Article in Science Daily on a study of Alzheimer patients finds that gingivitis bacteria cause and aggravate Alzheimers dementia. Brush those teeth and floss regularly to keep both your teeth and your brain. https://www.sciencedaily.com/releases/2019/06/190603102549.htm
I heard the same about heart disease. a year or two back. https://www.bbc.com/news/10176410 (2010) and https://www.express.co.uk/life-style/health/1047823/heart-attack-symptoms-disease-signs-brush-teeth (2018 but no real references I can see -is that paper crap? )