Assessments of trabecular bone density at implant sites on CT images

Objectives. To evaluate the association between trabecular bone density measurements of potential implant sites made on axial DICOM images ( DentaCT software) and on the same images with eFilm workstation, to correlate bone densities in Hounsfield units ( HU) with subjective classification, and to establish a quantitative scale for each bone quality class. Study design. Twenty-seven maxillary and 27 mandibular computed tomographic ( CT) examinations of 75 potential implant sites were selected. Trabecular bone density was evaluated with DentaCT and eFilm. Bone quality was subjectively evaluated by 2 examiners. Descriptive statistics, between- and within-group comparison, correlation analysis, and Bland-Altman plot were used for data analysis. Results. DentaCT measurements were higher than eFilm ( P <.001). Bone type 2 was the most prevalent, and bone density was significantly reduced from bone types 1 to 4. Quantitative parameters ranged as follows: bone type 4 < 200 HU, bone types 2 and 3 > 200 to < 400 HU, and bone type 1 > 400 HU. Conclusion. Different qualities of bone can be found in any of the anatomical regions studied ( anterior and posterior sites of maxilla and mandible), which confirms the importance of a site-specific bone tissue evaluation prior to implant installation.