates will help, but state leaders said they also need to make dental care more convenient for low-income families. Organizations such as UCare and the Ronald McDonald House Charities are helping by operating mobile clinics that visit areas of the state where dentists are in short supply.

“For the people we are trying to target, you have to bring the clinic to them,” said Dr. Michael Sudit, a Wayzata dentist who is trying to create a similar mobile clinic through the Molar Express organization he founded.

Outreach helped Feinberg, the 14-year-old who received a checkup last Monday and two fillings when he returned Friday.

His last previous dental visit had been so long ago that he remembered extorting a “Star Wars” toy out of his mother if he agreed to go. Since then, he has ignored dental problems and had even stopped chewing on one side of his mouth.

The pain of Friday’s fillings was offset by the joy of missing geometry class. But next up is the root canal. While his grandmother is relieved he is receiving overdue care, Feinberg is nervous about the procedure. Maybe this time he’ll hold out for a better toy.