摘要：Previous cultural microbiology and fluorescence labelling studies indicate an ecological basis for the relationship between Streptococcus mutans and human dental caries. The present study further investigated the basis of this postulated relationship by sampling gingival margin plaque at sites more or less stagnant and, therefore, more or less caries prone in relation to the contact area. Six hundred and thirty-two samples were obtained from 180 teeth in 74 children, comprising gingival margin approxinial plaque from embrasure (away), to the side of, over and below the contact area. These were processed by indirect inimunofluorescence using an S. mutans polyclonal antiserum. While S. mutans was not detectable in many sites, in spite of high sensitivity and specificity of the antiserum, there was a significant tendency (P < 0.05) for the proportional direct (labelled) microscopic count to increase apical to the contact area.Keywords: Streptococcus mutans; Caries; Ecology.
