Abstract:

Objective　To observe the prevalence ofPorphyromonas gingivalis(Pg),Treponema denticola(Td) andBac- teridesforsythus(Bf) subgingivally in diseased sites of chronic periodontitis (CP) patients.Methods　Samples of subgingival plaque were detected by 3 kinds of oligonucleotide DNA probe from 60 sites of CP patients and 10 healthy sites of 10 healthy peo- ple.Results　The positive rates ofPg,BfandTdin patients were 91·67%, 90·00% and 95·67% respectively;Pg,Bfand Tdwere detected simultaneously in 83·33% patients andPg,BfandTdwere found to be related with each other(P<0·01). Conclusion　Pg,BfandTdwere prominent periodontopathic bacteria and related each other, might exist in complexes in sub- gingival plaque and coaggretate together.

Key words: periodontitis, Porphyromonas gingivalis, Treponema denticola, Bacteridesforsythus, oligonucleotide DNA probe