The Micromechanics Versus the Macromechanics of Cortical Bone—A Comprehensive Presentation

1988 ◽  
Vol 110 (4) ◽  
pp. 357-363 ◽  
Author(s):  
A. Ascenzi
Keyword(s):  
Mechanical Properties ◽  
Cortical Bone ◽  
Biomechanical Properties ◽  
Fiber Bundles ◽  
Relative Distribution ◽  
Longitudinal Course ◽  
Macroscopic Level ◽  
Pathological Conditions

Secondary cortical bone is a complicated patchwork of structures which can be viewed as a hierarchy of four different orders. As far as the biomechanical properties of cortical bone are concerned, the lamella is the most important of the four. The relative distribution of longitudinal lamellae (whose fiber bundles and crystallites have a longitudinal course and withstand loading by tension) with respect to transverse lamellae (whose fiber bundles and crystallites have a transverse course and withstand loading by compression) governs the mechanical properties of bone at macroscopic level both in normal and pathological conditions.

scholarly journals Biomechanical Properties of Bone and Mucosa for Design and Application of Dental Implants

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2845
Author(s):  
Michael Gasik ◽  
France Lambert ◽  
Miljana Bacevic
Keyword(s):  
Mechanical Properties ◽  
Dental Implants ◽  
Soft Tissues ◽  
Biomechanical Properties ◽  
Stress And Strain ◽  
Pathological Conditions ◽  
Strain Components ◽  
Mechanical Factors ◽  
Movement And Deformation ◽  
Mechanical Movement

Dental implants’ success comprises their proper stability and adherence to different oral tissues (integration). The implant is exposed to different mechanical stresses from swallowing, mastication and parafunctions for a normal tooth, leading to the simultaneous mechanical movement and deformation of the whole structure. The knowledge of the mechanical properties of the bone and gingival tissues in normal and pathological conditions is very important for the successful conception of dental implants and for clinical practice to access and prevent potential failures and complications originating from incorrect mechanical factors’ combinations. The challenge is that many reported biomechanical properties of these tissues are substantially scattered. This study carries out a critical analysis of known data on mechanical properties of bone and oral soft tissues, suggests more convenient computation methods incorporating invariant parameters and non-linearity with tissues anisotropy, and applies a consistent use of these properties for in silico design and the application of dental implants. Results show the advantages of this approach in analysis and visualization of stress and strain components with potential translation to dental implantology.

Biomechanical Properties of the Stifle Joint Lateral Collateral Ligament in Dogs

1992 ◽  
Vol 05 (04) ◽  
pp. 158-162 ◽  
Author(s):  
D. Blackketter ◽  
J Harari ◽  
J. Dupuis
Keyword(s):  
Mechanical Properties ◽  
Cruciate Ligament ◽  
Lateral Collateral Ligament ◽  
Biomechanical Properties ◽  
Fibular Head ◽  
Joint Stability ◽  
Collateral Ligament ◽  
Cranial Cruciate Ligament ◽  
Stifle Joint

Bone/lateral collateral ligament/bone preparations were tested and structural mechanical properties compared to properties of cranial cruciate ligament in 15 dogs. The lateral collateral ligament has sufficient stiffness to provide stifle joint stability and strength to resist acute overload following fibular head transposition.

Research on Anisotropic Fracture Mechanical Behavior of Cortical Bone with Combined Method of Fractal and Gray Level Co-Occurrence Matrix

2021 ◽  
Vol 11 (1) ◽  
pp. 67-75
Author(s):  
Dagang Yin ◽  
Bin Chen ◽  
Huifen Zhou
Keyword(s):  
Mechanical Properties ◽  
Fracture Surface ◽  
Cortical Bone ◽  
Fracture Mechanisms ◽  
Gray Level ◽  
Combined Method ◽  
Characteristic Parameters ◽  
Fracture Surfaces ◽  
Anisotropic Fracture ◽  
Occurrence Matrix

The irregular fracture surface of cortical bone, which is caused by complex multilevel micro-nanostructure, reflects the mechanical properties and fracture mechanisms. It is of great significance to characterize some characteristic parameters from the fracture surfaces of bone. In this research, anisotropic fracture mechanical properties of bovine femoral cortical bone along transverse, longitudinal and radial direction are firstly obtained by three-point bend experiment. Then the fracture routes and fracture surfaces are observed by scanning electron microscope. The observation shows that the formed fracture surfaces, which are caused by different crack routes, are extremely rough and have complex textures. Lastly, the combined method of fractal and gray level co-occurrence matrix are adopted to describe the morphology of fracture surface of cortical bone objectively and quantitatively. It is shown that the fracture surface of cortical bone has obvious fractal characteristics and four statistical texture feature parameters (contrast,angular second moment, correlation and entropy) of GLCM of fracture surfaces can describe a certain fracture texture character. The relationship between the characteristic parameters and macroscopic mechanical properties are established. The quantitative analysis and automatic class identification for the fracture surfaces of cortical bone can be achieved.

