title: [The role of CBCT in evaluation of alveolar bone state during orthodontic-periodontal treatment].
abstract: OBJECTIVE
  To evaluate the role of cone beam computed tomography (CBCT) in evaluation of alveolar bone state during orthodontic-periodontal treatment.
  
  
  METHODS
  Twenty patients with periodontal disease seeking for orthodontic-periodontal therapy were selected. The first stage of orthodontics included alignment and leveling arches (treatment) and the average period was 6 months. CBCT for anterior teeth was taken before and after treatment, and alveolar bone density and height were recorded with landmark identification designed by ourselves in this study. The data was analyzed with SPSS16.0 software package for paired t test and interclass correlations (ICC) assessments.
  
  
  RESULTS
  Paired t test showed that the alveolar density was significantly reduced after treatment (P=0.02) and no significant change of alveolar height was observed before and after treatment (P=0.74). The value of ICC was more than 0.9 for all intra-observer and inter-observer assessments.
  
  
  CONCLUSIONS
  The alveolar bone density decreased during orthodontic treatment and CBCT could be used in evaluation of alveolar bone state. The landmark identification designed by ourselves can offer consistent and reproducible data. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality(Grant No.08DZ2271100). Dr.MA ZG and FAN LF Contributed equally to the study.
authors.affiliation: Department of Oral and Maxillofacial Surgery, College of Stomatology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China. braces_dr@hotmail.com
authors.forename: Zhi-gui
authors.initials: ZG
authors.lastname: Ma
authors.forename: Lin-feng
authors.initials: LF
authors.lastname: Fan
authors.forename: Bing
authors.initials: B
authors.lastname: Fang
mesh_terms: D000539:Alveolar Process; D015519:Bone Density; D002681:China; D054893:Cone-Beam Computed Tomography; D006801:Humans; D009970:Orthodontics; D010517:Periodontics