Medicare Advantage plans and stand-alone private dental insurance plans may be helping more older Americans keep their teeth.

The percentage of Americans age 65 and older who were missing all of their natural teeth fell to 26% during a 2004-2007 survey period, down from 27.6% in 2000-2003.

Older Americans who owned private health insurance, such as Medicare supplement or Medicare Advantage coverage, started out with better oral health and showed a similar level of improvement. The percentage of private insured older Americans who were “edentulous”–toothless–fell to 22.5%, down from 24.1%.

Charlotte Schoenborn and Kathleen Heyman, researchers at the National Center for Health Statistics, published those figures in a new report on the overall health of U.S. residents ages 55 and older. The researchers drew on results from 36,984 interviews conducted for the 2004-2007 National Health Interview Surveys, and also on 2000-2003 NHIS data.

One factor with an obvious correlation with dental health is income: U.S. residents ages 65 and older who are “not poor” are about twice as likely to have some of their natural teeth as comparable low-income residents, according to the NHIS data.

Age is another key factor.

In part because oral health tends to deteriorate with age, and in part because of changes in dentistry, 32% of privately insured U.S. residents ages 85 and older are missing all of their teeth, compared with just 8% of privately insured U.S. residents ages 55 to 64.

Some of the recent improvement in older Americans’ dental health may be due to use of dental benefits to pay for preventive care.

Overall, “the percentage of older adults who have visited a dentist in the past 12 months declines steadily with age,” Schoenborn and Heyman write.

But older Americans are visiting the dentist more often: 64.7% reported during the 2004-2007 interview series that they had been to the dentist in the previous 12 months, up from 62.9% in 2000-2003, and up dramatically from 43.2% in 1989.

The very oldest Americans are making faster gains. For privately insured adults age 85 and older, the percentage who had been to the dentist recently jumped to 56.3% in 2004-2007, up from 52.4% in 2000-2003, and up from less than 36% in 1989, Schoenborn and Heyman report.

The basic Medicare program does not provide dental benefits. The NHIS team did not ask survey participants about whether they owned dental coverage.

But researchers from Mathematica Policy Research Inc., Washington, note in a report prepared for the AARP Public Policy Institute, Washington, that 37% of 2008 Medicare Advantage enrollees were in plans that provide preventive dental benefits. “About half of these had a package that included at least one exam and cleaning every 6 months and at least one X-ray per year,” the Mathematica researchers write.

The percentage of Medicare Advantage enrollees with dental benefits has probably increased to 44% this year, and the percentage of MA plans offering preventive dental benefits has increased to 57%, from 36% in 2008, the researchers write.

Schoenborn and Heyman have published data that shows an interesting shift in men’s use of dental services.

From ages 55 to 74, women are somewhat more likely to visit the dentist. But men who survive to enter the 75-84 age group are almost as likely as the women in that age group to have been to the dentist in the past year, and men who reach 85 are more likely than the women in that age group to have been to the dentist.