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cephalometric analysis based on natural head posture Remains valid over time compared with intracranial Reference planes to the vertical
2. Errors of Identification Result from many factors: ●e an‘envelope of error’which is dependent on : i.anatomic characteristics of landmark,points on edges are easier to locate than points within structures as superimposition is less ii.differing definition of landmark,influenced by understanding and experience iii.quality of image,easier point location with clearer images Most reliable point-sella Least reliable points-lower incisor apex;gonion ● method of registration-see earlier section ●operator reliability-influenced by experience and Calibration
cephalometric analysis used-different methods available,some more complicated than others,method chosen should reflect clinical/research use ● environment-light box used,ambient light conditions