Molecular detection and identification of Synergistes phylotypes in primary endodontic infections

Aim: Uncultivated phylotypes from the Synergistes group have recently emerged as suspected endodontic pathogens. This study aimed to investigate the presence and identity of these bacteria in primary endodontic infections using a 16S rRNA gene-based group-specific hemi-nested polymerase chain reaction (PCR) protocol. Materials and methods: Genomic DNA was isolated directly from clinical samples and used as templates for PCR. Amplicons from positive specimens were sequenced and phylogenetically analyzed to determine species identity. Results: Overall, about one-third of the samples harbored Synergistes bacteria. The following phylotypes were disclosed: oral clones W028, BA121/P4G_18 P1, W090, BH017 and E3_33. Conclusions: These results demonstrated that as-yet uncultivated Synergistes phylotypes are present in the endodontic microbiota and a role in causation of apical periodontitis is suggested though remains unproven.