Well, a host of diseases whose underlying connection is that all are related to inflammation: heart and arterial disease, diabetes, Alzheimer's, Parkinson's.

https://www.bbc.com/future/article/20220707-why-bad-teeth-are-harmful-to-your-health

I'd heard bit of this before, but didn't realize the breadth of effects or the quality of the evidence (it has always come up as things that dental hygienists throw out).

>this before

Yeah, the theory is that bacteria is penentrating the brain blood barrier.  They found it while researching Alzheimer's.

"earlier research indicating that high cholesterol can increase permeability of the blood brain barrier"

Discovery of genetic connection between Alzheimer's and gut disorders
https://newatlas.com/medical/alzheimers-discovery-genetic-connection-gut-disorders/


Relation between periodontitis and helicobacter pylori infection - NIH.gov
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4659103/

"H. pylori can be detected in the periodontal pockets of patients with these gastric diseases and therefore is considered as the risk factor of periodontitis."

>>Alzheimer's and gut disorders

Anecdotally, that association seems true in my family.

Gum disease bacterium linked to breast cancer growth and spread
https://www.sciencedaily.com/releases/2026/03/260319044719.htm

I've mentioned in another thread that the TAVR surgeon wasn't worried about a serious, nasty UTI (Klebsiella) but wanted to have a discussion with my dentist. Reason: there's a dental bacteria that loves to attack the heart after procedures.