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Your search keyword '"Tingart, Markus"' showing total 829 results
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829 results on '"Tingart, Markus"'

31. Osteointegration of functionalised high-performance oxide ceramics: imaging from micro-computed tomography.

Author

Migliorini, Filippo, Eschweiler, Jörg, Betsch, Marcel, Maffulli, Nicola, Tingart, Markus, Hildebrand, Frank, Lecouturier, Sophie, Rath, Björn, and Schenker, Hanno

Subjects
PROSTHETICS, OSSEOINTEGRATION, BONE density, RESEARCH funding, BONE regeneration, COMPUTED tomography, OLIGOPEPTIDES, ORTHOPEDIC apparatus, BONE morphogenetic proteins, OXIDES, ANIMAL experimentation, DATA analysis software, RABBITS
Abstract

Background: This study evaluated the osseointegration potential of functionalised high-performance oxide ceramics (HPOC) in isolation or coated with BMP-2 or RGD peptides in 36 New Zeeland female rabbits using micro-computed tomography (micro CT). The primary outcomes of interest were to assess the amount of ossification evaluating the improvement in the bone volume/ total volume (BV/TV) ratio and trabecular thickness at 6 and 12 weeks. The second outcome of interest was to investigate possible differences in osteointegration between the functionalised silanised HPOC in isolation or coated with Bone Morphogenetic Protein 2 (BMP-2) or RGD peptides. Methods: 36 adult female New Zealand white rabbits with a minimum weight of three kg were used. One-third of HPOCs were functionalised with silicon suboxide (SiOx), a third with BMP-2 (sHPOC-BMP2), and another third with RGD (sHPOC-RGD). All samples were scanned with a high-resolution micro CT (U-CTHR, MILabs B.V., Houten, The Netherlands) with a reconstructed voxel resolution of 10 µm. MicroCT scans were reconstructed in three planes and processed using Imalytics Preclinical version 2.1 (Gremse-IT GmbH, Aachen, Germany) software. The total volume (TV), bone volume (BV) and ratio BV/TV were calculated within the coating area. Results: BV/TV increased significantly from 6 to 12 weeks in all HPOCs: silanised (P = 0.01), BMP-2 (P < 0.0001), and RGD (P < 0.0001) groups. At 12 weeks, the BMP-2 groups demonstrated greater ossification in the RGD (P < 0.0001) and silanised (P = 0.008) groups. Trabecular thickness increased significantly from 6 to 12 weeks (P < 0.0001). At 12 weeks, BMP-2 promoted greater trabecular thickness compared to the silanised group (P = 0.07), although no difference was found with the RGD (P = 0.1) group. Conclusion: Sinalised HPOC in isolation or functionalised with BMP-2 or RGD promotes in vivo osteointegration. The sinalised HOPC functionalised with BMP-2 demonstrated the greatest osseointegration. [ABSTRACT FROM AUTHOR]

Published
2024
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35. A novel combined level set model for automatic MR image segmentation

Author

Li Jianzhang, Nebelung Sven, Rath Björn, Tingart Markus, and Eschweiler Jörg

Subjects
level set method, mri, segmentation, intensity inhomogeneity, Medicine
Abstract

Medical image processing comes along with object segmentation, which is one of the most important tasks in that field. Nevertheless, noise and intensity inhomogeneity in magnetic resonance images challenge the segmentation procedure. The level set method has been widely used in object detection. The flexible integration of energy terms affords the level set method to deal with variable difficulties. In this paper, we introduce a novel combined level set model that mainly cooperates with an edge detector and a local region intensity descriptor. The noise and intensity inhomogeneities are eliminated by the local region intensity descriptor. The edge detector helps the level set model to locate the object boundaries more precisely. The proposed model was validated on synthesized images and magnetic resonance images of in vivo wrist bones. Comparing with the ground truth, the proposed method reached a Dice similarity coefficient of > 0.99 on all image tests, while the compared segmentation approaches failed the segmentations. The presented combined level set model can be used for the object segmentation in magnetic resonance images.

Published
2020
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36. A pilot study: development of bonepreserving- biomimetic artificial femoral head cover

Author

Siroros Nad, Liu Yu, Lecouturier Sophie, Tingart Markus, and Eschweiler Jörg

Subjects
hip arthroplasty, hip prosthesis, femoral head prosthesis, Medicine
Abstract

Patients with hip arthrosis are increasing each year where total hip replacement is an effective solution when other non-invasive or surgical methods are no longer an effective solution. A pilot study of a new bone-preserving-biomimetic artificial femoral head cover was initiated. The purpose of the new implant is to be an alternative to the current hip arthroplasties. A special polyurethane (PU) femoral head cover was mechanically tested. Experiments were performed to investigate the implants mechanical behaviour and response to tensile load and study on the locking mechanism design concept of the prosthesis. The femoral head cover had a 45 mm outer diameter. Two suture techniques were selected to represent possible locking mechanisms. The experiment consisted of five cyclic loadings followed by a pull-to-failure test. The results show that each specimen has a consistency response and different suture technique results in a different outcome. This experiment intended to study the response of specimens as a whole part, not the material itself. Factors are influencing the outcome such as the femoral head cover positioning and suture rupture pattern. From this pilot study, some points need to be further considered. The information obtained in this experiment would influence further development achieving towards the goal of this alternative hip arthrosis treatment.

Published
2020
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