Features of external root resorption as predictors of disease progression: A CBCT cross-sectional study

This cross-sectional study aimed to investigate predictive indicators in external cervical root resorption (ECR) through a quantitative and qualitative approach. Cone-beam computed tomography examinations of 92 teeth were analyzed qualitatively (sex, age, affected tooth, endodontic treatment, periapical status, and ECR: 3D classification, location of portal of entry, and presence of portal of exit); and quantitatively (lesion height, diameter of portal of entry, distance from the cement-enamel (CEJ) to bone crest and portal of entry, and ECR density). Descriptive statistics, chi-square tests, binomial logistic regression with odds ratio (OR), Spearman's correlation, Mann-Whitney U, and Kruskal-Wallis tests were performed, with a significance level of 5% (p < 0.05). Most lesions extended into the root`s mid-third. Circumferential spread was predominant > 270°, and most of them exhibited probable pulpal involvement. The mean lesion height was higher for anterior teeth (p = 0.032). The portal of entry was predominantly supracrestal and intraosseous. Distance from the portal of entry to the CEJ and the ECR height were inversely correlated (p < 0.001). The circumferential spread of "> 180° to ≤ 270°" demonstrated its predictive capability for the presence of a portal of exit (p = 0.028, Odds Ratio = 15). Lesions confined to dentin tended to be more hypodense, while those with probable pulp involvement were more hyperdense. ECR with a portal of entry farther from the CEJ showed less severe involvement. It was concluded that circumferential spread of "> 180° to ≤ 270°" could predict the presence of a portal of exit, and density pattern variations may provide valuable indicators for treatment planning and outcome prediction.