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Updated: May 20, 2026
Three-Dimensional Cephalometric Landmark Annotation Demonstration on Human Cone Beam Computed Tomography Scans
Published on: September 8, 2023
Crown-root morphology of lower incisors in patients with class III malocclusion
Bo Wang1, Guofang Shen, Bing Fang
1Center of Cranio-facial Orthodontics, College of Stomatology, Affiliated 9th People's Hospital, Shanghai Key Laboratory of Stomatology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
Objective:
The purpose of this study was to investigate the crown-root morphology of lower incisors in patients with class III malocclusion using cone-beam computed tomography.
Methods:
Cone-beam computed tomography images were analyzed from 53 adult class I patients (group 1), 37 preadolescent class III patients (group 2), and 66 adult class III patients (group 3) comprising 3 divisions (divisions 1, 2, and 3 corresponded to mild, moderate, and severe class III malocclusions). The size and crown-root angulations of lower incisors in different groups and divisions were statistically appraised with group 1 used as the control group.
Results:
No significant differences were found for the size of lower incisors among different groups and divisions (P > 0.05). Compared with group 1, the crown-root angulations of lower incisors in groups 2 and 3 were significantly larger (P < 0.01), and among 3 divisions, the lower incisors of division 3 rather than divisions 2 and 3 exhibited larger crown-root angulations (P < 0.01).
Conclusions:
Attention should be paid to the enlarged crown-root angulations of lower incisors in class III patients during orthodontic and orthognathic treatment, especially in severe ones.
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