Three-dimensional analysis in facial asymmetry: comparison with model analysis and conventional two-dimensional analysis

The purpose of this study was to compare a computed tomographic (CT) three-dimensional analysis with a model analysis to use it as diagnostic aid for the evaluation of occlusal plane tilting in facial asymmetry. Ten patients with facial asymmetry underwent CT three-dimensional examination, plaster cast analysis, and two-dimensional cephalometric analysis. The distance between a reference plane to the upper first molar and upper canine was measured on three-dimensional CT, on models, and on cephalograms to assess occlusal plane tilting. Measurements taken on three-dimensional CT were compared with those taken on articulator and cephalograms, and the level of discordance between the different analyses was evaluated. Quantitative data on the occlusal tilting are similar, but three-dimensional CT gives a better representation of anatomy, thus reducing interpretative problems about altered individual anatomy. Three-dimensional CT seems to be so helpful in detecting individual anatomical variations that it can be adopted in the diagnosis for severe craniofacial asymmetry.