Five-year incidence of tooth loss in Iowans aged 65 and older.

The prevalence of missing teeth has been described for US adults, but little is known about the incidence of tooth loss in any segment of the population. This study investigated the 5-yr incidence of tooth loss in a random sample of Iowans aged 65 yr and older residing in two rural counties. These people had an average of 20 teeth at baseline and approximately 40% lost at least one tooth in the subsequent 5 yr. The incidence of tooth loss was highest for mandibular molars and lowest for mandibular canines. Men were more likely than women to lose teeth. Although we were able to identify a number of statistically significant potential risk factors for tooth loss, the multivariate models that incorporated all these factors were not good predictors of which people were at highest risk for tooth loss.