More Americans are turning to the emergency room for routine dental problems—a choice that often costs 10 times more than preventive care and offers far fewer treatment options than a dentist's office, according to an analysis of government data and dental research. The number of ER visits nationwide for dental problems increased 16 percent from 2006 to 2009, and the report released Tuesday by the Pew Center on the States suggests the trend is continuing. Pew researchers analyzed hospital information from 24 states, and data from the federal Agency for Healthcare Research and Quality and studies on dental care.