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Updated: Jul 19, 2026

Oral Health Assessment by Lay Personnel for Older Adults
Published on: February 2, 2020
Cariogenic bacteria and caries risk in elderly Japanese aged 80 and older with at least 20 teeth
Omar M M Rodis1, Tsutomu Shimono, Seishi Matsumura
1Department of Behavioral Pediatric Dentistry, Hospital of Medicine and Dentistry, Okayama University, Okayama City, Japan. omarodis@md.okayama-u.ac.jp
Objectives:
To assess caries risk and check the presence of four commonly found oral cariogenic bacteria in "8020" achievers.
Design:
Initial report based on Japan's newly implemented "8020" campaign, which aims to promote health and awareness in older people. Simply stated, the goal is, at 80 years, to maintain 20 teeth.
Setting:
Healthy community-dwelling elderly individuals of Okayama Prefecture, Japan.
Participants:
One hundred sixty individuals aged 80 and older with 20 of their own natural teeth.
Measurements:
General and oral health conditions, caries risk assessment using the Cariostat method, and polymerase chain reaction (PCR) detection of four oral cariogenic bacteria.
Results:
The participants had an average of 24.7 teeth, of which 12.1 were sound, 12.2 were treated, and 0.4 were untreated. Based on Cariostat scores, 64.4% had low caries risk. Using PCR, Streptococcus mutans, S. sobrinus, Lactobacillus casei, and L. plantarum were detected in 51.3%, 23.1%, 40%, and 25% of the participants, respectively. S. mutans (P<.001), S. sobrinus (P=.002), L. casei (P<.001), and L. plantarum (P=.001) deoxyribonucleic acid band was detected more in participants with high caries risk scores.
Conclusion:
Participants with low caries risk scores had low prevalence of cariogenic bacteria, 20 or more sound teeth, and fewer missing teeth. Incorporating caries risk assessment, using the Cariostat and PCR analysis, in the "8020" campaign in health systems worldwide will contribute to a better life for the aging society, initiate research interest regarding the program, and improve current health policies.
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