Effect of oral care intervention on type and load of oral microorganisms associated with aspiration pneumonia and ill health in people with and without dementia living in residential aged care

Oral swabs from the cheek, gum, and tongue of a cohort of 27 people with dementia in residential aged care were analysed prior to and following a 6-week period of intervention. There was no significant difference in the abundance of bacteria and fungi at the three sites prior to intervention. There was a significant difference in the diversity of bacteria, compared to fungi, particularly for the tongue prior to intervention. Participants then self-selected into two groups, Control (n = 10; regular oral care) and Experimental (n = 17; evidence-based oral care [2-minutes of teeth brushing after meals twice per day or daily cleaning of dentures]) for the intervention period. Following intervention, participants receiving evidence-based oral care had significant decreases in four potentially pathogenic bacteria and an increased abundance of Lactobacillus reuteri, a protective bacteria, compared to participants receiving regular oral care. There were no significant differences between the groups for the abundance and type of fungi. The 6 weeks of evidence-based oral care also significantly reduced the absolute count of E. coli, a gut-based pathogen specifically associated with aspiration pneumonia. Although there are limitations with this study, results support the importance of evidence-based oral care for people with dementia, particularly those who are dependent on others for their oral care. Results also support the use of next-generation sequencing and analysis.