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Updated: Feb 13, 2026

The Use of Chemostats in Microbial Systems Biology
Published on: October 14, 2013
Salivary microbial profiles in relation to age, periodontal, and systemic diseases
Ronaldo Lira-Junior1,2, Sigvard Åkerman3, Björn Klinge1,4
1Karolinska Institutet, Department of Dental Medicine, Division of Oral Diseases, Stockholm, Sweden.
Background:
Analysis of saliva is emerging as a promising tool to diagnose and monitor diseases which makes determination of the salivary microbial profile in different scenarios essential.
Objective:
To evaluate the effects of age, periodontal disease, sex, smoking, and medical conditions on the salivary microbial profile.
Design:
A randomly selected sample of 441 individuals was enrolled (51% women; mean age 48.5±16.8). Participants answered a health questionnaire and underwent an oral examination. Stimulated saliva was collected and the counts of 41 bacteria were determined by checkerboard DNA-DNA hybridization.
Results:
Elderly participants (> 64 years old) presented a significant increase in 24 out of 41 bacterial species compared to adults (≤ 64 years old). Eubacterium nodatum, Porphyromonas gingivalis, and Tannerella forsythia were significantly higher in participants with generalized bone loss compared to without. Males and non-smokers had higher bacteria counts in saliva. Individuals having mental disorders or muscle and joint diseases showed significantly altered microbial profiles whereas small or no differences were found for subjects with high blood pressure, heart disease, previous heart surgery, bowel disease, tumors, or diabetes.
Conclusion:
Age, periodontal status, sex, smoking, and certain medical conditions namely, mental disorders and muscle and joint diseases, might affect the microbial profile in saliva.
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