Purpose: In this anatomical study, we compared the diagnostic accuracy of rotational panoramic radiography (OPG), computed tomography (CT) and cone beam computed tomography (CBCT) to the actual anatomical situation.
Materials and methods: Dental images were taken of 10 human cadaver heads. Thereafter, they were prepared and measured. The height of the alveolar ridge to the mandibular canal was compared with the prior images taken. The deviation from the anatomical situation was calculated for each imaging technique.
Results: In the group of OPG images, there was a median of 2.3 mm distortion ranging from -0.2 to 5.7 mm in the vertical plane compared to the actual situation found during dissection. If steel balls were used during OPG, the median distortion was lowered to 0.2 mm, but the width of -1.6 to 3 mm was still quite extensive. CT images showed a mean distortion of -0.2 mm and a width of -1.5 to 1.3 mm. The mean distortion of the CBCT images was similar to the one found in CT, namely -0.3 mm with a range from -1.5 to 0.8 mm.
Conclusions: The results show that OPG using steel balls as a calibration reference seems reliable in a standard situation. In more difficult cases, modern three-dimensional techniques should be used to additionally determine available bone volume.