title: Cone beam computed tomography evaluation of distance from cementoenamel junction to alveolar crest before and after nonextraction orthodontic treatment.
abstract: OBJECTIVE
  To evaluate the distance between the cementoenamel junction and the alveolar bone crest before and after orthodontic treatment using cone beam computed tomography (CBCT).
  
  
  METHODS
  The sample comprised 30 patients with Angle Class I malocclusion and mild to moderate crowding. The study database comprised dental CBCT scans obtained before and after orthodontic treatment. The distance between the cementoenamel junction to the bone crest of the buccal (n  =  720) and lingual (n  =  720) surfaces was measured in 24 teeth for each patient using a specific software tool (Xoran version 3.1.62). The Wilcoxon test was used for statistical analysis, and the level of significance was set at P < .05.
  
  
  RESULTS
  The distance between the cementoenamel junction and the bone crest increased in 822 (57%) of the 1440 surfaces after orthodontic treatment. The buccal surface of the lower central incisors had the greatest frequency of increased distance (75%), and the lingual surface of lateral incisors had the lowest (40%). The distance between the cementoenamel junction and the alveolar bone crest was greater than 2 mm (alveolar bone dehiscence) in 162 (11%) of the 1440 surfaces before orthodontic treatment and in 279 (19%) after treatment.
  
  
  CONCLUSIONS
  The distance from the cementoenamel junction to the bone crest changed after orthodontic treatment; the distance was greater than 2 mm in 11% of the surfaces before treatment and in 19% after treatment.
authors.affiliation: a   Graduate student, School of Dentistry, Federal University of Goiás, Goiânia, GO, Brazil.
authors.forename: Luma O
authors.initials: LO
authors.lastname: Castro
authors.affiliation: a   Graduate student, School of Dentistry, Federal University of Goiás, Goiânia, GO, Brazil.
authors.forename: Iury O
authors.initials: IO
authors.lastname: Castro
authors.affiliation: b   Professor of Endodontics, Department of Oral Science, School of Dentistry, Federal University of Goiás, Goiânia, GO, Brazil.
authors.forename: Ana Helena G
authors.initials: AH
authors.lastname: de Alencar
authors.affiliation: c   Professor of Orthodontics, Department of Preventive and Restorative Dentistry, School of Dentistry, Federal University of Goiás, Goiânia, GO, Brazil.
authors.forename: José
authors.initials: J
authors.lastname: Valladares-Neto
authors.affiliation: d   Professor and Chairman of Endodontics, Department of Oral Science, School of Dentistry, Federal University of Goiás, Goiânia, GO, Brazil.
authors.forename: Carlos
authors.initials: C
authors.lastname: Estrela
mesh_terms: D000539:Alveolar Process / Q000000981:diagnostic imaging*; D054893:Cone-Beam Computed Tomography; D006801:Humans; D007180:Incisor; D008311:Malocclusion, Angle Class I; D019237:Tooth Cervix
keywords: Alveolar bone loss; Cone beam computed tomography; Marginal bone level; Orthodontics; Periodontium