title: Three-dimensional finite element analysis of the craniomaxillary complex during maxillary protraction with bone anchorage vs conventional dental anchorage.
abstract: BACKGROUND
  The aim of this study was to explore the biomechanical effects on the craniomaxillary complex of bone anchorage and dental anchorage during maxillary protraction.
  
  
  METHODS
  We established 2 finite element models. One simulated maxillary protraction with dental anchorage in the maxillary first molars and the other with bone anchorage in the infrazygomatic buttresses of the maxilla. The magnitude of the applied forces was 500 g per side, and the force directions were 0°, 10°, 20°, and 30° forward and downward relative to the occlusal plane.
  
  
  RESULTS
  The finite element model of the craniomaxillary complex could displace in an almost translatory manner when the force direction was about 20° in the bone anchorage model and about 30° in the dental anchorage model. The nodes representing the sutures at the back of the maxilla showed greater stress in the bone anchorage model than in the dental anchorage model in the same force direction. It is the opposite at the front of the maxilla.
  
  
  CONCLUSIONS
  We should determine the direction of applied force according to the anchorage location and skeletal characteristics of patients before maxillary protraction. The dramatic effects of maxillary protraction with bone anchorage can be based on the advantages of bone anchorage, not on the changes in the region of the applied force.
authors: Department of Orthodontics, School of Stomatology, China Medical University, Shenyang, Liaoning, China.
authors: Xiulin
authors: X
authors: Yan
authors: Weijun
authors: W
authors: He
authors: Tao
authors: T
authors: Lin
authors: Jun
authors: J
authors: Liu
authors: Xiaofeng
authors: X
authors: Bai
authors: Guangqi
authors: G
authors: Yan
authors: Li
authors: L
authors: Lu
mesh_terms: D001696:Biomechanical Phenomena; D002508:Cephalometry; D003198:Computer Simulation; D003799:Dental Stress Analysis; D005115:Extraoral Traction Appliances; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional; D008313:Malocclusion, Angle Class III / Q000628:therapy*; D008437:Maxilla; D008953:Models, Anatomic; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design