Anatomical variations in cortical bone surface permeability: Tibia versus femur

ABSTRACTObjectives: Non-homogeneous force distribution along the miniplates and the screws is an unsolved question for skeletal anchorage in orthodontics. To overcome this issue, a miniplate structure was designed featuring spikes placed on the surface facing the cortical bone. The aim of this study was to examine and compare the force distribution of the newly designed plate-screw systems with the conventional one.Methods: A model of bone surface with 1.5 mm cortical thickness, along with the two newly designed miniplates and a standard miniplate-screw were simulated on the three-dimensional model. 200 g experimental force was applied to the tip of the miniplates and the consequential effects on the screws and cortical bone was evaluated using three-dimensional finite element method.Results: As a result of this finite element study, remarkably lower stresses were observed on the screws and the cortical bone around the screws with the newly designed miniplate when compared with the conventional one.Conclusion: The newly designed miniplate that has spikes was found effective in reducing the stress on and around the screws and the force was distributed more equivalently. (Eur J Dent 2012;6:9-15)

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Pattern of Uptake of Americium-241 by the Rat Skeleton and its Subsequent Redistribution and Retention: Implications for Human Dosimetry and Toxicology

Human Toxicology ◽

10.1177/096032718300200109 ◽

1983 ◽

Vol 2 (1) ◽

pp. 101-120 ◽

Cited By ~ 17

Author(s):

N.D. Priest ◽

G. Howells ◽

D. Green ◽

J.W. Haines

Keyword(s):

Bone Marrow ◽

Bone Resorption ◽

Cortical Bone ◽

Female Rat ◽

Half Time ◽

Bone Surface ◽

Similar Model ◽

Phagocytic Cells ◽

Biological Half Time

The distribution and retention of intravenously injected 241Am in the skeleton of the female rat has been investigated using autoradiographic and radiochemical techniques. The studies were designed to assess the dosimetric and toxicologic implications of an 241Am intake by man. They showed that in the rat approximately one third of the intravenously injected 241Am was deposited in the skeleton where it appeared to be retained with a long biological half-time. The studies also showed: 1241Am is initially deposited onto all types of bone surface including endosteal surfaces, periosteal surfaces and those of the vascular canals within cortical bone, but seems to be preferentially deposited onto those that are resorbing, 2 Bone accretion results in the burial of surface deposits of 241Am, 3 Bone resorption causes the removal of 241 Am from surfaces, 4 Resorbed 241Am is retained by phagocytic cells (probably macrophages) in the bone marrow, 5 The transfer of 241Am from the phagocytic cells in the marrow to adjacent bone surfaces seems to occur, (local recycling). 6 The possibility that some of the 241Am removed from the bone surfaces enters the blood and is redeposited in bone, (systemic recycling) cannot be dismissed These results show that 241Am deposition and redistribution in bone shares many characteristics with other 'bone surface-seeking radionuclides' typified by 239Pu. Consequently, it is suggested that a similar model to that used to calculate annual limits of intake for 239Pu in man would be suitable for the calculation of corresponding values for the 241Am isotopes.

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Direct measurement of tibial cortical bone surface area

Clinical Anatomy ◽

10.1002/ca.20994 ◽

2010 ◽

Vol 23 (6) ◽

pp. 720-725

Author(s):

E. Cattrysse ◽

A. Scafoglieri ◽

O. Louis ◽

J. De Mey ◽

J.P. Clarys

Keyword(s):

Cortical Bone ◽

Surface Area ◽

Direct Measurement ◽

Bone Surface ◽

Tibial Cortical Bone

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Comparative Evaluation of Cortical Bone Anatomy of Mandibular Buccal Shelf for Mini Implant Placement in Different Facial Divergence: A Cone Beam Computed Tomography Study

The Journal of Indian Orthodontic Society ◽

10.1177/0301574220932265 ◽

2020 ◽

Vol 54 (4) ◽

pp. 325-331

Author(s):

Kalyani Trivedi ◽

Bharvi K Jani ◽

Sagar Hirani ◽

Mansi V Radia

Keyword(s):

