Human oral, gut, and plaque microbiota in patients with atherosclerosis.

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This study identified Chryseomonas in all atherosclerotic plaque samples, and Veillonella and Streptococcus species in the majority. The combined abundances of Veillonella and Streptococcus in atherosclerotic plaques correlated with their abundance in the oral cavity.

Gum disease has also been associated with atherosclerosis and P.Gingivalis antibodies (an oral pathogen) are also found in many  atherosclerotic plaques  Choi et al, 2011 
Gum disease, and atherosclerosis are also implicated in Alzheimer's disease