Oct. 23—FLORENCE, Ala. — Sometimes, in a quiet moment between appointments, Dr. Carson Cruise runs the financial numbers through his head. They make a cold but compelling case: If he dropped all of the Medicaid patients from his small-town pediatric dental practice, he could make the same money while working far fewer hours. Cruise, 36, owns a dental clinic in the picturesque Alabama town of Florence, home to the University of North Alabama, tucked into the rural northwest corner of the state. He and his wife have two little boys, ages 3 and 5. They sold their small family farm recently because it became too difficult to keep up with it and his practice and still have time for their family. All of his patients are children. About half of them have their dental care covered by Medicaid, the joint federal-state health insurance program for people with low incomes. They come to his clinic from across the region, he says, and some parents drive from rural communities an hour away. He's got a waitlist four or five months long. "I have great relationships with a lot of these families I've been seeing for years," he said. "I don't want to leave them hanging, but it's getting to a point where it's really difficult to keep working at the pace we're working and seeing the volume that we're seeing." Even though more than half of Alabama children are enrolled in Medicaid, Cruise said he is the only board-certified pediatric dentist in the area who still accepts it. Alabama is a vivid example of a national problem. Most state Medicaid programs pay dentists far less than private insurers do for the same services. As a result, not enough dentists are willing to take Medicaid patients, leaving low-income families in Alabama and many other states with limited options for providers and longer wait times when they find one. Alabama has fewer dentists per capita than any other state except Arkansas, according to the American Dental Association. A handful of Alabama counties lack any dentist at all, while other areas — including parts of Lauderdale County, where Cruise's clinic is located — are considered dental deserts, places where patients have to drive at least half an hour to reach a clinic. The problem is likely to get worse: In several counties, more than half of dentists are 60 or older, while nearly half have no dentists under age 40. States have flexibility in how they structure their Medicaid programs, including in how much they reimburse providers. Alabama Medicaid reimburses dentists about 46% of what they charge, on average, for their services. The state pays so little for some procedures, Cruise said, that dentists lose money by providing them. Some dentists decide that treating Medicaid patients just isn't worth it. That helps explain why, even though Alabama children get cavities at rates similar to children nationwide, they are less likely to be treated for them.