A Determination of the Accuracy of Cone Beam Computed Tomography

Objective: The purpose of this study was to compare the accuracy of cone beam CT (CBCT) imaging with digital orthopantomograms for determining bone quantity in the mandibular ramus. Methods: Twenty-nine cadaveric mandibles marked bilaterally with three fiducial markers were imaged using both CBCT and digital orthopantomography. After sectioning, four cross sectional measurements were made on the specimens and on the CBCT images. Two corresponding linear measurements were made on the orthopantomograms. Statistical analysis was used to compare the CBCT and orthopantomogram measurements with measurements from the anatomic specimens. Results: CBCT measurements were found to significantly differ from those made on the anatomic specimens (P<0.05). Linear measurements from the orthopantomograms varied by 15.9 percent compared to the anatomic specimens. Conclusion: CBCT and orthopantomogram measurements were significantly different from those of the anatomic specimens suggesting inaccuracies in the radiographic technology or a lack of precision in landmark identification.