Inﬂuence of infection at the time of root ﬁlling on the outcome of endodontic treatment of teeth with apical periodontitis U. S J Ö G R E N a , D. F I G D O R b , S . P E R S S O N a & G . S U N D Q V I S T a aFaculty of Odontology, Umeå University, Sweden, and bMelbourne, Australia
This study investigated the role of infection on the prognosis of endodontic therapy by following-up teeth that had had their canals cleaned and obturated during a single appointment. The root canals of 55 singlerooted teeth with apical periodontitis were thoroughly instrumented and irrigated with sodium hypochlorite solution. Using advanced anaerobic bacteriological techniques, post-instrumentation samples were taken and the teeth were then root-ﬁlled during the same appointment. All teeth were initially infected; after instrumentation low numbers of bacteria were detected in 22 of 55 root canals. Periapical healing was followedup for 5 years. Complete periapical healing occurred in 94% of cases that yielded a negative culture. Where the samples were positive prior to root ﬁlling, the success rate of treatment was just 68% – a statistically signiﬁcant difference. Further investigation of three failures revealed the presence of Actinomyces species in each case; no other speciﬁc bacteria were implicated in failure cases. These ﬁndings emphasize the importance of completely eliminating bacteria from the root canal system before obturation. This objective cannot be reliably achieved in a one-visit treatment because it is not possible to eradicate all infection from the root canal without the support of an inter-appointment antimicrobial dressing. Keywords: bacteria, one visit treatment, prognosis, root ﬁlling, success rate.
Because bacteria are critical for the development of apical periodontitis (Kakehashi et al. 1965, Sundqvist 1976, Möller et al. 1981) modern endodontic treatment is directed at the...