Quantitative Analysis of Candidate Endodontic Pathogens and Their Association with Cause and Symptoms of Apical Periodontitis in a Sudanese Population

Objective:To investigate the prevalence of key endodontic pathogens and their association with the clinical features and the cause of apical periodontitis.Methods:The study population included patients referred to Khartoum Dental teaching Hospital, Sudan for endodontic treatment. Samples were collected from single-rooted teeth carious or traumatised teeth with clinical and radiographic evidence of apical periodontitis. The endodontic pathogens Porphyromonas endodontalis, Fusobacterium nucleatum and Treponema denticola were quantified by real time polymerase chain reaction (qPCR). The prevalence of each species was identified at both a low detection threshold (>50bacteria) and a high detection threshold (>1000 bacteria).Results: 75 patients (mean age 30.1 yrs SD 10.1) were included in the analysis. The most prevalent bacterium at both the low and high threshold was F. nucleatum followed by T. denticola at the low threshold and P. endodontalis at the high threshold. There was no association with symptoms at the low detection threshold, but at high threshold P. endodontalis was associated with swelling, adjusted odds ratio (OR),9.32 95%CI 1.11- 78.66, P=0.04. All species were more prevalent in apical periodontitis due to caries only at the low detection threshold, OR=5.01 (P=0.006) for T. denticola; 4.84 (P=0.01) for F. nucleatum; and 3.62 (P=0.03) for P. endodontalis.Conclusion: There was a high prevalence of the F. nucleatum, T. denticola and P. endodontalis in apical periodontitis associated with caries. None of these bacterial were associated with pain but the presence of P. endodontalis at high levels was associated with swelling.