Non-Articular Bone Surface

2020 ◽  
Author(s):  
Keyword(s):  
Bone Surface

scholarly journals Comparison of Resistive and Optical Strain Measurement for Early Fracture Detection

2020 ◽  
Vol 6 (3) ◽  
pp. 196-199
Author(s):  
Alina Carabello ◽  
Constanze Neupetsch ◽  
Michael Werner ◽  
Christian Rotsch ◽  
Welf-Guntram Drossel ◽  
...  
Keyword(s):  
Surgical Training ◽  
Error Detection ◽  
Strain Measurement ◽  
Testing Machine ◽  
Image Correlation ◽  
Strain Gauges ◽  
Measurement Technology ◽  
Bone Surface ◽  
Fracture Detection ◽  
Local Strains

AbstractTo increase learning success in surgical training, physical simulators are supplemented by measurement technology to generate and record objective feedback and error detection. An opportunity to detect fractures following hip stem implantation early can be measurement of occurring strains on bone surface. These strains can be determined while using strain gauges, digital image correlation (DIC) or photoelasticity. In this research strain gauges and DIC were compared regarding their suitability as strain measurement tools for use in physical simulators. Therefore a testing method was described to replicate the implantation of a hip stem. Testing devices modelled on a realistic prosthesis were pressed into prepared porcine femora in a two-step procedure with a material testing machine. The local strains occurring on bone surface were determined using an optical measurement system for DIC and strain gauges. The initial fractures in the tested femora are located medial-anterior in most cases (73,6%). With increasing indentation depth of the test device, the strains on bone surface increase. Comparing the local strains determined by DIC and strain gauges consistencies in curves are noticeable. Maximal determined strains before fracturing amount to 0,69% with strain gauges and 0,75% with DIC. In the range of the fracture gap, strain gradients are determined by using DIC. However the detected surfaces are of low quality caused by gaps and motion artefacts. The results show strains on bone surfaces for early fracture detection are measurable with strain gauges and DIC. DIC is assessed as less suitable compared to strain gauges. Furthermore strain gauges have greater level of integration and economic efficiency, so they are preferred the use in surgical training simulators.

scholarly journals Improvement of biohistological response of facial implant materials by tantalum surface treatment

2019 ◽  
Vol 41 (1) ◽  
Author(s):  
Mohammed Mousa Bakri ◽  
Sung Ho Lee ◽  
Jong Ho Lee
Keyword(s):  
Foreign Body ◽  
Soft Tissue ◽  
Surface Treatment ◽  
Clinical Applications ◽  
Tissue Response ◽  
Bone Surface ◽  
Tissue Thickness ◽  
Implant Materials ◽  
Soft Tissue Thickness

Abstract Background A compact passive oxide layer can grow on tantalum (Ta). It has been reported that this oxide layer can facilitate bone ingrowth in vivo though the development of bone-like apatite, which promotes hard and soft tissue adhesion. Thus, Ta surface treatment on facial implant materials may improve the tissue response, which could result in less fibrotic encapsulation and make the implant more stable on the bone surface. The purposes of this study were to verify whether surface treatment of facial implant materials using Ta can improve the biohistobiological response and to determine the possibility of potential clinical applications. Methods Two different and commonly used implant materials, silicone and expanded polytetrafluoroethylene (ePTFE), were treated via Ta ion implantation using a Ta sputtering gun. Ta-treated samples were compared with untreated samples using in vitro and in vivo evaluations. Osteoblast (MG-63) and fibroblast (NIH3T3) cell viability with the Ta-treated implant material was assessed, and the tissue response was observed by placing the implants over the rat calvarium (n = 48) for two different lengths of time. Foreign body and inflammatory reactions were observed, and soft tissue thickness between the calvarium and the implant as well as the bone response was measured. Results The treatment of facial implant materials using Ta showed a tendency toward increased fibroblast and osteoblast viability, although this result was not statistically significant. During the in vivo study, both Ta-treated and untreated implants showed similar foreign body reactions. However, the Ta-treated implant materials (silicone and ePTFE) showed a tendency toward better histological features: lower soft tissue thickness between the implant and the underlying calvarium as well as an increase in new bone activity. Conclusion Ta surface treatment using ion implantation on silicone and ePTFE facial implant materials showed the possibility of reducing soft tissue intervention between the calvarium and the implant to make the implant more stable on the bone surface. Although no statistically significant improvement was observed, Ta treatment revealed a tendency toward an improved biohistological response of silicone and ePTFE facial implants. Conclusively, tantalum treatment is beneficial and has the potential for clinical applications.

