title: Surgical positioning of orthodontic mini-implants with guides fabricated on models replicated with cone-beam computed tomography.
abstract: BACKGROUND
  This article illustrates a new surgical guide system that uses cone-beam computed tomography (CBCT) images to replicate dental models; surgical guides for the proper positioning of orthodontic mini-implants were fabricated on the replicas, and the guides were used for precise placement. The indications, efficacy, and possible complications of this method are discussed.
  
  
  METHODS
  Patients who were planning to have orthodontic mini-implant treatment were recruited for this study. A CBCT system (PSR 9000N, Asahi Roentgen, Kyoto, Japan) was used to acquire virtual slices of the posterior maxilla that were 0.1 to 0.15 mm thick. Color 3-dimensional rapid prototyping was used to differentiate teeth, alveolus, and maxillary sinus wall. A surgical guide for the mini-implant was fabricated on the replica model. Proper positioning for mini-implants on the posterior maxilla was determined by viewing the CBCT images.
  
  
  RESULTS
  The surgical guide was placed on the clinical site, and it allowed precise pilot drilling and accurate placement of the mini-implant.
  
  
  CONCLUSIONS
  CBCT imaging allows remarkably lower radiation doses and thinner acquisition slices compared with medical computed tomography. Virtually reproduced replica models enable precise planning for mini-implant positions in anatomically complex sites.
authors: Department of Orthodontics, Catholic University of Korea, Uijongbu St. Mary's Hospital, Seoul, Korea. bravortho@catholic.ac.kr
authors: Seong-Hun
authors: SH
authors: Kim
authors: Yong-Suk
authors: YS
authors: Choi
authors: Eui-Hwan
authors: EH
authors: Hwang
authors: Kyu-Rhim
authors: KR
authors: Chung
authors: Yoon-Ah
authors: YA
authors: Kook
authors: Gerald
authors: G
authors: Nelson
mesh_terms: D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D006801:Humans; D021621:Imaging, Three-Dimensional; D008437:Maxilla / Q000033:anatomy & histology; D008904:Miniaturization; D008953:Models, Anatomic; D003765:Models, Dental; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D015921:Dental Implants