Risk Factors Of Short Root Anomaly In Maxillary Central Incisors

By integrating cone-beam computed tomography (CBCT), this study aims to characterize the features of short root anomaly (SRA) in maxillary central incisors and identify risk factors to inform clinical treatment. A retrospective study included 1472 orthodontic patients (558 males, 914 females) as research subjects who first visited the Orthodontics Department of Hospital between January 1st,2023, and October 31st,2023. Data collected included gender, age, Angle classification, oral habits, occlusal trauma, and labial frenum attachment. CBCT scans were analyzed using Dolphin software to assess root position relative to cortical plates, supernumerary teeth, ectopic teeth, and root-crown ratio (R/C, modified Lind method). Cephalometric radiographs were reconstructed for measurements. Patients were divided into normal and SRA groups. The proportion of maxillary central incisors with SRA among orthodontic patients and the risk factors for SRA occurrence in maxillary central incisors were statistically analyzed. SRA prevalence was 22.4%, with a mean R/C of 0.85±0.14. Significant differences (P<0.05) were found between two groups in skeletal classification, ANB angle, root position relative to cortical plates, ectopic teeth, mandibular plane angle, U1-L1 angle, OB, and OJ. Logistic regression identified the U1-L1 angle (OR 1.021, 95% CI 1.011–1.031) and the presence of ectopic teeth (OR 4.835, 95% CI 2.584–9.045) as independent SRA risk factors. SRA prevalence was 22.4%. An increased U1-L1 angle and the presence of ectopic teeth are key risk factors, warranting early clinical attention.