Evaluation of segmentation methods for bone implant screws on in-vivo μCT data in the MgBone study – methodological evaluation of performance and repeatability for screw materials

Here, we present a bone implant system of phase-oriented titanium dioxide (TiO2) fabricated by the micro-arc oxidation method (MAO) on β-Ti to facilitate improved osseointegration. This (101) rutile-phase-dominant MAO TiO2 (R-TiO2) is biocompatible due to its high surface roughness, bone-mimetic structure, and preferential crystalline orientation. Furthermore, (101) R-TiO2 possesses active and abundant hydroxyl groups that play a significant role in enhancing hydroxyapatite formation and cell adhesion and promote cell activity leading to osseointegration. The implants had been elicited their favorable cellular behavior in vitro in the previous publications; in addition, they exhibit excellent shear strength and promote bone–implant contact, osteogenesis, and tissue formation in vivo. Hence, it can be concluded that this MAO R-TiO2 bone implant system provides a favorable active surface for efficient osseointegration and is suitable for clinical applications.

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Influence of calcium ion-modified implant surfaces in protein adsorption and implant integration

International Journal of Implant Dentistry ◽

10.1186/s40729-021-00314-1 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Eduardo Anitua ◽

Andreia Cerqueira ◽

Francisco Romero-Gavilán ◽

Iñaki García-Arnáez ◽

Cristina Martinez-Ramos ◽

...

Keyword(s):

Protein Adsorption ◽

Titanium Implant ◽

Volume Density ◽

Bone Implant ◽

The Mean ◽

Intervention Costs ◽

Medial Section ◽

Post Implantation

Abstract Background Calcium (Ca) is a well-known element in bone metabolism and blood coagulation. Here, we investigate the link between the protein adsorption pattern and the in vivo responses of surfaces modified with calcium ions (Ca-ion) as compared to standard titanium implant surfaces (control). We used LC–MS/MS to identify the proteins adhered to the surfaces after incubation with human serum and performed bilateral surgeries in the medial section of the femoral condyles of 18 New Zealand white rabbits to test osseointegration at 2 and 8 weeks post-implantation (n=9). Results Ca-ion surfaces adsorbed 181.42 times more FA10 and 3.85 times less FA12 (p<0.001), which are factors of the common and the intrinsic coagulation pathways respectively. We also detected differences in A1AT, PLMN, FA12, KNG1, HEP2, LYSC, PIP, SAMP, VTNC, SAA4, and CFAH (p<0.01). At 2 and 8 weeks post-implantation, the mean bone implant contact (BIC) with Ca-ion surfaces was respectively 1.52 and 1.25 times higher, and the mean bone volume density (BVD) was respectively 1.35 and 1.13 times higher. Differences were statistically significant for BIC at 2 and 8 weeks and for BVD at 2 weeks (p<0.05). Conclusions The strong thrombogenic protein adsorption pattern at Ca-ion surfaces correlated with significantly higher levels of implant osseointegration. More effective implant surfaces combined with smaller implants enable less invasive surgeries, shorter healing times, and overall lower intervention costs, especially in cases of low quantity or quality of bone.

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Osseointegration of a novel dental implant in canine

Scientific Reports ◽

10.1038/s41598-021-83700-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lingxiao Wang ◽

Zhenhua Gao ◽

Yucheng Su ◽

Qian Liu ◽

Yi Ge ◽

...

