Purpose: A relationship between the distribution of periodontal bacteria species and malodor in children has not been sufficiently investigated. The present study was undertaken to determine the presence of 3 periodontopathic bacteria (Prevotella spp. P. intermedia, P. nigrescens, P. melaninogenica) in the supragingival plaques of 3 to 16-year-old children with different oral health conditions and oral malodor. Methods: The number of decayed and filled primary teeth (df) and Decayed, Missing and Filled permanent teeth (DMF),Papillary Marginal and Attached gingivitis (PMA) index, Oral Hygiene Index (OHI), and oral malodor of each subject were determined prior to the collection of supragingival plaques. Three periodontopathic bacteria(P. intermedia, P. nigrescens, P. melaninogenica ) in supragingival plaques were detected by using an immunoslot blot assay with monoclonal antibodies specific for each microorganism. Findings: The frequencies of periodontopathic bacteria in children with and without caries were not significantly different from each other. Positivity for P. intermedia, but not for P. nigrescens or P. melaninogenica was correlated with oral malodor. Oral malodor was also correlated with the debris index, a component of OHI.

The group with the higher OHI showed a higher prevalence of periodontopathic bacteria. For the 3 periodontopathic bacteria in the subjects tested, plaques positive for any of them were not age related. However,the frequencies of all 3 periodontopathic bacteria were the highest in the 3-6-year olds. Conclusion: The supragingival plaques in children can harbor 3 species of periodontopathic bacteria, P. intermedia,P. nigrescens, and P. melaninogenica.