title: Distraction osteogenesis for cleft palate closure: A finite element analysis.
abstract: BACKGROUND
  Current methods of closure of the cleft palate result in the formation of scars and impairment of growth. Distraction osteogenesis (DO) might be an effective means to repair or at least reduce the size of wide clefts. This study investigates the biomechanical aspects of this process.
  
  
  METHODS
  DO simulation was applied to reduce the size of a unilateral hard palate cleft on a three-dimensional (3D) model of the maxilla. For the position of osteotomy lines, two different models were assumed, with the osteotomy line on the affected side in model A and on the intact side in model B. In each model, DO screws were placed on two different positions, anteriorly (models A1 and B1) and posteriorly (models A2 and B2). Displacement pattern of the bony island in each of the four models, reaction forces at DO locations, and von Mises stress were estimated. Mesh generation and data processing were carried out in the 3D finite element analysis package (ABAQUS V6.7-1; Simulia Corp., Providence, RI, USA).
  
  
  RESULTS
  In model B2, the island moved almost evenly, assuring a more complete closure of the cleft. The most uniform stress distribution was found in model B1.
  
  
  CONCLUSIONS
  The results suggest that the best positions for the DO screw and the osteotomy line for closure of the cleft palate are posteriorly and on the intact side, respectively.
authors.affiliation: Dental Research center, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Ghasemianpour
authors.affiliation: Dental Research center, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Ehsani
authors.affiliation: Department of Orthodontics, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Soodeh
authors.initials: S
authors.lastname: Tahmasbi
authors.affiliation: Craniomaxillofacial Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Bayat
authors.affiliation: Department of Oral & Maxillofacial pathology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Maedeh
authors.initials: M
authors.lastname: Ghorbanpour
authors.affiliation: Dental Research center, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Seyed Mohammadreza
authors.initials: SM
authors.lastname: Safavi
authors.affiliation: Department of Agricultural Engineering, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: Fatemeh Sadat
authors.initials: FS
authors.lastname: Mirhashemi
keywords: Cleft palate; distraction osteogenesis; finite element analysis