https://pubmed.ncbi.nlm.nih.gov/22390255

Findings: Five publications were included and reviewed. Two studies showed improved oral health care diminished risk of developing aspiration pneumonia and the risk of dying from aspiration pneumonia directly.  Three studies showed adequate oral health care decreased the amount of potential respiratory pathogens and suggested a reduction in the risk of aspiration pneumonia by improving swallowing reflex and cough reflex sensitivity.

This current systematic literature review defined oral health care: “toothbrushing after each meal, cleaning dentures daily and professional oral health care once a week”.