Fewer than half the low-income kids enrolled in California’s dental insurance program see a dentist in any given year. That seems like a problem. Whether it is, though, is impossible to tell because of the state’s inadequate oversight of the program, known as Denti-Cal. According to a recent audit, the state doesn’t collect the data necessary to determine whether the kids who need care can get it. The state should start measuring the performance of Denti-Cal as if it really cares how well it’s working.