Keyword(s):

Volume Ratio ◽

Volume Density ◽

Scientific Basis ◽

Bone Volume ◽

Trabecular Thickness ◽

Bone Implant ◽

Further Development ◽

Trabecular Number ◽

Histological Staining

AbstractThis study aimed to compare and verify the osseointegration performance of a novel implant (NI) in vivo, which could provide a useful scientific basis for the further development of NIs. Thirty-two NIs treated with hydrofluoric acid and anodization and sixteen control implants (CIs) were placed in the mandibles of 8 beagles. Micro-CT showed that the trabecular number (Tb.N) significantly increased and trabecular separation (Tb.Sp) significantly decreased in the NIs at 2 weeks. Significant differences were found in the trabecular thickness, Tb.N, Tb.Sp, bone surface/bone volume ratio, and bone volume/total volume ratio between the two groups from the 2nd–4th weeks. However, there were no significant differences between the two groups in the bone volume density at 2, 4, 8, or 12 weeks or bone-implant contact at 2 or 4 weeks, but the BIC in the CIs was higher than that in the NIs at the 8th and 12th weeks. Meanwhile, the histological staining showed a similar osseointegration process between the two groups over time. Overall, the NIs could be used as new potential implants after further improvement.

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Periprosthetic Osteolysis: Mechanisms, Prevention and Treatment

Journal of Clinical Medicine ◽

10.3390/jcm8122091 ◽

2019 ◽

Vol 8 (12) ◽

pp. 2091 ◽

Cited By ~ 14

Author(s):

Stuart B. Goodman ◽

Jiri Gallo

Keyword(s):

Nuclear Factor Κb ◽

Nuclear Factor ◽

Activator Protein 1 ◽

Periprosthetic Osteolysis ◽

Bone Implant ◽

Joint Replacements ◽

In Vivo Experiments ◽

Mechanical Factors

Clinical studies, as well as in vitro and in vivo experiments have demonstrated that byproducts from joint replacements induce an inflammatory reaction that can result in periprosthetic osteolysis (PPOL) and aseptic loosening (AL). Particle-stimulated macrophages and other cells release cytokines, chemokines, and other pro-inflammatory substances that perpetuate chronic inflammation, induce osteoclastic bone resorption and suppress bone formation. Differentiation, maturation, activation, and survival of osteoclasts at the bone–implant interface are under the control of the receptor activator of nuclear factor kappa-Β ligand (RANKL)-dependent pathways, and the transcription factors like nuclear factor κB (NF-κB) and activator protein-1 (AP-1). Mechanical factors such as prosthetic micromotion and oscillations in fluid pressures also contribute to PPOL. The treatment for progressive PPOL is only surgical. In order to mitigate ongoing loss of host bone, a number of non-operative approaches have been proposed. However, except for the use of bisphosphonates in selected cases, none are evidence based. To date, the most successful and effective approach to preventing PPOL is usage of wear-resistant bearing couples in combination with advanced implant designs, reducing the load of metallic and polymer particles. These innovations have significantly decreased the revision rate due to AL and PPOL in the last decade.

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In Vivo and In Vitro Evaluation of Coated HAp Films with Different Surface Morphology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.710 ◽

2007 ◽

Vol 539-543 ◽

pp. 710-715

Author(s):

Kotaro Kuroda ◽

Ryoichi Ichino ◽

Masazumi Okido

Keyword(s):

Bone Formation ◽

Surface Morphology ◽

New Bone Formation ◽

Contact Ratio ◽

Bone Implant ◽

Ft Ir ◽

Mouse Osteoblast ◽

Surface Morphologies

Hydroxyapatite (HAp) coatings were formed on cp titanium plates and rods by the thermal substrate method in an aqueous solution that included 0.3 mM Ca(H2PO4)2 and 0.7 mM CaCl2. The coating experiments were conducted at 40-140 oC and pH = 8 for 15 or 30 min. The properties for the coated samples were studied using XRD, EDX, FT-IR, and SEM. All the specimens were covered with HAp, which had different surface morphologies such as net-like, plate-like and needle-like. After cleaning and sterilization, all the coated specimens were subjected to in vivo and vitro testing. In the in vitro testing, the mouse osteoblast-like cells (MC3T3-E1) were cultured on the coated and non-coated specimens for up to 30 days. Moreover, the specimens (φ2 x 5 mm) were implanted in rats femoral for up to 8 weeks, the osseoinductivity on them were evaluated. In in vitro evaluations, there were not significant differences between the different surface morphologies. In in vivo evaluations, however, two weeks postimplantation, new bone formed on both the HAp coated and non-coated titanium rods in the cancellous and cortical bone. The bone-implant contact ratio, which was used for the evaluation of new bone formation, was significantly dependent on the surface morphology of the HAp, and the results demonstrated that the needle-like coating appears to promote rapid bone formation.

