Dr. Fred Clark checks out a student as part of the the Deamonte Driver Dental Project in Largo in November. The project is named for a boy who died due to complications from a lack of dental care. (Michael S. Williamson/The Washington Post)

Donald L. Chi is a pediatric dentist and an associate professor at the University of Washington School of Dentistry. He is also a fellow at the Center for Advanced Study in the Behavioral Sciences at Stanford University.

In January, Vadim Kondratyuk, a 26-year-old truck driver from California, died suddenly after harmful bacteria from a cavity spread to his lungs. He left behind a wife and two daughters.

Cavities are a serious but overlooked problem in the United States. About half of all childrenhave cavities, making them the country’s most common childhood disease. Unfortunately, health proposals under consideration by the Trump administration and Republican leaders in Congress could make the situation worse, with devastating consequences for millions of poor Americans.

Untreated cavities lead to toothaches, keep kids out of school and reduce learning. They also diminish workers’ economic productivity. Even babies are not immune. I have performed countless extractions of the four front teeth on infants barely a year old. The teeth look like burned tree stumps and cream-colored streams of pus often ooze from the gums, signaling infection. These infants are almost certainly in pain, but since they cannot speak, the only clue that there is a problem comes when a parent notices a child is not eating or sleeping normally.

This may surprise readers who have never had a cavity or who have had cavities but could easily get them treated. Most middle- and high-income Americans are protected. We can afford healthy, low-sugar foods. We brush with fluoride toothpaste. We get regular checkups using insurance that helps pay for treatment.

The poor do not always have these luxuries.

A reckless repeal of the Affordable Care Act would put more than 6.7 million adults at risk of losing dental coverage. Under current law, adults can receive dental coverage if their state offers it under Medicaid; if they purchase stand-alone, nonsubsidized dental plans on ACA exchanges; or if they buy an ACA marketplace health plan with a dental plan included. An estimated 5.4 million adults were insured through the ACA’s Medicaid expansion, and another 1.3 million purchased stand-alone dental benefits plans. That doesn’t include the number of adults who purchased ACA marketplace plans with dental coverage, which is unknown.

House Speaker Paul D. Ryan’s (R-Wis.) plan to use block grants to fund Medicaid is designed to cut costs and give states greater flexibility to run the program. But unlike today’s Medicaid, a block-grant program would not automatically expand when the number of people who need the program increases, which happens whenever a recession throws more people into poverty.

Block grants would force states to make tough decisions, and adult dental care would undoubtedly end up at the bottom of states’ spending priorities because it is an optional Medicaid benefit. This happened during the Great Recession in states such as California, Massachusetts and Washington, where legislatures axed dental benefits for the poor. There were immediate one-time savings, but emergency room visits for patients with toothaches eventually began skyrocketing, increasing overall health spending.

Under block grants, even poor children in Medicaid could lose comprehensive care guaranteed under the child-health component of the program. States could decide to cut benefits and introduce copayments, annual caps and prior authorization requirements for treatment — all of which would hurt the neediest children in the United States.

What can we do to make sure everyone has a chance at good oral health?

First, dental care needs be recognized as an essential benefit. That means including comprehensive dental coverage in Medicaid and the ACA as well as in Medicare (where it is excluded). It means repairing the ACA and expanding it, not killing it. And it means keeping Medicaid as an entitlement — not a block grant — and preserving health-care benefits for low-income children.

Comprehensive dental coverage would give poor adults a chance to get needed fillings, root canals, caps and dentures. Sure, this will require funding, but it would also be an investment. Fewer emergency room visits would result in cost savings. Adults with healthy mouths could also find meaningful work without the fear of appearance-related discrimination, which is hard to avoid when you have rotting or missing front teeth. And, of course, there would be less suffering.

State policymakers also have a role: They should invest in dental programs within Medicaid for vulnerable subgroups, such as babies and children with special needs. In Washington state, the Access to Baby and Child Dentistry (ABCD) program trains dentists to manage infant behaviors and expands benefits (for example, by paying for four fluoride treatments instead of two per year) and boosts dentist reimbursement rates. The success of ABCD has led other states to set up similar initiatives. The rest should do the same.

Ten years ago, 12-year-old Deamonte Driver, an African American child in Maryland, also died because of a cavity. As a fitting tribute to Deamonte, Vadim and their grieving families, we should make sure no more Americans suffer this unnecessary tragedy.