Evaluation of alveolar bone morphology of incisors with different sagittal skeletal facial types by cone beam computed tomography: A retrospective study
Xu Zhang,
Jie Gao,
Weifu Sun,
Haolin Zhang,
Wen Qin,
Zuolin Jin
Affiliations
Xu Zhang
State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, China
Jie Gao
State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, China
Weifu Sun
State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, China
Haolin Zhang
State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, China
Wen Qin
State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, China
Zuolin Jin
Corresponding author. Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, No.145, Changle West Road, Xi'an, Shaanxi, China.; State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, China
Background: Safe orthodontic tooth movement should be performed within the alveolar bone. The purpose of this study was to evaluate the morphology of the alveolar bone of incisors. Materials and methods: This retrospective study included pretreatment cone beam computed tomography of 120 patients with malocclusion. Patients were divided into 4 groups (Class I, Class II division 1, Class II division 2 and Class III) according to the subspinale-nasion-supramental (ANB) angle and occlusal relationship. The sagittal root positions, anterior and posterior root-cortical bone angles (AR-CA and PR-CA), root-crown ratios (RCR) and alveolar bone thickness were evaluated. Results: The sagittal root positions were mainly positioned against the labial cortical plate in the maxillary incisors of the Class II division 2 group and engaged by both the labial and palatal cortical plates in the mandibular incisors of the Class III group. The AR-CA was lower than that in the other groups (P 0.05), the middle and lower anterior alveolar thickness (LAAT and MAAT) were lower than those in other groups (P < 0.01) in the maxillary incisors of the Class II division 2 group, and the alveolar thickness at the measurement sites of the middle and lower line were lower than those in other groups (P < 0.01) in the mandibular incisors of the Class III group. The RCR had a moderate positive correlation with the LAAT. Conclusion: Based on several limitations, this study found that maxillary incisor roots were at risk of penetrating the alveolar bone of Class II division 2 patients, and mandibular incisors may have a relatively small range of safe movement on both the labial and lingual sides of Class III patients during orthodontic treatment.
