Precision, reproducibility, and accuracy of bone crest level measurements of CBCT cross sections using different resolutions.

OBJECTIVE

To evaluate the precision, reproducibility, and accuracy of alveolar crest level measurements on CBCT images obtained with different voxel sizes.

MATERIALS AND METHODS

CBCT exams were made of 12 dried human mandibles with voxel dimensions of 0.2, 0.3, and 0.4 mm. Bone crest level was measured directly on the mandibles with a digital caliper and on CBCT images. Images were measured twice by two examiners. Intra- and interexaminer precision and reproducibility were assessed using paired and t-tests, respectively. Accuracy was evaluated using t-tests.

RESULTS

Precision and reproducibility of bone crest level tomographic measurements was good for all voxel sizes evaluated. The images with 0.2-mm voxel size showed a decreased number of intraexaminer errors. A high accuracy for measurements of bone crest level was observed for all CBCT definitions, except for the mandibular incisors using the 0.4-mm voxel size.

CONCLUSIONS

Precision and reproducibility of alveolar bone level measurements were good for various voxel sizes. CBCT images demonstrated good accuracy for 0.2-mm and 0.3-mm voxel sizes. The mandibular incisor region needs better resolution than that provided by 0.4-mm voxel size for bone crest level measurements.