Computed Tomography ◽

Cortical Bone ◽

Cone Beam Computed Tomography ◽

Cone Beam ◽

Bone Surface ◽

Bone Thickness ◽

Second Molar ◽

Cortical Bone Thickness ◽

Implant Placement ◽

Alveolar Crest

Aim: The purpose of this study was to use measurements from cone beam computed tomography scans to quantify the cortical bone thickness of mandibular buccal shelf region and preferable site for buccal shelf implant placement in 10 hyperdivergent and 10 hypodivergent patients. Method: 20 cone beam computed tomographies were equally divided based on divergence. 6 sites were examined: mesial of first molar (6M), middle of first molar (6Mi), interdental between the first and second molar (Id), mesial of second molar (7M), middle of second molar (7Mi), and distal of second molar (7D). The study quantified the mandibular buccal shelf relative to its angle of slope, the cortical bone thickness measured perpendicular to the bone surface, the amount of cortical bone 30° angle to the bone surface. The cortical bone thickness was measured perpendicular and at a 30° angle at 3, 5, and 7 mm from the alveolar crest. Result: Significant change is seen at the buccal shelf slope at 6M ( P = .001) and further increase in this angle till 7D ( P = .003). Mean amount of cortical bone for hyperdivergent group at 7D is 4.77 ± 0.68 mm and for hypodivergent group is 3.86 ± 0.70 mm. Statistically significant differences were noted at insertion site at 90° and 30° for both groups at 3, 5, and 7 mm from the alveolar crest. Conclusion: Preferable site for buccal shelf implant placement is distal to the mandibular second molar. The maximum amount of cortical bone is found distal to the second molar 7 mm vertically from alveolar crest when the buccal shelf implant is placed at 30° angulation for hyperdivergent group.

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Tomography-Based Quantification of Regional Differences in Cortical Bone Surface Remodeling and Mechano-Response

Calcified Tissue International ◽

10.1007/s00223-016-0217-4 ◽

2016 ◽

Vol 100 (3) ◽

pp. 255-270 ◽

Cited By ~ 21

Author(s):

Annette I. Birkhold ◽

Hajar Razi ◽

Georg N. Duda ◽

Sara Checa ◽

Bettina M. Willie

Keyword(s):

Cortical Bone ◽

Regional Differences ◽

Bone Surface ◽

Surface Remodeling

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MACHINING OF CORTICAL BONE: SURFACE TEXTURE, SURFACE INTEGRITY AND CUTTING FORCES

Machining Science and Technology ◽

10.1080/10910340801890961 ◽

2008 ◽

Vol 12 (1) ◽

pp. 100-118 ◽

Cited By ~ 32

Author(s):

C. Yeager ◽

A. Nazari ◽

D. Arola

Keyword(s):

Cortical Bone ◽

Surface Integrity ◽

Surface Texture ◽

Cutting Forces ◽

Bone Surface ◽

Texture Surface

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EXPLORING CORTICAL BONE DENSITY THROUGH THE ULTRASOUND INTEGRATED REFLECTION COEFFICIENT

Acta Ortopédica Brasileira ◽

10.1590/1413-785220182604177202 ◽

2018 ◽

Vol 26 (4) ◽

pp. 255-259

Author(s):

Daniel Patterson Matusin ◽

Aldo José Fontes-Pereira ◽

Paulo Tadeu Cardozo Ribeiro Rosa ◽

Thiago Barboza ◽

Sergio Augusto Lopes de Souza ◽

...

Keyword(s):

Computed Tomography ◽

Bone Density ◽

Reflection Coefficient ◽

Cortical Bone ◽

Quantitative Computed Tomography ◽

Density Variation ◽

Bone Surface ◽

Weak Correlation ◽

Level Of Evidence ◽

The Relationship

ABSTRACT Objective: This work evaluates the relationship between ultrasonic reflection and bone density from fourteen cylindrical bovine cortical bone samples (3.0-cm thick). Methods: Twenty US reflection signals per sample were acquired along the bone surface (2.0-mm step). The Integrated Reflection Coefficient (IRC) from each signal was compared to Quantitative Computed Tomography (QCT). Results: Seven IRC and QCT curves presented Pearson's Correlation R-values above 0.5. For weak correlation curves, QCT and IRC showed similar trends in several segments. Conclusion: IRC was sensitive to bone density variation. Level of Evidence: Experimental Study, Investigating a Diagnostic Test.

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Atomic Force Microscopy Characterization of the External Cortical Bone Surface in Young and Elderly Women: Potential Nanostructural Traces of Periosteal Bone Apposition During Aging

Microscopy and Microanalysis ◽

10.1017/s1431927613001761 ◽

2013 ◽

Vol 19 (5) ◽

pp. 1341-1349 ◽

Cited By ~ 8

Author(s):

Petar Milovanovic ◽

Marija Djuric ◽

Olivera Neskovic ◽

Danijela Djonic ◽

Jelena Potocnik ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Cortical Bone ◽

