Investigation of six selected bacterial species in endo-periodontal lesions

To investigate and determine possible associations of six tested bacteria belonging to 'orange' and 'green' complexes, in endo-periodontal lesions: Parvimonas micra, Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens and Capnocytophaga sputigena.

Forty-six patients presenting with different types of endo-periodontal lesions were investigated. Clinical examinations, periapical radiographs and microbiological sampling from the canal system (endo) and periodontal pockets (perio) were performed. Qualitative and semiquantitative evaluation of bacteria was performed by polymerase chain reaction (PCR) and DNA-DNA hybridization (micro-IDent plus; Hain Lifescience, Germany).

Extremely high bacterial loads in endodontic samples were recorded for P. micra, F. nucleatum and C. sputigena, while periodontal samples were often colonized by the same species, plus C. rectus. Significant association was recorded between F. nucleatum-endo and P. micra-endo (P = 0.03, Fisher's exact test). There was marginal evidence of associations between: (i) C. sputigena-endo and C. sputigena-perio (P = 0.06, Fisher's exact test); (ii) P. micra-endo and P. micra-perio (P = 0.05, Fisher's exact test). Sensitivity to percussion was associated with an increased chance of cases with P. micra-endo (P = 0.03, Pearson chi-square test).

The findings suggest that F. nucleatum, P. micra and C. sputigena may play a role in the pathogenesis of endo-periodontal lesions.