Even many older U.S. residents with relatively high incomes have lost all of their natural teeth.
The U.S. Centers for Disease Control and Prevention (CDC) have reported that finding in a look at oral health data from the 2005-2008 National Health and Nutrition Examination Survey (NHANES).
Rather than simply asking U.S. residents to report on their own oral health, the NHANES researchers send dentists to look in survey participants' mouths.
One of the indicators the investigators looked for is edentulism, or loss of all natural teeth in people ages 65 and older.
The 2005-2008 edentulism rate for all older U.S. residents was 23%. The rate was 37% for people with incomes under 100% of the federal poverty level, 31% for people with incomes of 100% to 199% of the federal poverty level, and 16% for people with inomes of 200% of the federal poverty level or higher.
The high rate of edentulism among older people with relatively high incomes might be due partly to a lack of emphasis on preserving teeth that was common in some areas of the country in the mid-1900s.
But the researchers also found signs that some younger U.S. residents with relatively high incomes were affected by the kinds of gaps in dental care that could eventually lead to edentulism.
The researchers found that about 15% of U.S. residents with incomes of 200% of the federal poverty level or higher had untreated cavities.