Not everyone goes to the dentist like they should, and many children and families haven't seen a dentist in years, which can lead to significant health issues.

According to the National Academies, millions of Americans are not receiving needed dental care services because of "persistent and systemic" barriers that limit their access to oral health care.

The report says that economic, structural, geographic and cultural factors contribute to this problem. For example, approximately 33.3 million people live in areas with shortages of dental health professionals. In 2008, 4.6 million children did not obtain needed dental care because their families could not afford it. And in 2006, only 38 percent of retirees had dental coverage, a benefit not covered by Medicare.