Статті в журналах: "Bone point"

1

Beek, Maarten, Carolyn F. Small, Randy E. Ellis, Richard W. Sellens, and David R. Pichora. "Bone Alignment Using the Iterative Closest Point Algorithm." Journal of Applied Biomechanics 26, no. 4 (November 2010): 526–30. http://dx.doi.org/10.1123/jab.26.4.526.

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Computer assisted surgical interventions and research in joint kinematics rely heavily on the accurate registration of three-dimensional bone surface models reconstructed from various imaging technologies. Anomalous results were seen in a kinematic study of carpal bones using a principal axes alignment approach for the registration. The study was repeated using an iterative closest point algorithm, which is more accurate, but also more demanding to apply. The principal axes method showed errors between 0.35 mm and 0.49 mm for the scaphoid, and between 0.40 mm and 1.22 mm for the pisiform. The iterative closest point method produced errors of less than 0.4 mm. These results show that while the principal axes method approached the accuracy of the iterative closest point algorithm in asymmetrical bones, there were more pronounced errors in bones with some symmetry. Principal axes registration for carpal bones should be avoided.

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Basirom, Izzawati, Mohd Afendi Rojan, Mohd Shukry Abdul Majid, Nor Alia Md Zain, and Mohd Yazid Bajuri. "Prediction of stress shielding around implant screws induced by three-point and four-point bending." Malaysian Journal of Fundamental and Applied Sciences 15, no. 4 (August 25, 2019): 548–54. http://dx.doi.org/10.11113/mjfas.v15n4.1049.

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Implant screws failure commonly occurs due to the load that constantly generated by the patient’s body to the fracture area. Bending load is often encountered in femur bone due to lateral impact which affected the bone and also the implants installed. Consequently, the load will lead to the failure of implants that can cause loosening or tightening of implants. Henceforth, in this manner, it is significant to study the bending behavior of bone implant in femur bone. The aim of this study was to analyze the stress shielding of bone implant on the internal fixator. 3D technique is able to show the overall deformation and stress distribution. The lower the biomechanical compatibility, the lower the STP value obtained. In addition, the variation of elastic modulus (E) of the screws materials, 200GPa (Stainless Steel) and 113.8GPa (Titanium) resulted in the increase of the total stress transferred (STP) between screw and bone interface. In this work, strain energy density (SED) was determined as a good indicator of stress shielding.

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3

Skic, Anna, Iwona Puzio, Grzegorz Tymicki, Paweł Kołodziej, Marta Pawłowska-Olszewska, Kamil Skic, Karolina Beer-Lech, Marek Bieńko, and Krzysztof Gołacki. "Effect of Nesfatin-1 on Rat Humerus Mechanical Properties under Quasi-Static and Impact Loading Conditions." Materials 15, no. 1 (January 3, 2022): 333. http://dx.doi.org/10.3390/ma15010333.

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The investigations on the response of bone tissue under different loading conditions are important from clinical and engineering points of view. In this paper, the influence of nesfatin-1 administration on rat humerus mechanical properties was analyzed. The classical three-point bending and impact tests were carried out for three rat bone groups: control (SHO), the humerus of animals under the conditions of established osteopenia (OVX), and bones of rats receiving nesfatin-1 after ovariectomy (NES). The experiments proved that the bone strength parameters measured under various mechanical loading conditions increased after the nesfatin-1 administration. The OVX bones were most susceptible to deformation and had the smallest fracture toughness. The SEM images of humerus fracture surface in this group showed that ovariectomized rats had a much looser bone structure compared to the SHO and NES females. Loosening of the bone structure was also confirmed by the densitometric and qualitative EDS analysis, showing a decrease in the OVX bones’ mineral content. The samples of the NES group were characterized by the largest values of maximum force obtained under both quasi-static and impact conditions. The energies absorbed during the impact and the critical energy for fracture (from the three-point bending test) were similar for the SHO and NES groups. Statistically significant differences were observed between the mean Fi max values of all analyzed sample groups. The obtained results suggest that the impact test was more sensitive than the classical quasi-static three-point bending one. Hence, Fi max could be used as a parameter to predict bone fracture toughness.

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4

Claassen, Cheryl. "Abundant Gifts of Stone and Bone." Midcontinental Journal of Archaeology 41, no. 3 (October 1, 2016): 274–94. http://dx.doi.org/10.2307/26599942.

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Abstract An abundance of points, flakes, bones, shells, and bodies is considered sufficient to raise the hypothesis that these offerings and their places constitute a type of fertility shrine. This paper documents several possible lithic and bone-offering places in eastern North America, among them Allumettes Island, Quebec; Tick Creek Cave, Missouri; James Creek, West Virginia; and Pen Point, South Carolina. Perhaps the most significant Late Archaic shrine marked by an abundance of points, deer bones, and human burials is Indian Knoll, Kentucky. The proposed fertility or increase rite practiced was that for a hunt god.

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Robbins, Lawrence H., Alec C. Campbell, George A. Brook, Michael L. Murphy, and Robert K. Hitchcock. "The Antiquity of the Bow and Arrow in the Kalahari Desert: Bone Points from White Paintings Rock Shelter, Botswana." Journal of African Archaeology 10, no. 1 (October 25, 2012): 7–20. http://dx.doi.org/10.3213/2191-5784-10211.

