title: Three-dimensional evaluations of supernumerary teeth using cone-beam computed tomography for 487 cases.
abstract: OBJECTIVE
  The purpose of this article is to introduce the use of cone-beam computed tomography (CBCT) for evaluation of supernumerary teeth.
  
  
  METHODS
  The study group comprised 487 patients with a total of 626 supernumerary teeth who were examined by CBCT. Patient characteristics were recorded, and the number, location, shape, and 3-dimensional position of the supernumeraries were analyzed. The ability of CBCT to visualize dental and skeletal structures relative to supernumerary teeth was also evaluated.
  
  
  RESULTS
  Males were affected more than females in a ratio of 2.64:1. Seventy-two percent of the patients had 1 supernumerary tooth, 27.3% had 2, and 0.6% had 3 supernumeraries. Supernumerary teeth were most frequently located in the anterior maxilla (92%), and their sagittal location relative to the neighboring teeth could be used for classification purposes. Supernumeraries were most commonly conical in shape (83.5%). CBCT yielded accurate 3-dimensional pictures of the dental and bony structures. The sagittal positions of the 578 supernumerary teeth in the anterior maxilla were divided into 6 types, of which types I and III were most commonly associated with local malocclusions. Moreover, 43.4% of the premaxillary supernumeraries were inverted and 21.1% were transversely oriented.
  
  
  CONCLUSIONS
  CBCT imaging yields accurate 3-dimensional pictures of local dental and bony structures, which is helpful for pretreatment evaluation of supernumerary teeth.
authors.affiliation: Department of Oral Radiology, Peking University School and Hospital of Stomatology, Beijing, China. kqldg@bjmu.edu.cn <kqldg@bjmu.edu.cn>
authors.forename: Deng-gao
authors.initials: DG
authors.lastname: Liu
authors.forename: Wan-lin
authors.initials: WL
authors.lastname: Zhang
authors.forename: Zu-yan
authors.initials: ZY
authors.lastname: Zhang
authors.forename: Yun-tang
authors.initials: YT
authors.lastname: Wu
authors.forename: Xu-chen
authors.initials: XC
authors.lastname: Ma
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008310:Malocclusion / Q000209:etiology; D019252:Radiography, Dental, Digital / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014096:Tooth, Supernumerary / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology*