TABLE 2.
Distribution of oral microbial samples positive for monomicrobial and polymicrobial infections as determined by PCR
| Bacterial infection | Total no. of rats | No. of oral microbial samples positive fora:
|
|||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
P. gingivalis
|
T. denticola
|
T. forsythia
|
F. nucleatum
|
||||||||||||||||||
| 1 wk | 2 wk | 3 wk | 4 wk | 1 wk | 2 wk | 3 wk | 4 wk | 5 wk | 6 wk | 1 wk | 2 wk | 3 wk | 4 wk | 5 wk | 6 wk | 1 wk | 2 wk | 3 wk | 4 wk | ||
| Monomicrobial infectionsb | |||||||||||||||||||||
| P. ginigvalis 381 | 8c | 7 | 7 | 7 | 3 | ||||||||||||||||
| T. denticola ATCC 35404 | 5 | −d | − | − | 4 | 5 | 4 | ||||||||||||||
| T. forsythia ATCC 49307 | 5c | 1 | − | 1 | 3 | 4 | 4 | ||||||||||||||
| Control uninfected rats | 10 | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − |
| Polymicrobial infections | |||||||||||||||||||||
| Expt I (P. ginigvalis + T. denticola + T. forsythia) | 10 | 10 | 6 | 7 | 9 | 10 | 5 | 7 | 8 | 10 | 5 | 8 | 10 | ||||||||
| Expt I (P. ginigvalis + T. denticola + T. forsythia + F. nucleatum) | 11 | 9 | 6 | 7 | 7 | 8 | 5 | 7 | 7 | 6 | 4 | 7 | 8 | 11 | 11 | 7 | 10 | ||||
| Expt II (P. ginigvalis + T. denticola + T. forsythia) | 11 | 10 | 4 | 9 | 11 | 1 | − | − | 11 | 9 | 5 | 10 | 9 | ||||||||
| Control uninfected rats | 8 | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | − | ||||
Total numbers of oral microbial samples that were collected in subsequent weeks (1, 3, 5, 7, 9, and 11 weeks [Fig. 1]) following monomicrobial or polymicrobial infection and were positive as determined by PCR analysis. Control uninfected rat microbial samples were collected periodically and examined for P. gingivalis, T. denticola, T. forsythia, and F. nucleatum using bacterium-specific primers, and all rats were negative for all the species.
Rats were infected for 4 weeks (P. gingivalis) or 6 weeks (T. denticola and T. forsythia) alternatively, and oral microbial samples were collected in the following weeks and analyzed using appropriate bacterium-specific PCR primers along with positive and negative controls.
One rat in each group infected with P. gingivalis or T. forsythia was removed before the end of the experiment due to tumor growth in the neck region.
−, oral microbial samples were negative as determined by PCR analysis.