PSI - Issue 82

Tsanka Dikova et al. / Procedia Structural Integrity 82 (2026) 58–64 Dikova et al. / Structural Integrity Procedia 00 (2026) 000–000

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The pore sizes were investigated by two techniques: Scanning Electron Microscopy Gemini SEM 460 (Carl Zeiss Microscopy, Cambourne, UK) for the surface relief and Conic Beam Computer Tomography (CBCT), allowing measurements in sections inside the sample. CBCT scanner Panmeca proMax (Planmeca, Helsinki, Finland) was used for evaluation of pore sizes. The cubic samples were scanned with the following parameters: slice thickness 0.2 mm; kVp 96; voxel size 0.2/0.2/0.2 mm. The resulting datasets were analyzed with Radiant DICOM viewer (Medixant, Poznań, Poland). On the DICOM images, three sections of each sample were done (Fig. 2). The width of 10 pores on the top and bottom surfaces as well as the 3 sections were measured. The measurements on empty spaces were performed manually by skilled researcher using Length measurement tool with HU values in the interval of -200 - 1000 HE. The images with the measurements were saved as pictures and then analyzed. When working with SEM, 5 pictures in different areas of top and bottom surfaces were taken. The width of 10 pores in each image were measured and the average value was calculated.

Fig. 2. Scheme of planes for investigation of pores morphology by CBCT.

3. Results and Discussion The CBCT images of the 3D printed samples are shown in Fig. 3. It can be clearly seen that the bone samples (Fig. 3a,b,c) are characterized with highly porous structure and high roughness of all surfaces. The pores are interconnected

Fig. 3. CBCT images of: (a), (b) and (c) Group 1 - bone samples; (c), (d) and (f) Group 2 - bone pores samples enlarged with different rate: (a), (d) 0%; (b), (e) 20%; (c), (f) 40 %.