Transient oral microflora in Greeks attending day centres for the elderly and residents in homes for the elderly

Objective: To examine the isolation frequency and the carriage of yeasts, Enterobacteriaceae, Staphylococcus and Enterococcus species in oral samples from elderly Greeks living alone or in institutions. Background: Ageing may promote changes in the oral ecosystem, which lead to colonisation of the mouth by microbes found less commonly or only transiently in younger subjects. Previous studies indicate a geographical variation in the isolation frequency of such bacteria in elderly populations. Materials and methods: Medical and dental records were obtained from 66 attenders at elderly people's day centres (EPDC), and 82 residents of elderly people's homes (EPH), 66–95 years old. Mucosa smear samples were cultured on appropriate media for enumeration of the above species. Microbial identification was performed by conventional microbiological tests. The results were analysed using the Multiple Correspondence Analysis (MCA), anova and other traditional statistical tests. Results: No statistically significant association was found between the place of residence and the wearing of dentures. The isolation frequencies of Staphylococcus aureus, Enterococcus and Enterobacteriaceae species were 21.6, 20.3 and 7.4% respectively. MCA, and further statistical analysis, revealed that the place of residence affected the isolation frequency of years (54.9% in EPH vs. 37.9% in EPDC). Moreover, anova showed that living in EPH increased the carriage of yeasts. Conclusions: Elderly Greeks exhibit a moderate to high oral carriage of transient bacteria compared with other elderly populations. Living in EPH seems to increase both the isolation frequency and carriage of yeasts.