The bacteria which infiltrate the pocket between the gums and the base of the teeth, making gums bleed, ultimately resulting in the falling of teeth may well be making hearts fail as well. According to a recent study conducted in a group of 1,372 Puma Indians in Arizona, those with periodontal disease were 2.7 times as likely to suffer a heart attack than those with healthy gums. The researchers led by Robert Genco, an oral biologist from the State University of New York, Buffalo, took up a study of this population in 1983 because very few smoked. While there were suggestions earlier that oral infection may be a risk factor for heart disease, scientists had difficulty ruling out the effects of smoking before this study.