scholarly journals Regeneration in Experimental Alveolar Bone Defect Using Human Umbilical Cord Mesenchymal Stem Cells

2021 ◽  
Vol 30 ◽  
pp. 096368972097539
Author(s):  
Akiko Toyota ◽  
Rei Shinagawa ◽  
Mikiko Mano ◽  
Kazuyuki Tokioka ◽  
Naoto Suda
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Bone Formation ◽  
Cleft Lip ◽  
Human Umbilical Cord ◽  
Bone Surface ◽  
Bone Bridge ◽  
Bridge Formation ◽  
Alveolar Cleft ◽  
Umbilical Cords

Cleft lip and palate is a congenital disorder including cleft lip, and/or cleft palate, and/or alveolar cleft, with high incidence.The alveolar cleft causes morphological and functional abnormalities. To obtain bone bridge formation and continuous structure between alveolar clefts, surgical interventions are performed from infancy to childhood. However, desirable bone bridge formation is not obtained in many cases. Regenerative medicine using mesenchymal stem cells (MSCs) is expected to be a useful strategy to obtain sufficient bone bridge formation between alveolar clefts. In this study, we examined the effect of human umbilical cord-derived MSCs by transplantation into a rat experimental alveolar cleft model. Human umbilical cords were digested enzymatically and the isolated cells were collected (UC-EZ cells). Next, CD146-positive cells were enriched from UC-EZ cells by magnetic-activated cell sorting (UC-MACS cells). UC-EZ and UC-MACS cells showed MSC gene/protein expression, in vitro. Both cells had multipotency and could differentiate to osteogenic, chondrogenic, and adipogenic lineages under the differentiation-inducing media. However, UC-EZ cells lacked Sox2 expression and showed the lower ratio of MSCs than UC-MACS cells. Thus, UC-MACS cells were transplanted with hydroxyapatite and collagen (HA + Col) into alveolar cleft model to evaluate bone formation in vivo. The results of micro computed tomography and histological staining showed that UC-MACS cells with HA + Col induced more abundant bone formation between the experimental alveolar clefts than HA + Col implantation only. Cells immunopositive for osteopontin were accumulated along the bone surface and some of them were embedded in the bone. Cells immunopositive for human-specific mitochondria were aligned along the newly formed bone surface and in the new bone, suggesting that UC-MACS cells contributed to the bone bridge formation between alveolar clefts. These findings indicate that human umbilical cords are reliable bioresource and UC-MACS cells are useful for the alveolar cleft regeneration.

scholarly journals Conditional Deletion of Prolyl Hydroxylase Domain-Containing Protein 2 (Phd2) Gene Reveals Its Essential Role in Chondrocyte Function and Endochondral Bone Formation

Endocrinology ◽  
2016 ◽  
Vol 157 (1) ◽  
pp. 127-140 ◽  
Author(s):  
Shaohong Cheng ◽  
Weirong Xing ◽  
Sheila Pourteymoor ◽  
Jan Schulte ◽  
Subburaman Mohan
Keyword(s):  
Bone Formation ◽  
Growth Plate ◽  
Prolyl Hydroxylase ◽  
Conditional Knockout ◽  
Hypertrophic Chondrocytes ◽  
Endochondral Bone Formation ◽  
Bone Surface ◽  
Endochondral Bone ◽  
Prolyl Hydroxylase Domain

Abstract The hypoxic growth plate cartilage requires hypoxia-inducible factor (HIF)-mediated pathways to maintain chondrocyte survival and differentiation. HIF proteins are tightly regulated by prolyl hydroxylase domain-containing protein 2 (Phd2)-mediated proteosomal degradation. We conditionally disrupted the Phd2 gene in chondrocytes by crossing Phd2 floxed mice with type 2 collagen-α1-Cre transgenic mice and found massive increases (>50%) in the trabecular bone mass of long bones and lumbar vertebra of the Phd2 conditional knockout (cKO) mice caused by significant increases in trabecular number and thickness and reductions in trabecular separation. Cortical thickness and tissue mineral density at the femoral middiaphysis of the cKO mice were also significantly increased. Dynamic histomorphometric analyses revealed increased longitudinal length and osteoid surface per bone surface in the primary spongiosa of the cKO mice, suggesting elevated conversion rate from hypertrophic chondrocytes to mineralized bone matrix as well as increased bone formation in the primary spongiosa. In the secondary spongiosa, bone formation measured by mineralizing surface per bone surface and mineral apposition rate were not changed, but resorption was slightly reduced. Increases in the mRNA levels of SRY (sex determining region Y)-box 9, osterix (Osx), type 2 collagen, aggrecan, alkaline phosphatase, bone sialoprotein, vascular endothelial growth factor, erythropoietin, and glycolytic enzymes in the growth plate of cKO mice were detected by quantitative RT-PCR. Immunohistochemistry revealed an increased HIF-1α protein level in the hypertrophic chondrocytes of cKO mice. Infection of chondrocytes isolated from Phd2 floxed mice with adenoviral Cre resulted in similar gene expression patterns as observed in the cKO growth plate chondrocytes. Our findings indicate that Phd2 suppresses endochondral bone formation, in part, via HIF-dependent mechanisms in mice.

