Aim of the study was to assess dental caries using Modified Dentition Status and Treatment Needs and find its association with salivary Streptococcus mutans and lactobacilli counts among 12-year-old school children of Belgaum city.

A self-designed, 13 item, open-ended questionnaire given to parents. Children were examined for dental caries using Modified Dentition Status and Treatment Needs. Stimulated saliva was collected and incubated to estimate lactobacilli and Streptococcus mutans colonies. Chi-square test was used to find the association between variables.

When DMFT was recorded it was found that 23% of children were free from dental caries, whereas, only 5% of them were free of dental caries when examined using modified criteria. Most of the children had higher microbial count with 72% and 62% of them having > 10⁵ cfu/μl of Streptococcus mutans and lactobacilli colony count respectively. Modified DMFT was significantly associated with frequency of brushing, lactobacilli and Streptococcus mutans counts (p < 0.05).

The proportion of subjects with dental caries was relatively high in all groups but the number of teeth affected by caries was low. Inclusion of noncavitated incipient lesions could increase sensitivity of index.