Associations Among Tooth Loss, Periodontitis, and Carotid Intima-Media Thickness: the Nagahama Study

Aims: This study aimed to clarify the relationships among tooth loss, periodontal condition, and subclinical atherosclerosis from the aspect of intensity, extent, and duration of inflammation. Methods: This cross-sectional study included 9,778 people from the Nagahama Study, a large-scale, general population-based study conducted in Japan. The number of teeth and periodontal status, including the attachment level (AL) and pocket depth (PD) of representative teeth from six regions, were evaluated by dentists. The maximum intima-media thickness (IMT) of the common carotid artery was used as an index of atherosclerosis.Results: In the multivariate analysis adjusted for conventional risk factors, a large number of missing teeth (＜9 remaining teeth), which related to long-lasting inflammation indicative of the highest stage of periodontitis, was identified as an independent determinant of IMT in a general population (coefficient: 0.042; 95% confidence interval [CI]: 0.016 to 0.068). The presence of two or more regions with an AL ≥4 mm, which is indicative of the progressing, long-lasting stages of periodontal inflammation, was also independently associated with IMT (coefficient: 0.016; 95% CI: 0.004 to 0.028). On the contrary, PD, a measure of the early and reversible phases of periodontal inflammation, and loss of AL in the group without tooth loss were not significantly associated with IMT, because of the limited degree of accumulated periodontitis.Conclusion: The present results suggest that the association between periodontitis and atherosclerosis depends on the inflammation intensity, extent, and duration.