Correlation between microbial host factors and caries among older adults

Area of Science:

• Oral Health Research
• Microbiology
• Gerontology

Background:

• Limited understanding of factors influencing oral health in older adults.
• Focus on the relationship between specific bacteria and caries in this demographic.

Purpose of the Study:

• To determine the association between Streptococcus mutans (MS) and Lactobacilli (LB) bacterial counts and dental caries experience in adults aged 60 and above.
• Investigate the role of salivary factors (flow rate, buffering capacity) in this relationship.

Main Methods:

• Community-based observational study in Singapore involving 141 participants aged 60+.
• Saliva samples collected for bacterial counts (MS, LB), salivary flow rate, and buffering capacity assessment.
• Clinical examination to record caries experience (DMFT index).

Main Results:

• High counts of MS (≥10^5) found in 67.4% and LB (≥10^5) in 48.2% of participants.
• Multivariate analysis indicated high MS counts were associated with lower DMFT (<12) and high LB counts with lower DMFT (≤14).
• Alkaline saliva buffering capacity observed in 61% of participants.

Conclusions:

• A positive correlation exists between MS and LB counts and caries experience in older adults.
• The relatively low mean DMFT despite high bacterial counts suggests other host and environmental factors are significant.
• Dental caries etiology in older adults is complex and age-group specific.