title: Precise insertion of orthodontic miniscrews with a stereolithographic surgical guide based on cone beam computed tomography data: a pilot study.
abstract: OBJECTIVE
  Orthodontic miniscrews are commonly used to achieve absolute anchorage during tooth movement. One of the most frequent complications is screw loss as a result of root contact. Increased precision during the process of miniscrew insertion would help prevent screw loss and potential root damage, improving treatment outcomes. Stereolithographic surgical guides have been commonly used for prosthetic implants to increase the precision of insertion. The objective of this paper was to describe the use of a stereolithographic surgical guide suitable for one-component orthodontic miniscrews based on cone beam computed tomography (CBCT) data and to evaluate implant placement accuracy.
  
  
  METHODS
  Acrylic splints were adapted to the dental arches of four patients, and six radiopaque reference points were filled with gutta-percha. The patients were submitted to CBCT while they wore the occlusal splint. Another series of images was captured with the splint alone. After superimposition and segmentation, miniscrew insertion was simulated using planning software that allowed the user to check the implant position in all planes and in three dimensions. In a rapid-prototyping machine, a stereolithographic guide was fabricated with metallic sleeves located at the insertion points to allow for three-dimensional control of the pilot bur. The surgical guide was worn during surgery. After implant insertion, each patient was submitted to CBCT a second time to verify the implant position and the accuracy of the placement of the miniscrews.
  
  
  RESULTS
  The average differences between the planned and inserted positions for the ten miniscrews were 0.86 mm at the coronal end, 0.71 mm at the center, and 0.87 mm at the apical tip. The average angular discrepancy was 1.76 degrees.
  
  
  CONCLUSIONS
  The use of stereolithographic surgical guides based on CBCT data allows for accurate orthodontic mini screw insertion without damaging neighboring anatomic structures.
authors.affiliation: Department of Orthodontics, Dentistry Faculty, University of São Paulo, Brazil. cmorea@uol.com.br
authors.forename: Camillo
authors.initials: C
authors.lastname: Morea
authors.forename: Jorge Elias
authors.initials: JE
authors.lastname: Hayek
authors.forename: Cesar
authors.initials: C
authors.lastname: Oleskovicz
authors.forename: Gladys Cristina
authors.initials: GC
authors.lastname: Dominguez
authors.forename: Israel
authors.initials: I
authors.lastname: Chilvarquer
mesh_terms: D001863:Bone Screws; D054893:Cone-Beam Computed Tomography; D057918:Fiducial Markers; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008334:Mandible / Q000601:surgery; D008437:Maxilla / Q000601:surgery; D008953:Models, Anatomic; D017090:Occlusal Splints; D019647:Oral Surgical Procedures / Q000295:instrumentation / Q000379:methods*; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D010347:Patient Care Planning; D010865:Pilot Projects