Bj. Moncla et al., DIRECT-DETECTION OF PORPHYROMONAS-GINGIVALIS IN MACACA-FASCICULARIS DENTAL PLAQUE SAMPLES USING AN OLIGONUCLEOTIDE PROBE, Journal of periodontology, 65(5), 1994, pp. 398-403
OLIGONUCLEOTIDE PROBES COMPLEMENTARY to the hypervariable regions of t
he 16S rRNA of Polphyromonas gingivalis, and previously shown to speci
fically identify human P. gingivalis strains to the species level, wer
e tested for their ability to recognize P gingivalis from nonhuman pri
mates (Macaca fascicularis), either as distinct isolates or in subging
ival dental plaque. The P-32-labeled probes hybridized with all 147 mo
nkey isolates identified as P. gingivalis by morphology and biochemist
ry, but did not hybridize with any of the 331 isolates representing 17
genera of bacteria unrelated to P gingivalis, or to the more closely
related P. endodontalis and P. asaccharolytica. This corresponds to se
nsitivities and specificities of 100%. Of 76 M. fascicularis plaque sa
mples, P gingivalis was detected by probe and culture in 67. Of 26 hum
an plaque samples taken from separate individuals free of periodontal
disease, 23 failed to demonstrate P. gingivalis by probe or culture. T
he results of the combined 102 monkey and human plaque samples indicat
e that, when compared to culture as the ''gold standard,'' the P gingi
valis probe had a sensitivity of 96%, a specificity of 87%, and an ove
rall agreement with culture of 93%. These results reveal that the olig
onucleotide probes used to identify P. gingivalis are specific for thi
s organism, and give results comparable to culture methods for detecti
ng the presence of P. gingivalis in M. fascicularis dental plaque.