[Computer-aided reconstruction of the facial skeleton : Planning and implementation in clinical routine].

In computer-aided reconstruction of the facial skeleton, a workflow has been established involving the following steps: > diagnosis → planning and simulation → surgical procedure → validation and quality control <. In addition to clinical findings, the focus of diagnosis is on three-dimensional (3D) imaging, particularly computed tomography. Planning and simulation involves creation of a virtual model of the desired surgical outcome using special planning software. The accuracy of implant fit can be virtually verified before surgery. 3D models and virtual reconstructions can be used for manufacturing patient-specific implants. During the surgical procedure, planning must be transferred to the surgical site as accurately as possible. A number of techniques are available for this purpose, e. g., closed reduction, open reduction with the placement of anatomically preformed or patient-specific implants in combination with surgical guides, and the additional use of navigation. Validation and quality control require postprocedural 3D imaging. After reconstructions of the midface, 3D imaging should be performed even before surgery is completed. Malpositions can thus be directly corrected and unnecessary open reconstructions avoided. Mobile 3D c-arms are particularly useful for intraoperative 3D imaging. Whereas intraoperative imaging makes postoperative imaging after midface reconstruction unnecessary in many cases, postoperative 3D imaging in addition to intraoperative imaging may still be recommended after complex reconstructions of the facial skeleton.