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Comparison of the Resistance to Bending Forces of the 4.5 LCP Plate-rod Construct and of 4.5 LCP Alone Applied to Segmental Femoral Defects in Miniature Pigs

Acta Veterinaria Brno ◽

10.2754/avb201079040613 ◽

2010 ◽

Vol 79 (4) ◽

pp. 613-620 ◽

Cited By ~ 2

Author(s):

Lucie Urbanová ◽

Robert Srnec ◽

Pavel Proks ◽

Ladislav Stehlík ◽

Zdeněk Florian ◽

...

Keyword(s):

Ex Vivo ◽

Femoral Diaphysis ◽

Miniature Pig ◽

Femoral Bone ◽

Bone Implant ◽

Miniature Pigs ◽

Bone Defect Healing ◽

Considerable Strain

The study deals with the determination of mechanical properties, namely resistance to bending forces, of flexible buttress osteosynthesis using two different bone-implant constructs stabilizing experimental segmental femoral bone defects (segmental ostectomy) in a miniature pig ex vivo model using 4.5 mm titanium LCP and a 3 mm intramedullary pin (“plate and rod” construct) (PR-LCP), versus the 4.5 mm titanium LCP alone (A-LCP). The “plate and rod” fixation (PR-LCP) of the segmental femoral defect is significantly more resistant (p < 0.05) to bending forces (200 N, 300 N, and 500 N) than LCP alone (A-LCP). Stabilisation of experimental segmental lesions of the femoral diaphysis in miniature pigs by flexible bridging osteosynthesis 4.5 mm LCP in combination with the “plate and rod” construct appears to be a suitable fixation of non-reducible fractures where considerable strain of the implants by bending forces can be assumed. These findings will be used in upcoming in vivo experiments in the miniature pig to investigate bone defect healing after transplantation of mesenchymal stem cells in combination with biocompatible scaffolds.

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In vivo degradation behavior of Ca-deficient hydroxyapatite coated Mg–Zn–Ca alloy for bone implant application

Colloids and Surfaces B Biointerfaces ◽

10.1016/j.colsurfb.2011.06.040 ◽

2011 ◽

Vol 88 (1) ◽

pp. 254-259 ◽

Cited By ~ 78

Author(s):

Huanxin Wang ◽

Shaokang Guan ◽

Yisheng Wang ◽

Hongjian Liu ◽

Haitao Wang ◽

...

Keyword(s):

Degradation Behavior ◽

Bone Implant ◽

In Vivo Degradation

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Quantification of vascular networks in photoacoustic mesoscopy

10.1101/2021.11.22.469541 ◽

2021 ◽

Author(s):

Emma L Brown ◽

Thierry L Lefebvre ◽

Paul W Sweeney ◽

Bernadette Stolz ◽

Janek Gröhl ◽

...

Keyword(s):

