High rates of dental disease remain prevalent across the nation, especially in vulnerable and underserved populations. According to national surveys, 42 percent of adults with tooth or mouth problems did not see a dentist in 2008 because they did not have dental insurance or could not afford the out-of-pocket payments, and in 2011, 4 million children did not obtain needed dental care because their families could not afford it. In 2011, the Institute of Medicine reported that there is strong evidence that dental coverage is positively tied to access to and use of oral health care. For families without dental coverage, federally funded health centers may offer an affordable dental care option. Health centers are required to offer sliding fee schedules with discounts of up to 100 percent for many low-income patients. GAO was asked to examine dental services in the United States. This report describes (1) trends in coverage for, and use of, dental services; (2) trends in payments by individuals and other payers for dental services; and (3) the extent to which dental fees vary between and within selected communities across the nation. To do this work, GAO examined HHS national health survey data and national dental expenditure estimates, dental insurance claims data, and health center dental fees in 18 selected communities (based on census region, population, and dental claims volume). GAO also interviewed HHS officials and academic experts.