title: Evaluation of a semiburied, fixed-trajectory, curvilinear, distraction device in an animal model.
abstract: OBJECTIVE
  This study evaluated a new small, buried distractor, capable of curvilinear movement while following a fixed trajectory. The geometrical basis for such devices and the 3-dimensional treatment planning system required to make buried distractors practical are discussed.
  
  
  METHODS
  A curved rack and worm-gear device, based on the design of a hose clamp, was constructed to produce a curved distraction path, and this distractor was tested in 2 minipigs using a protocol with zero latency and 1 mm/d x 7 days of distraction. Serial standardized lateral cephalograms were used to verify distractor function and path.
  
  
  RESULTS
  Curvilinear distraction was documented by clinical examination and serial cephalometric analysis in the 2 minipigs. Observed angulation of the margins of the wedge-shaped distraction gap conformed to the calculated angulation based on the fixed radius of curvature of the distractor.
  
  
  CONCLUSIONS
  Distraction along a curved trajectory using a small, semiburied, curvilinear device of novel design is feasible in the minipig mandible.
authors.affiliation: Department of Oral & Maxillofacial Surgery, Massachusetts General Hospital and Harvard School of Dental Medicine, Boston 02114, USA. Seldin.Edward@MGH.Harvard.edu
authors.forename: E B
authors.initials: EB
authors.lastname: Seldin
authors.forename: M J
authors.initials: MJ
authors.lastname: Troulis
authors.forename: L B
authors.initials: LB
authors.lastname: Kaban
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004867:Equipment Design; D005240:Feasibility Studies; D016268:Internal Fixators; D008334:Mandible / Q000601:surgery*; D019857:Osteogenesis, Distraction / Q000295:instrumentation* / Q000379:methods; D013552:Swine; D013556:Swine, Miniature