Microcomputed Tomography-Based Analysis of Neovascularization within Bioengineered Vascularized Tissues

Volume-stable collagen matrices (VSCM) are conductive for the connective tissue upon soft tissue augmentation. Considering that collagen has osteoconductive properties, we have investigated the possibility that the VSCM also consolidates with the newly formed bone. To this end, we covered nine rat calvaria circular defects with a VSCM. After four weeks, histology, histomorphometry, quantitative backscattered electron imaging, and microcomputed tomography were performed. We report that the overall pattern of mineralization inside the VSCM was heterogeneous. Histology revealed, apart from the characteristic woven bone formation, areas of round-shaped hypertrophic chondrocyte-like cells surrounded by a mineralized extracellular matrix. Quantitative backscattered electron imaging confirmed the heterogenous mineralization occurring within the VSCM. Histomorphometry found new bone to be 0.7 mm2 (0.01 min; 2.4 max), similar to the chondrogenic mineralized extracellular matrix with 0.7 mm2 (0.0 min; 4.2 max). Microcomputed tomography showed the overall mineralized tissue in the defect to be 1.6 mm3 (min 0.0; max 13.3). These findings suggest that in a rat cranial defect, VSCM has a limited and heterogeneous capacity to support intramembranous bone formation but may allow the formation of bone via the endochondral route.

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Comparison of the effects of different instrumentation techniques on root surface roughness and cement loss using microcomputed tomography: An in‐vitro study

International Journal of Dental Hygiene ◽

10.1111/idh.12543 ◽

2021 ◽

Author(s):

Fatma Karacaoglu ◽

Kaan Orhan

Keyword(s):

Surface Roughness ◽

In Vitro Study ◽

Microcomputed Tomography ◽

Root Surface ◽

Vitro Study

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Aluminium Alloy Foam Modelling and Prediction of Elastic Properties Using X-ray Microcomputed Tomography

Metals ◽

10.3390/met11060925 ◽

2021 ◽

Vol 11 (6) ◽

pp. 925

Author(s):

Diogo Heitor ◽

Isabel Duarte ◽

João Dias-de-Oliveira

Keyword(s):

Aluminium Alloy ◽

Finite Element Modelling ◽

Effective Properties ◽

Numerical Models ◽

Microcomputed Tomography ◽

Cellular Materials ◽

Metallic Foams ◽

X Ray ◽

The Impact ◽

Structural Imperfections

X-ray microcomputed tomography has been gaining relevance in the field of cellular materials to characterize materials and analyse their microstructure. So, here, it was used together with finite element modelling to develop numerical models to estimate the effective properties (Young’s modulus) of aluminium alloy foams and evaluate the effects of processing on the results. A manual global thresholding technique using the mass as a quality indicator was used. The models were reconstructed (Marching Cubes 33), then simplified and analysed in terms of mass and shape maintenance (Hausdorff distance algorithm) and face quality. Two simplification procedures were evaluated, with and without small structural imperfections, to evaluate the impact of the procedures on the results. Results demonstrate that the developed procedures are good at minimizing changes in mass and shape of the geometries while providing good face quality, i.e., face aspect ratio. The models are also shown to be able to predict the effective properties of metallic foams in accordance with the findings of other researchers. In addition, the process of obtaining the models and the presence of small structural imperfections were shown to have a great impact on the results.

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