Detection of Treponema denticola in endodontic infections by 16S rRNA gene-directed polymerase chain reaction

A 16S rDNA-based polymerase chain reaction (PCR) method was used to detect the occurrence of Treponema denticola in root canal infections. Samples wer e collected from 21 single-root teeth having carious lesions, necrotic pulp s and radiographic evidences of periradicular bone loss. DNA extracted from the samples was amplified using the PCR assay, which yielded specific frag ment of T. denticola 16S rDNA. T. denticola was detected in 11 of 21 cases (52.4%), regardless of the presence or absence of symptoms. Since this spir ochete was found in a relatively high percentage of the endodontic infectio ns examined and because it is a pathogenic microorganism involved in period ontal diseases, there are reasons to believe that T. denticola can also par ticipate in the pathogenesis of periradicular lesions of endodontic origin.