LAUSR

Background This study aimed to assess the prevalence of apical periodontitis (AP) and its association with the presence/quality of root canal filling (RCF) and coronal restoration (CR) in Iraqi population. Material and Methods A total of 385 CBCT scans of patients (18-45) yrs. old with 9250 teeth were examined. The teeth were grouped according to the presence/absence of apical radiolucency, presence/radiographic quality of RCF, and CR. Chi-square and Kappa were used to assess associations and intra-consensus reliability. Logistic regression was used to predict risk factors associated with AP. The significant level was set at p<0.05. Results AP was prevalent in 17.7 and 80.2% of teeth without RCT and with RCT (p<0.05), respectively. AP in root canal-treated teeth with missed canals (93.2%) was higher than that in root canal-treated teeth with no missing canal (78.3%) (p<0.05). AP in teeth with inadequate RCF (87%) was higher than that in teeth with adequate RCF (63%) (P<0.05). No difference in the prevalence of AP in teeth with adequate vs inadequate CR ((79.7%) vs (81%), respectively) (p>0.05). The presence of AP was significantly associated with inadequate RCF (vs adequate RCF) (OR=4.16, CI 95% 2.29-7.56, P<0.05), and was not associated with inadequate CR (vs adequate CR) (OR=-0.71, CI 95% 0.35-1.42, P>0.05). Intra-consensus reliability was (0.9) for AP and (0.82) for RCF and CR quality. Conclusions AP was highly prevalent in teeth with previous root canal filling compared to non-treated teeth. AP was significantly associated with inadequacy of root canal filling but not with the inadequacy of coronal restoration. Key words:Apical periodontitis, cone beam computed tomography, root canal treatment, endodontics.