Is Apical Periodontitis a Contributive Risk Factor for Atherosclerosis?

Objectives: Atherosclerosis is a chronic inflammatory process, which leads to heart disease and death. Apical periodontists (AP) is a common inflammatory condition, associated with infected teeth. In a recent systematic review, we identified a positive association between AP and cardiovascular disease; however, no studies examined causality. We use a mouse model aiming to determine whether AP increases the risk for atherosclerosis. We hypothesize that atherosclerosis and systemic inflammation will be increased in mice with AP compared to mice without AP.
Methods: LDL-R-KO mice were used. AP was induced, by exposing the dental pulp of 4 molars in each mouse (group 1, n=14). Controls received only anesthesia (group 2, n=14). Next, all mice started high-fat diet to induce atherosclerosis. Measurements of plasma are taken to characterize the inflammatory profile (cytokine array) and oxidative stress (ELISA) at baseline, 8 weeks and 16 weeks after AP induction. At 16 weeks the mice are euthanized and the aortas are collected to measure the atherosclerosis lesion burden (stained with Oil red). AP lesions are validated and characterized by micro-CT and histology.
Results: The micro-CT scans of the jaws confirm successful establishment of AP lesions in the LDLR-KO mice. Mice in the AP group (n=13) as well in the control group (n=12) have successfully reached the endpoint of the study (16 weeks). These results demonstrate the feasibility of AP induction in LDLR-KO mice.
Conclusions: Our results may provide the first evidence for a causative relationship between AP and atherosclerosis. This model can be used in our next studies to probe in detail the mechanism. Since AP often goes unnoticed by patients and physicians, they would benefit from increased awareness about the potential impact of oral infections on total health and apply screening modalities (dental radiographs) and dental treatment for AP in patients with increased risk for cardiovascular diseases.