Machine learning, bootstrapping, null models, and why we are still not 100% sure which bone surface modifications were made by crocodiles

2021 ◽  
pp. 103071
Author(s):  
Shannon P. McPherron ◽  
Will Archer ◽  
Erik R. Otárola-Castillo ◽  
Melissa G. Torquato ◽  
Trevor L. Keevil
Keyword(s):  
Machine Learning ◽  
Surface Modifications ◽  
Null Models ◽  
Bone Surface

Resorption of bone by isolated rabbit osteoclasts

1984 ◽  
Vol 66 (1) ◽  
pp. 383-399
Author(s):  
T.J. Chambers ◽  
P.A. Revell ◽  
K. Fuller ◽  
N.A. Athanasou
Keyword(s):  
Indirect Effects ◽  
Cytochalasin B ◽  
Model System ◽  
Long Bones ◽  
Direct And Indirect Effects ◽  
Bone Surface ◽  
Surface Appearance ◽  
Complex Morphology ◽  
Resorptive Activity ◽  
Circular Outline

A carborundum wheel was used to prepare slices of cortical bone that demonstrate a predictable surface appearance in the scanning electron microscope. Osteoclasts were mechanically disaggregated from neonatal rabbit long bones and settled onto these slices. After 24h in culture osteoclasts were associated with areas of excavation in the bone surface. These excavated areas typically showed a well-defined outline and a distinctive fibrillar base, which resembled the pattern of collagen fibrils in bone. The majority of such concavities were of approximately circular outline and of smaller diameter than the associated osteoclast, but other excavations were elongated or of complex morphology, and may have been produced by osteoclasts that were resorbing bone while they migrated. Irregular concavities tended to be more shallow but to occupy a greater area of the bone surface than circular concavities. Roughening of the bone surface without detectable excavation was also seen adjacent to osteoclasts. Calcitonin and cytochalasin B, which inhibit osteoclastic motility, also inhibited bone resorptive activity by these cells. The techniques described in this paper represent a model system with which to assess the direct and indirect effects of hormones, cells and substrate composition on the induction, stimulation and inhibition of osteoclastic bone resorption and to investigate the mechanisms by which cells degrade extracellular matrices.

The trajectory of bone surface modification studies in paleoanthropology and a new Bayesian solution to the identification controversy

2017 ◽  
Vol 110 ◽  
pp. 69-81 ◽  
Author(s):  
Jacob A. Harris ◽  
Curtis W. Marean ◽  
Kiona Ogle ◽  
Jessica Thompson
Keyword(s):  
Surface Modification ◽  
Bone Surface

Prediction of Fluid Flow in Artificial Cancellous Bone

2014 ◽  
Vol 695 ◽  
pp. 393-397
Author(s):  
Elsa Syuhada Abdull Yamin ◽  
Nor Azwadi Che Sidik
Keyword(s):  
Fluid Flow ◽  
Pore Size ◽  
Surface Area ◽  
Pore Diameter ◽  
Bone Surface ◽  
Flow Conditions ◽  
Morphological Aspects ◽  
Flow Through ◽  
Structure Result ◽  
Dynamics Method

The permeability of the blood in the artificial cancellous are affected by certain morphological aspects that include pore diameter, pore size, porosity and the bone surface area. In this study, computational fluid dynamics method is used to study the fluid flow through the cancellous structure. Result of the present work show that geometries with the same porosity and overall volume can have different permeability due to the differences in bone surface area. The hexahedron geometry has the highest permeability under stimulated blood flow conditions, where the cylindrical geometry has the lowest. Linear relationship is found between permeability and the two physical properties, bone surface area and the pore size.

Sign in / Sign up

Export Citation Format

Share Document