Integration of three-dimensional cephalometry and 3D-skull models in combined orthodontic/surgical treatment planning

In 15 adult patients with severe dentomaxillofacial deformities we integrated 3-dimensional cephalometry and 3D-model surgery with individually milled or stereolithographically built skull models in our combined orthodontic/surgical diagnosis and treatment planning. After the generation of contiguous axial CT-scans the CT data sets were transferred to a commonly used computing system (IBM-PC) to reconstruct 3D-images from any point of view. After the definition of measurement points, distances and angles at the skin and bone surface a 3-dimensional cephalometric analysis could be performed directly in the 3D-objects on the monitor. This allows a quantitative assessment of skeletal asymmetries. The transfer of CT data to life-size 3D-skull models and replacement of imprecise dental arches by dental casts different orthodontic and surgical treatment concepts could be evaluated. The 3D-model surgery represents a new quality of treatment prediction in the individual dentomaxillofacial morphology. The orthodontic set-up and 3D-model surgery permit a verification of the feasibility of the most suitable mobilization and placement of bone segments. The clinical treatment sequences indicated that the integration of 3-dimensional cephalometry and 3D-model surgery in patients with severe asymmetric dentomaxillofacial deformities allowed a higher precision of diagnosis and treatment planning.