Blood Volume ◽

Network Structure ◽

In Silico ◽

Ex Vivo ◽

Image Filtering ◽

Vascular Networks ◽

Ground Truth Data ◽

Rule Based ◽

Segmentation Methods

Mesoscopic photoacoustic imaging (PAI) enables non-invasive visualisation of tumour vasculature and has the potential to assess prognosis and therapeutic response. Currently, evaluating vasculature using mesoscopic PAI involves visual or semi-quantitative 2D measurements, which fail to capture 3D vessel network complexity, and lack robust ground truths for assessment of segmentation accuracy. Here, we developed an in silico, phantom, in vivo, and ex vivo-validated end-to-end framework to quantify 3D vascular networks captured using mesoscopic PAI. We applied our framework to evaluate the capacity of rule-based and machine learning-based segmentation methods, with or without vesselness image filtering, to preserve blood volume and network structure by employing topological data analysis. We first assessed segmentation performance against ground truth data of in silico synthetic vasculatures and a photoacoustic string phantom. Our results indicate that learning-based segmentation best preserves vessel diameter and blood volume at depth, while rule-based segmentation with vesselness image filtering accurately preserved network structure in superficial vessels. Next, we applied our framework to breast cancer patient-derived xenografts (PDXs), with corresponding ex vivo immunohistochemistry. We demonstrated that the above segmentation methods can reliably delineate the vasculature of 2 breast PDX models from mesoscopic PA images. Our results underscore the importance of evaluating the choice of segmentation method when applying mesoscopic PAI as a tool to evaluate vascular networks in vivo.

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Comparison and Supervised Learning of Segmentation Methods Dedicated to Specular Microscope Images of Corneal Endothelium

International Journal of Biomedical Imaging ◽

10.1155/2014/704791 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 4

Author(s):

Yann Gavet ◽

Jean-Charles Pinoli

Keyword(s):

Image Segmentation ◽

Cell Layer ◽

Spatial Density ◽

Specular Microscopy ◽

Main Criterion ◽

Segmentation Methods ◽

Best Parameter ◽

Good Transparency ◽

Parameter Values

The cornea is the front of the eye. Its inner cell layer, called the endothelium, is important because it is closely related to the light transparency of the cornea. An in vivo observation of this layer is performed by using specular microscopy to evaluate the health of the cells: a high spatial density will result in a good transparency. Thus, the main criterion required by ophthalmologists is the cell density of the cornea endothelium, mainly obtained by an image segmentation process. Different methods can perform the image segmentation of these cells, and the three most performing methods are studied here. The question for the ophthalmologists is how to choose the best algorithm and to obtain the best possible results with it. This paper presents a methodology to compare these algorithms together. Moreover, by the way of geometric dissimilarity criteria, the algorithms are tuned up, and the best parameter values are thus proposed to the expert ophthalmologists.

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Strontium-Loaded Nanotubes of Ti–24Nb–4Zr–8Sn Alloys for Biomedical Implantation

Journal of Biomedical Nanotechnology ◽

10.1166/jbn.2021.3160 ◽

2021 ◽

Vol 17 (9) ◽

pp. 1812-1823

Author(s):

Fei Liu ◽

Xinyu Wang ◽

Shujun Li ◽

Yiheng Liao ◽

Xinxin Zhan ◽

...

Keyword(s):

Early Stage ◽

Contact Rate ◽

Hard Tissue ◽

Tissue Slices ◽

Bone Implant ◽

P Elements ◽

Low Elastic Modulus ◽

Bone Implant Contact

Ti–24Nb–4Zr–8Sn (Ti2448) alloys, with a relatively low elastic modulus and unique mechanical properties, are desirable materials for oral implantation. In the current study, a multifaceted strontium-incorporating nanotube coating was fabricated on a Ti2448 alloy (Ti2-NTSr) through anodization and hydrothermal procedures. In vitro, the Ti2-NTSr specimens demonstrated better osteogenic properties and more favorable osteoimmunomodulatory abilities. Moreover, macrophages on Ti2-NTSr specimens could improve the recruitment and osteogenic differentiation of osteoblasts. In vivo, dense clots with highly branched, thin fibrins and small pores existed on the Ti2-NTSr implant in the early stage after surgery. Analysis of the deposition of Ca and P elements, hard tissue slices and the bone-implant contact rate (BIC%) of the Ti2-NTSr implants also showed superior osseointegration. Taken together, these results demonstrate that the Ti2-NTSr coating may maximize the clinical outcomes of Ti2448 alloys for implantation applications.

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