Maxillofacial 3-dimensional image analysis for the diagnosis of facial asymmetry.

The advent of computed tomography has greatly reduced magnification errors from geometric distortions that are common in conventional radiographs. Recently introduced 3-dimensional (3D) software enables 3D reconstruction and quantitative measurement of the maxillofacial complex; 3D images are also useful in understanding asymmetrical structures. This article describes the use of 3D images in the diagnosis of facial asymmetry. A step-by-step procedure for 3D analysis developed by the authors is described by using the example of a 23-year-old man with a chin deviation to 1 side.