| Ranking | Bacteria species | Fisher’s exact test | Hierarchy |
| (p-value) | |||
| 1 | Fretibacterium fastidiosum | 0.0001 | Hierarchy I (p < 0.01) |
| 2 | Corynebacterium durum | 0.0002 | |
| 3 | Slackia exigua | 0.0004 | |
| 4 | Tannerella forsythia | 0.003 | Hierarchy II (p < 0.05) |
| 5 | Eubacterium nodatum | 0.005 | |
| 6 | Porphyromonas endodontalis | 0.015 | |
| 7 | Filifactor alocis | 0.015 | |
| 8 | Eubacterium yurii | 0.024 | |
| 9 | Eubacterium infirmum | 0.024 | |
| 10 | Campylobactor rectus | 0.037 | |
| 11 | Treponema denticola | 0.054 | Hierarchy III (p > 0.05) |
| 12 | Porphyromonas asaccharolyticus | 0.112 | |
| 13 | Eubacterium saphenum | 0.112 | |
| 14 | Porphyromonas gingivalis | 0.158 | |
| 15 | Prevotella nigrescens | 0.181 | |
| 16 | Porphyromonas uenonis | 0.273 | |
| 17 | Prevotella melaninogenica | 0.472 | |
| 18 | Prevotella intermedia | 0.472 | |
| 19 | Solobacterium moorei | 0.472 | |
| 20 | Corynebacterium matruchotii | 0.472 |