Statement of Problem: Image distortion in intra and extra-oral radiographs are an unavoidable phenomenon. Patient's positional changes from the routine alignments is an important issue for this unwanted alteration, Therefore the accuracy of the dimensional measurements will be affected.
Purpose: Our purpose is to find out the effect of minor changes (possibly happening in the clinic) in the position of a human dry skull on the accuracy of the measurements acquired by Cone Beam Computed Tomography (CBCT).
Materials and Method: In this study, 3 locations on the skull were pointed with radio- opaque markers. Imaging process with Kodak 9000 CBCT was performed in standard and 10 analytically miss- oriented positions. Then 2 distances were measured between the centers of markers. Later, these measurements were compared with the standard position values.
Results: There was not any imperative difference in the measurements of the 10 altered positions yielded in this study with standard position values.
Conclusion: According to our results, apparently, the accuracy of linear measurements in CBCT images is endorsed by unintentional small changes in the patient’s position during the projections.