A Study of 3D Reconstruction, Orthognathic Surgery Simulation and Forecast System of Craniofacial Hard and Soft Tissue Based on Cephalograms and Laser Scanning

  • Dr Yuxia Hou, Department of Orthodontics, Stomatological Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China, Chinese Orthodontic Society
  • Dr Hong Zhou, Department of Orthodontics, Stomatological Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China, Chinese Orthodontic Society
  • Prof Yanning Zhang, Computer Department of Northwestern Polytechnical University, Xi’an, China, Chinese Orthodontic Society
  • Dr Yaopu Feng, Department of Orthodontics, Stomatological Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, P. R. China, Chinese Orthodontic Society

Objective: The aim was to reconstruct the three-dimensional model of craniofacial hard and soft tissue based on cephalograms and laser scanning;to found the 3D measurement and orthognathic simulation and forcast system.
Methods: 3D digitizer (Minolta VIVID910) and image software (Rapidform 2004) were used to scan and reconstruct the 3D model of craniofacial soft tissue. 3D measuring software was developed by Visual C++. Posteranterior and lateral cephalograms were taken for constructing 3D craniofacial skeletal model,which were adjusted to consistent with the coordinate system of a standard CT model. And then the 3D model of craniofacial skeletal tissue was achieved through deforming the standard model according to the 64 feature points. Based on 5 lead points setting on the surface and the feature point, craniofacial soft tissue, skeletal tissue and teeth were constructed together in one model.
Results: 52 landmarks and 129 measurement items could be done in the laser scanning measuring system. We also developed 3D orthognathic surgery simulation and forecast system based on the craniofacial hard and soft tissue model. The system could predict craniofacial soft tissue deformation precisely according to contrast research between prediction and actual deformation of soft tissue.
Conclusions:The whole system completed the functions of three-dimensional reconstruction, accuracy validation,orthognathic surgery simulation and forecast. That may provide a new method for analysis of maxillofacial malformation, and for the quantity control and evaluation of the orthodontic treatment, orthopedics and plastic operation.