Treponema species detected in infected root canals and acute apical abscess exudates.

Introduction: Different microbial communities have been associated with acute endodontic infections. The majority of the microorganisms are as yet uncultivable or difficult to grow under current laboratory conditions. Treponema species are strict anaerobic bacteria that are involved in several oral diseases. The aim of this study was to detect the presence of Treponema species in infected root canals (RCs) and exudates related to acute apical abscesses (AAAs) as well as to determine positive association between targeted species and clinical signs/symptoms.

Methods: Paired samples of infected RCs and AAAs were collected from 20 subjects. Nested polymerase chain reaction assay with species-specific primers for 16S rDNA and downstream intergenic spacer region was used for microbial detection. The frequency of species and statistical associations between species and signs/symptoms of endodontic origin as well as their simultaneous detection in both milieus were investigated.

Results: The most frequently detected species were T. socranskii (RC, 17/20; AAA, 15/20), T. denticola (RC, 8/20; AAA, 11/20); T. medium (RC, 6/20; AAA, 9/20); and T. amylovorum (RC, 5/20; AAA, 9/20). Positive correlation was found for simultaneous presence of T. denticola in both RCs and AAAs (p = 0.01). Positive association was observed between T. medium and T. vincentii (p = .037). No positive statistical association was observed between the targeted species and signs/symptoms.

Conclusions: The high incidence of Treponema species in RC and AAA samples from the same tooth indicated that they are important pathogens in acute endodontic infections.