The detection of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia using an ELISA in an adolescent population with early periodontitis

The aim of the study was to compare the occurrence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia in the subgingival plaque from sites with and without early periodontitis in adolescents using an ELISA. 47, 15- to 16-year-old adolescents (39 Indo-Pakistani, 8 white Caucasian) were examined for clinical attachment level, probing depth, supragingival plaque, subgingival calculus and bleeding on probing on the mesio-buccal and disto-buccal aspects of the Ist molars and the incisors. Based on the clinical data. 2 sites per subject were selected for subgingival plaque sampling 3 weeks later: in 32 subjects with loss of attachment greater than or equal to 1 mm, a diseased site (D) and a healthy comparison control site (C) were sampled, in 15 subjects in whom loss of attachment had not yet developed, 1 of the upper molar sites was selected, called the at-risk site (R), together with a C site. The presence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia were determined using an ELISA. The loss of attachment subgroup had significantly more pockets greater than or equal to 4 mm, subgingival calculus and bleeding on probing (p<0.05). Significantly more of the D than C sites had P. gingivalis both at detectable and at measurable levels (p<0.05). In subjects who had no loss in clinical attachment levels, fewer sampled sites harboured any of the suspected periodontopathogens investigated, and no significant differences were found between the R or C sites (p>0.05). Although there was a significantly higher prevalence and extent of loss of attachment greater than or equal to 1 mm in the Indo-Pakistani subjects compared with the Caucasians (p<0.05), no differences could be identified in the distribution of the bacteria. It is concluded that monitoring of the subgingival plaque may be useful in studies of early periodontitis in adolescents, and the role of P. gingivalis needs to be elucidated in prospective longitudinal investigations.