Analysis of trabecular bone using site-specific fractal values calculated from cone beam CT images

The purpose of the study was to explore the use of cone beam CT (CBCT) images to calculate fractal values of trabecular bone. Seventy-nine CBCT scans were used. Seven sites were selected from each scan. These sites were: coronal views of the (1) right and (2) left side of the mandible; coronal views of the (3) right and (4) left maxilla; axially corrected coronal views of the (5) right and (6) left condylar heads through the largest width, and (7) a sagittal section through the second cervical vertebral (C2) body. Fractal values were calculated from a total of 553 images using the box-counting method. These values were categorized and analyzed for site- and gender-specific differences. Fractal values decreased in most of the sites with increasing age. Values in males were generally higher than those in females. Values did not change significantly from right side to left side of the jaw. However, values from the mandible, maxilla, condyle and C2 vertebrae differed significantly from each other, suggesting a site-specific nature of the fractal value (p < 0.001). The lowest and highest fractal values were in the mandible and C2 vertebrae, respectively (1.313 and 1.536, respectively). Fractal values can detect differences in the trabecular bone morphology in different parts of the jaw. Fractal values can potentially be used for objective analysis of the trabecular bone using CBCT images.