Detection of Slackia exigua, Mogibacterium timidum and Eubacterium saphenum from pulpal and periradicular samples using the Polymerase Chain Reaction (PCR) method

Aim The purpose of this study was to detect Slackia exigua from root canal samples using a sensitive PCR amplification method. Mogibacterium timidum and Eubacterium saphenum were also included because of their culture‐difficult properties. Methodology The species‐specific PCR primers were prepared according to 16S rDNA sequence analysis data, and confirmed to be effective for PCR amplification as species‐specific, respectively. A total of 36 clinical samples were obtained during the first visit of root canal treatment. Results The sensitivity of detection was a minimum of 10 organisms for S. exigua and five organisms for M. timidum and E. saphenum, respectively. In seven cases of pulpitis, S exigua was detected in two cases (29%), and M. timidum in two cases (29%), but E. saphenum was not detected. In 17 cases of root canal treatment, S.exigua was detected in seven cases (41%), M. timidum in 12 cases (71%) and E. saphenum in four cases (24%). In 12 cases of root canal retreatment, S. exigua was detected in three cases (25%), M. timidum in three cases (25%) and E. saphenum in two cases (17%). Conclusions S. exigua, M. timidum and E. saphenum were present in root canal systems, and may be associated with pulpal and periradicular pathosis.