TABLE 3.
Spirochete counts by DF microscopy and identification of treponema species by nPCR in health-associated plaque from subjects with periodontitis (group HD)
| Individual plaque sample | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | No. of samples/species |
|---|---|---|---|---|---|---|---|---|---|---|---|
| DF resulta | 0 | 0 | 0 | 610 | 8 | 15 | 2,000 | 760 | 120 | 0 | |
| nPCR amplification result for spirochete | |||||||||||
| T. amylovorum | − | − | − | + | + | + | + | + | + | − | 6 |
| T. denticola | − | − | + | + | − | + | + | + | + | + | 7 |
| T. maltophilum | − | − | − | + | + | + | + | + | + | + | 7 |
| T. medium | − | − | + | + | + | + | + | + | + | − | 7 |
| T. pectinovorum | − | + | − | + | + | + | + | − | − | − | 5 |
| T. socranskii | + | + | − | + | + | + | + | + | + | + | 9 |
| T. vincentii | + | + | − | + | − | − | − | − | − | − | 3b |
| No. of species/sample | 2 | 3 | 2 | 7 | 5 | 6 | 6 | 5 | 5 | 3 |
a
Proportion of DF microscopy-positive samples was significantly less than proportion of PCR-positive samples (P = 0.043; Fisher exact probability test). Results are shown as 103 treponemas per sample. The mean count ± SD was (590 ± 760) × 103 treponemas (n = 6).
b
Proportion of HD subjects with T. vincentii was significantly less than that of DD subjects (Table 4).