Oral Microbial Flora in Institutionalized Elderly People

Abstract

Dental examination and investigation of oral microbial flora in elderly people in two different institutions were performed and compared to each other in this study. Special attention was paid to the following : A) the number of Candida on the tongue and its correlation to denture wearing, and B) a comparison of Candida on the tongue of elderly people in both institutions versus that of elderly people living in their own homes* (*This study was a part of a project for the Ministry of Welfare investigating oral Candida in patients 70 and 80 years old). Subjects had been institutionalized in a nursing home in Kanagawa (n=50) and in a hospital for elderly people in Tokyo (n=29) and their mean age was 80.9 years old. Salivary flow rate, buffering capacity, the numbers of lactobacilli and mutans streptococci in saliva, and the numbers of Candida and staphylococci on the tongue were investigated after dental examinations were performed. When comparing the all results obtained from the nursing home and the hospital for elderly people, there were no differences. However, when comparing elderly people divided into denture-wearing and non-denture-wearing groups, the numbers of Candida and staphylococci on the tongues of those in the denture-wearing group were significantly higher than those of the non-denture-wearing group. The number of subjects who were classified in Grade IV (the number of Candida on the tongue was more than 101 CPU) was higher in the institutionalized elderly people than in the elderly people living in their own homes. These results suggested that the institutionalized elderly people had a higher number of Candida on the tongue, and denture wearing increased the number of Candida in the oral cavity because it acted as a reservoir for oral Candida.