Identification of etiological agents with molecular and convantional methods in patients with endodontic infections

The aim of this study is to investigate the presence of some selected anaerobic bacteria from the root canal samples of teeth with necrotic pulps and with failing endodontic treatment by using PCR method and determine the associations between pathogens and clinical symptoms.A total of 107 patients who applied to Cukurova University, Faculty of Dentistry, Department of Endodontics and have root canal treatment indication, were involved in this study. Root canal samples of 72 teeth with primary infection (necrotic pulp) with no prior endodontic treatment and 35 teeth with secondary infection (have apical periodontitis and prior root canal treatment) showing apical periodontitis symptoms were investigated in this study.The identification of selected anaerobic bacteria species: Fusobacterium nucleatum, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella melaninogenica, Prevotella nigrescens, Tannerelle forsythia, Peptostreptococcus micros in clinical samples of root canals of teeth with primary and secondary infections were done by in house PCR method by using spesific primers.Evaluation of positive samples in 107 of whole study samples showed the highest ratio of P.gingivalis which is positive in 55(51,4%) of 107 samples. This is followed by the positivity ratios of P.micros with 46,7% P.endodontalis with 44,9%, F.nucleatum with 43,9%, P.intermedia with 33,6%, T.forsythia with 30,8%, P.melaninogenica with 22,4% and P.nigrescens with 15,9% respectively.Evaluation of positive samples in teeth with primary and secondary infections showed rates of P.gingivalis were found to be 54,2% and 45,7% respectively in these groups and retained that it has the highest positivity in all of the anaerob species.When the positivity rates of all root canal samples evaluated it is found that 22,4% of samples showed only one genus positivity while 23,4% have only two genus positivity, 13.1% have three genus positivity, 27,1% have four genus positivity, 11,2% have five genus positivity and 2,8% have six genus positivity.F.nucleatum and P.gingivalis in teeth with primer infections were identified with ratios of 6,9% and 4.2% respectively and P.endotontalis and P.gingivalis in teeth with seconder infections identified with ratios of 14.3% and 8.6% respestivels in a simgle canal sample.Twenty one of 107 patients that root canal samples were taken, showed no clinical signs and symptoms were asemptomatic cases and 86 were found to be symptomatic cases who showed clinical signs and symptoms.Key words: Anaerobic bacteria, Endodontic, Primary infection, Secondary infection, Semptom