Approximately 500 million dental visits occur each year in the United States, and they come at a hefty price. According to a 2015 report,1 dental care represented 4% of the total US health care costs. As noted in this report: "Spending for dental services increased 4.2 percent in 2015 to $117.5 billion, which was an acceleration from 2.4 percent growth in 2014. Out-of-pocket spending for dental services (which accounted for 40 percent of dental spending) increased 1.8 percent in 2015 after increasing 0.8 percent in 2014. Private health insurance (which accounted for 47 percent of dental spending) increased 3.0 percent in 2015 following 2.1 percent growth in 2014."

Dental caries, commonly known as tooth decay, is an oral disease in which the acid generated by oral bacteria cause damage to hard tooth structure. Although preventable, it is one of the most common chronic, infectious diseases among American children and adults, and remains one of the most common diseases throughout the world. In spite of major improvements that have been made in the US dental health care system over the past few decades, particularly with regard to the percentages of cavities found in both children and adults, some population groups continue to experience caries at higher rates than others. This is particularly true for populations with lower income and lower education and also for some ethnic and racial groups.2