Tissue level mechanical properties of cortical bone in skeletally immature and mature dogs

2009 ◽  
Vol 22 (03) ◽  
pp. 210-215 ◽  
Author(s):  
C.A. Phillips ◽  
S.A. Fernandez ◽  
Y. Li ◽  
S.S. Huja
Keyword(s):  
Mechanical Properties ◽  
Cortical Bone ◽  
Tissue Level ◽  
Mechanical Tests ◽  
Indentation Modulus ◽  
Skeletally Immature ◽  
Beagle Dogs ◽  
Cross Sectional ◽  
Specimen Holder ◽  
Immature Group

Summary Objectives: The purpose of this study was to quantify the tissue level mechanical properties of cortical bone of skeletally immature (~five-month-old) Beagle dogs and compare them to data from mature dogs measured in a previous study. Methods: Eight femoral cross sectional specimens (two bone sections / dog) were obtained from four skeletally immature dogs. A pair of calcein bone labels were administered intravenously to the dogs to mark sites of active mineralization prior to euthanasia. Prepared bone specimens were placed in a nanoindenter specimen holder and the previously identified calcein labelled osteons were located. Labelled (n = 128) and neighbouring unlabelled (n = 127) osteons in skeletally immature femurs were examined by instrumented indentation testing. Indents were made to a depth of 500 nm at a loading rate of 10 nm/s. Indentation modulus (IM) and hardness (H) were obtained. Results: The overall IM of the cortical bone in the skeletally mature groups was significantly greater than in the immature group (p = 0.0011), however overall H was not significantly different. The differences between the groups in IM were significant for the unlabelled osteons (p = 0.001), but not for the labelled osteons (p = 0.56). Conclusion: There are differences in the IM of unlabelled osteons in skeletally immature and mature groups of Beagle dogs. In contrast to whole bone mechanical tests, where there are obvious differences between growing and mature bones, there are only small differences in the micro-mechanical properties.

Mechanical Anisotropy of Individual Osteons in Bone Tissue at High Spatial Resolutions

2009 ◽  
Author(s):  
Davide Carnelli ◽  
Haimin Yao ◽  
Ming Dao ◽  
Pasquale Vena ◽  
Roberto Contro ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cortical Bone ◽  
Mechanical Anisotropy ◽  
Haversian Canal ◽  
Maximum Penetration ◽  
Fundamental Units ◽  
Anisotropy Of Mechanical Properties ◽  
Penetration Depths ◽  
Secondary Osteons ◽  
Mineralized Collagen

Secondary osteons, the fundamental units of cortical bone, consist of cylindrical lamellar composites composed of mineralized collagen fibrils. Due to its lamellar structure, a multiscale knowledge of the mechanical properties of cortical bone is required to understand the biomechanical function of the tissue. In this light, nanoindentation tests were performed along the axial and transverse directions following a radial path from the Haversian canal to the osteonal edges. Different length scales are explored by means of indentations at different maximum penetration depths. Indentation moduli and hardness data were then interpreted in the context of the known microstructure. Results suggest that secondary osteons hierarchical structure is responsible for an observed length scale effect, homogenization phenomena and anisotropy of mechanical properties.

scholarly journals Longitudinal variation in mechanical competence of bone along the avian humerus.

1995 ◽  
Vol 198 (1) ◽  
pp. 209-212
Author(s):  
R H Bonser
Keyword(s):  
Mechanical Properties ◽  
Trabecular Bone ◽  
Cortical Bone ◽  
Vickers Microhardness ◽  
Bird Species ◽  
Longitudinal Variation ◽  
The Mean ◽  
Compressive Tests

Vickers microhardness tests were used to gauge the mechanical "competence" (ability to resist bending and failure) of cortical and trabecular bone along the humeri of three bird species. Hardness was greatest at the mid-length portion of the shaft. The mean hardness of trabeculae, where present, was between 78.7 and 90.9% of that of the adjacent cortical bone. The possible causes of this are briefly discussed. Microhardness tests offer the opportunity to gauge differences in mechanical properties over small distances and might usefully be applied to test the homogeneity of mechanical properties within specimens for tensile or compressive tests.

Mechanical Properties and Related Histological Alterations of Engineered Tendons In Vivo

2005 ◽  
Vol 288-289 ◽  
pp. 11-14 ◽  
Author(s):  
Ting Wu Qin ◽  
Shujiang Zhang ◽  
Zhi Ming Yang ◽  
Xiang Tao Mo ◽  
Xiu Qun Li
Keyword(s):  
Mechanical Properties ◽  
Collagen Synthesis ◽  
Biomechanical Properties ◽  
Biomechanical Test ◽  
Histological Alterations ◽  
Normal Tendon ◽  
Tendon Cells ◽  
Biomechanical Stimulation

The purpose of this research is to find out the interaction between histological alterations and mechanical properties of engineered tendon implanted in situ. Defects of 0.5cm-1.0cm were made at deep flexor tendons by surgical procedure. Engineered tendons using degradable scaffolds polyglytic acid (PGA) mesh and tendon cells were implanted to repair the defects. Chickens were killed respectively at 2 weeks, 4 weeks, 6 weeks, and 8 weeks after surgery. The implants were taken out for histological examination, biomechanical test, and collagen synthesis assay. The results showed that after surgery the PGA scaffolds degraded fast and took precedence of collagen synthesis. There were not enough amount and maturation of the collagen fibers of the new tendon at 2-8 weeks after surgery. The biomechanical properties of new tendons were less than those of the normal tendon. Therefore, it is necessary to construct engineered tendons with better degradation rate of scaffolds and suitable biomechanical stimulation so that more collagen synthesis and better biomechanical properties of new tendons can be developed early after implantation.

Time dependence analysis of mechanical properties of cortical bone

1980 ◽  
Vol 13 (9) ◽  
pp. 796
Author(s):  
J. Victoria ◽  
A. Colino ◽  
C. Hernandez-Ros ◽  
A. Victoria
Keyword(s):  
Mechanical Properties ◽  
Time Dependence ◽  
Cortical Bone ◽  
Dependence Analysis
Sign in / Sign up

Export Citation Format

Share Document