Prevalence of suspected periodontal pathogens identified using ELISA in adolescents of differing ethnic origins

The aim of this study was to determine the prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia in a group of adolescents and investigate the association of these organisms with various clinical parameters. A total of 527, 11-13-year-old children, of whom 333 (63%) were white Caucasian, 187 (35%) Indo-Pakistani and 7 (1%) Afro-Caribbean, participated in the study. Subgingival plaque samples, collected from the mesio-buccal of both upper first permanent molars using sterile paper points, were stored in phosphate buffered saline with 0.01% thiomersal and analysed for the presence of A. actinomycetemcomitans, P. gingivalis and P. intermedia using ELISA. The mesio-buccal sites of both upper 1st permanent molars were also examined and the presence/absence of supragingival plaque, subgingival calculus, bleeding on probing and pocket depths greater than 3 mm were recorded. The % of white Caucasian children in whom the monoclonal antibody identified at least 1 site with A. actinomycetemcomitans, P. gingivalis and P. intermedia were 4%, 3% and 2%, respectively, and for Indo-Pakistanis were 3%, 17% and 2%. The difference for P. gingivalis was statistically significant (p < 0.001). The associations between the clinical parameters and the 3 organisms were considered separately for both upper first molar sites. The prevalence of P. gingivalis was higher for sites with subgingival calculus, pockets > 3 mm and bleeding on probing (p < 0.01).