Elderly Women ◽

Mineral Particle ◽

Bone Surface ◽

Bone Apposition ◽

Force Microscopy ◽

Atomic Force ◽

Age Related

AbstractOn the basis of the suggestion that bone nanostructure bears “tissue age” information and may reflect surface deposition/modification processes, we performed nanoscale characterization of the external cortical bone surface at the femoral neck in women using atomic force microscopy (AFM). The specific aims were to assess age-related differences in bone nanostructure and explore the existence of nanostructural traces of potential bone apposition at this surface. Our findings revealed that the external cortical surface represents a continuous phase composed of densely packed mineral grains. Although the grains varied in size and shape, there was a domination of small grains indicative of freshly deposited bone (mean grain size: young, 35 nm; old, 37 nm;p> 0.05). Advanced quantitative analysis of surface morphological patterns revealed comparable roughness and complexity of the surface, suggesting a similar rate of mineral particle deposition at the surface in both groups. Calcium/phosphorus ratio, a measure of bone tissue age, was within the same range in both groups. In summary, our AFM analyses showed consistent nanostructural and compositional bone features, suggesting existence of new bone at the periosteal bone surface in both young and elderly women. Considering observed age-related increase in the neck diameter, AFM findings may support the theory of continuous bone apposition at the periosteal surface.

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The Effect of the Supplementation of a Diet Low in Calcium and Phosphorus with Either Sheep Milk or Cow Milk on the Physical and Mechanical Characteristics of Bone using A Rat Model

Foods ◽

10.3390/foods9081070 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1070

Author(s):

Keegan Burrow ◽

Wayne Young ◽

Niels Hammer ◽

Sarah Safavi ◽

Mario Scholze ◽

...

Keyword(s):

Trabecular Bone ◽

Cortical Bone ◽

Rat Model ◽

Inductively Coupled Plasma ◽

Volume Ratio ◽

Bone Volume ◽

Cow Milk ◽

Bone Surface ◽

Sheep Milk ◽

Calcium And Phosphorus

This study assessed the effect of cow milk (CM) and sheep milk (SM) consumption on the micro-structure, mechanical function, and mineral composition of rat femora in a male weanling rat model. Male weanling rats were fed a basal diet with a 50% reduction in calcium and phosphorus content (low Ca/P-diet) supplemented with either SM or CM. Rats were fed for 28 days, after which the femora were harvested and stored. The femora were analyzed by μ-CT, three-point bending, and inductively coupled plasma–mass spectrometry (ICP-MS). The addition of either milk to the low Ca/P-diet significantly increased (p < 0.05) trabecular bone volume, trabecular bone surface density, trabecular number, cortical bone volume, and maximum force, when compared to rats that consumed only the low Ca/P-diet. The consumption of either milk resulted in a significant decrease (p < 0.05) in trabecular pattern factor, and cortical bone surface to volume ratio when compared to rats that consumed only the low Ca/P-diet. The results were achieved with a lower consumption of SM compared to that of CM (p < 0.05). This work indicates that SM and CM can help overcome the effects on bone of a restriction in calcium and phosphorus intake.

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A 3-dimensional finite element analysis to evaluate the impact of force direction, insertion angle, and cortical bone thickness on mini-screw and its surrounding bone

Journal of Dental Research Dental Clinics Dental Prospects ◽

10.34172/joddd.2021.043 ◽

2021 ◽

Vol 15 (4) ◽

pp. 262-268

Author(s):

Omar Nazal Auwer ◽

Marwa Sameh Shamaa ◽

Shaza Mohammad Hammad

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Cortical Bone ◽

Horizontal Force ◽

Bone Surface ◽

Element Analysis ◽

Screw Insertion ◽

Force Direction ◽

The Impact ◽

Surrounding Bone

Background. The present study aimed to assess the stress and strain distribution on mini-screws and the surrounding bone in cases of different cortical bone thicknesses (CBTs), mini-screw insertion angles, and force directions using finite element analysis (FEA). Methods. Inventor professional version 8 software was used to construct 24 three-dimensional assemblies of mini-screws inserted with different insertion angles (30º, 60º, and 90º) in alveolar bone blocks with different CBTs (0.5, 1, 1.5, and 2 mm). The models simulated mini-screws inserted in bones with different CBTs and different insertion angles. A 2-N load was applied in two directions to mini-screw heads. The resultant stresses of the applied load were collected from the output of the ANSYS program. Results. The results indicated that force direction affected bone strains as the horizontal force generated more strains on cortical bone than the oblique one. Force applied to 60º inserted mini-screws generated much more strains on cortical bone than 90º and 30º inserted mini-screws. In a 60º inserted mini-screw, the horizontal force generated about 45% more strains on cortical bone than the oblique one. The exerted microstrain on bone decreased as CBT increased. Conclusion. It can be concluded that inserting mini-screws at 60º to the bone surface should be avoided as it generates much more strains on cortical bone than 90º and 30º, especially when a force parallel to the bone surface is applied.

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