Evaluation of the relationship between obturation length and presence of apical periodontitis by CBCT: an observational cross-sectional study

ObjectiveThe aim of this study was to evaluate the relationship between length of root canal obturation (RCO) and the presence of apical periodontitis (AP) in different dental groups using cone-beam computed tomography (CBCT) analysis.Materials and methodsA total of 392 roots with canal treatment performed for more than 4years were evaluated using CBCT. Distances from the apex to the tip of filling material were measured and classified as more than 2mm short of the apex, approximately 1-2mm short of the apex, at the apex, and beyond the apex. Odds ratio, confidence interval, and the (2) test were used for statistical analyses.ResultsThe frequency of AP was significantly greater in molars than in the other tooth groups (p<0.05). Moreover, RCO that ended 1-2mm short of the apex was associated with a lower prevalence of AP in molars and premolars (p<0.05) and in anterior teeth (p<0.1) when compared with RCO at the apex, more than 2mm short of the apex, or beyond the apex. When the RCO reached the apex, there was no difference in the presence of AP among dental groups (p>0.05).ConclusionThe length of RCOs can influence the presence of AP, with molars showing a higher prevalence. RCOs ending 1-2mm short of the apex are associated with an absence of AP.Clinical relevanceThe length of obturation is related to the presence of apical peridontitis and consequently to the success of endodontic treatment.