title: Accuracy of a plastic facial cast fabricated with a custom tray in comparison with cone beam computed tomography.
abstract: OBJECTIVE
  The aim of this study was to test the accuracy of a plaster cast fabricated with a facial custom tray.
  
  
  METHODS
  Sixteen patients with unilateral cleft lip and palate were enrolled in this study. Cone beam computed tomography (CBCT) scanning and facial plaster cast were obtained before surgery. Three-dimensional (3D) coordinates of 6 selected landmarks were recorded directly in CBCT by Mimics and indirectly on the plaster cast by using an electronic caliper and parallel milling machine. The accuracy of the plaster cast was compared with that of CBCT by using the t test and Lin's concordance correlation coefficient. P values less than 0.05 were considered statistically significant.
  
  
  RESULTS
  Horizontal and vertical measurements were larger and sagittal measurements were smaller in plaster cast measurements, but none of these differences was statistically significant (P values ranged from 0.063 to 0.774). Lin's agreement test also showed that the plaster cast had high agreement with CBCT measurements (concordance correlation coefficients ranged from 0.6319 to 0.9599).
  
  
  CONCLUSIONS
  Plaster cast fabricated with a custom tray is an accurate method in facial 3D analysis.
authors.affiliation: Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Jingtao
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Shufan
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Vice Dean, Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, China. Electronic address: shibingchina@sina.com.
authors.forename: Bing
authors.initials: B
authors.lastname: Shi
authors.affiliation: Director, Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zheng
authors.affiliation: Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D002971:Cleft Lip / Q000601:surgery*; D002972:Cleft Palate / Q000601:surgery*; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008953:Models, Anatomic; D011474:Prosthesis Design / Q000379:methods*; D025321:Surgery, Computer-Assisted