Factors associated with CBCT-detected periapical radiolucencies in root-filled teeth: a retrospective cross-sectional...

This retrospective cross-sectional study assessed the prevalence of cone-beam computed tomography (CBCT)-detected periapical radiolucencies and their associations with demographic, anatomical, and treatment-related factors in root canal-treated teeth. CBCT scans from 390 patients (226 females and 164 males; mean age, 45.87 ± 14.96 years) comprising 994 root-filled teeth were examined. Periapical status was assessed using the CBCT periapical index (CBCT-PAI), with CBCT-PAI ≥ 3 defined as the primary outcome. Obturation length and density, procedural errors, tooth location, and patient-level characteristics were evaluated. Adjusted associations were estimated using binary logistic generalized estimating equations accounting for clustering of teeth within patients. CBCT-PAI ≥ 3 was identified in 235 teeth (23.6%). Missed canals (adjusted odds ratio [aOR], 3.70; 95% confidence interval [CI], 2.06-6.65), overextended fillings (aOR, 4.16; 95% CI, 2.02-8.54), and short fillings (aOR, 2.74; 95% CI, 1.89-3.97) were independently associated with higher odds of CBCT-PAI ≥ 3 (all p < 0.001). Increasing age (aOR per year, 0.980; 95% CI, 0.966-0.995; p = 0.009) and mandibular location (aOR, 0.64; 95% CI, 0.45-0.92; p = 0.016) were associated with lower odds. Sensitivity analyses using alternative CBCT-PAI thresholds supported the associations of missed canals and non-ideal obturation length. Missed canals and short or overextended fillings were the most consistent radiographic correlates of periapical radiolucencies; however, the cross-sectional design precludes causal or prognostic conclusions.