Date of Award



Department of Orthodontics

First Advisor

Heesoo Oh

First Committee Member

James Chen


Introduction: The purpose of this study was to investigate variance in prevalence and severity of short root anomaly (SRA) in patients seeking orthodontic treatment, stratified by ethnicity and sex. Materials and Methods: In this retrospective cross-sectional study, we evaluated 896 patients who had initial cone-beam computed tomographies (CBCTs) taken from July 1, 2014 to May 30, 2019. Panoramic radiographs and images from the CBCTs of each patient were extracted and placed in a database. The crown-to-root ratio of maxillary central incisors, lateral incisors, canines, and all pre-molars were evaluated to determine the presence, severity and associations of SRA. A Chi-square test and ordered logistic regression were used. Results: SRA was seen in 10.04% of the sample (90 patients). The maxillary central incisors are the most frequently and bilaterally affected. The severity of SRA among those with SRA showed statistically significant differences between the ethnic groups. Associations been SRA and Hispanic patients were found to be significant when evaluated by ordered logistic regression (P<.0001, Odds ratio=7.54, 95% CI 3.08-18.48). Conclusions: The prevalence of SRA was highest in Asian and Hispanic patients. Hispanic patients were most affected by severe forms, while Asian patients were most affected by mild forms. In patients classified with SRA, Hispanic and Latino patients were found to have higher odds of getting SRA of the maxillary central and lateral incisors. In patients with moderate to severe SRA, there were greater odds of having SRA if a patient were Hispanic or Latino.