BACKGROUND: Chronic periodontitis (CP) has been associated with cardiovascular diseases. The study purposes were to identify the odds of acute myocardial infarction (AMI) and CP defined at different thresholds.

METHODS AND RESULTS: We studied 80 subjects with clinically confirmed AMI and 80 matched control subjects with no evidence of cardiovascular disease all receiving a comprehensive periodontal examination. Statistical analysis demonstrated a difference in the proportion of sites with a periodontal probing depth >/=6.0mm (2.7% for non-AMI and 12.1% for AMI group, 95% CI: -2.8 to 0.01, P<0.05) but no difference in the extent of gingival bleeding was found between groups. The odds ratio of having AMI and periodontitis varied between 9.2:1 to 14.1:1 with the greatest odds ratio if bone loss exceeded 4mm at >/=50% of the teeth (OR: 14.1:1, 95% CI: 5.5 to 28.2, P<0.0001). The odds ratio remained significant also when only non-smokers were considered (51 subjects) (OR: 7.0:1, 95% CI: 2.0 to 24.3, P<0.01).

CONCLUSIONS: Our findings suggest that patients who at routine dental visits demonstrate evidence of bone loss around several teeth can predictably be identified as being at risk for future AMI. Such subjects should be referred for medical and periodontal examinations and treatments.