Evaluation of Alveolar Bone Based on CBCT DICOM Datasets

Objectives:

The aim of this study was to evaluate the quality of the alveolar bone by means of quantitative analysis of CBCT datasets. In addition a subjective evaluation of the bone morphology according to the criteria of Lekholm and Zarb was done.

Methods:

CBCT datasets of 30 pig mandibles were acquired by two different CBCT systems (ProMax 3D, Planmeca Oy, Helsinki, Finland and ILUMA CT, IMTEC Imaging, Ardmore, OK, USA). The DICOM datasets were evaluated quantitatively with the ROI tool of a DICOM viewer (eFilm Workstation, Merge Healthcare, Milwaukee, WI, USA). Subjective analysis was done by the help of the same DICOM viewer.

Results:

The quantitative measurements elucidated a large bandwith of pixel values for the CBCT systems. Due to the lower acquisition energy and different reconstructions algortihms the quantitative measurements are not comparable to the representative HU scale generated by CT systems. Subjective analysis delivered overlapping results for both CBCT units.

Conclusions:

Up to now quantitative analysis of alveolar bone can't be done on the base of CBCT datasets. Subjective analysis based on the aforementioned classification is worthless because of the improper analytical potential of the human eye. For a correct prediction of bone quality an exact specification of threedimensional trabecular architecture is needed. This can only be done by means of segmentation of the trabecular network demanding a higher spatial and contrast resolution.