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This paper presents new information on the antiquity of the bow and arrow in the Kalahari. Excavations at White Paintings Shelter (WPS) uncovered bone point fragments that appear to have been parts of reversible arrowheads that could have been used with poison. We present a sequence of nine new, internally consistent OSL ages that date specific soil horizons at WPS. These dates/soil horizons are related to the bone point finds. The oldest bone points are estimated to date between 35–37 ka, while worked bone technology extends to at least 45 ka. Several engraved points are also discussed in relation to ethnographic evidence regarding decorated bone link-shafts collected in the 1970s. Additional information includes the first description of a reversible bone arrow point, made by a person who used such points with poison in his youth.

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Heller, Ugo, Robin Evrard, Benoit Lengelé, Thomas Schubert, Natacha Kadlub, and Jean Boisson. "Decellularized vascularized bone grafts as therapeutic solution for bone reconstruction: A mechanical evaluation." PLOS ONE 18, no. 1 (January 13, 2023): e0280193. http://dx.doi.org/10.1371/journal.pone.0280193.

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Introduction Large bone defects are challenging for surgeons. Available reimplanted bone substitutes can’t properly restore optimal function along and long term osteointegration of the bone graft. Bone substitute based on the perfusion-decellularization technique seem to be interesting in order to overcome these limitations. We present here an evaluation of the biomechanics of the bones thus obtained. Material and methods Two decellularization protocols were chosen for this study. One using Sodium Dodecyl Sulfate (SDS) (D1) and one using NaOH and H2O2 (D2). The decellularization was performed on porcine forearms. We then carried out compression, three-point bending, indentation and screw pull-out tests on each sample. Once these tests were completed, we compared the results obtained between the different decellularization protocols and with samples left native. Results The difference in the means was similar between the tests performed on bones decellularized with the SDS protocol and native bones for pull-out test: +1.4% (CI95% [-10.5%– 12.4%]) of mean differences when comparing Native vs D1, compression -14.9% (CI95% [-42.7%– 12.5%]), 3-point bending -5.7% (CI95% [-22.5%– 11.1%]) and indentation -10.8% (CI95% [-19.5%– 4.6%]). Bones decellularized with the NaOH protocol showed different results from those obtained with the SDS protocol or native bones during the pull-out screw +40.7% (CI95% [24.3%– 57%]) for Native vs D2 protocol and 3-point bending tests +39.2% (CI95% [13.7%– 64.6%]) for Native vs D2 protocol. The other tests, compression and indentation, gave similar results for all our samples. Conclusion Vascularized decellularized grafts seem to be an interesting means for bone reconstruction. Our study shows that the decellularization method affects the mechanical results of our specimens. Some methods seem to limit these alterations and could be used in the future for bone decellularization.

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Vaibhav, Neelam Manoj, Ramesh Amirisetty, Rajesh Nichenametla, Gonabhavi Siri Chandana, Santhi Prathyusha M, Naresh Kumar C, and B. Tanuja Reddy. "Evaluation of zygomatic bone region for placement of quad zygomatic implants using CBCT in postmenopausal women." IP International Journal of Maxillofacial Imaging 7, no. 2 (July 15, 2021): 48–53. http://dx.doi.org/10.18231/j.ijmi.2021.010.

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Insufficient height and width of the alveolar ridge at the implant site remains with inadequate bone volume following extraction in older age people especially in postmenopausal women. Postmenopausal women are susceptible to primary osteoporosis where more bone resorption than formation is seen resulting in decreased bone mass. Hence the present study aims to evaluate the zygomatic bone region for placement of quad zygomatic implants using CBCT.: A total of 120 CBCT images of female patients who were between the age group of 45 yrs to 65 yrs were taken. The zygomatic bone was evaluated for pneumatisation zones and thickness of zygomatic bone at three different regions i.e., superior, middle and inferior at nine points on zygoma bone along with bone to implant contact (BIC) region using virtual software. The largest thickness in the superior, middle and inferior regions were at Point A2(8.01+/-2.10 mm), Point B2 (7.01+/-1.62 mm), and Point C1 (6.65+/-1.64 mm), respectively. The virtually placed implants at Point A3 (15.92+/-4.16 mm) and Point B2 (12.02+/-3.62 mm) had the highest BICs. : To obtain the largest BICs, results suggested that the posterosuperior region (Point A3) and the centre of zygoma (Point B1) were the optimal places for the placement of quad zygomatic implants.

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8

Abu-Amer, Yousef, та M. Mehrdad Tondravi. "NF-κB and bone: The breaking point". Nature Medicine 3, № 11 (листопад 1997): 1189–90. http://dx.doi.org/10.1038/nm1197-1189.

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9

Zhang, Chenghao, Ling Ji, Zhihe Zhao, and Wen Liao. "Detailed Correlation between Central Incisor Movement and Alveolar Bone Resorption in Adults with Orthodontic Premolar Extraction Treatment: A Retrospective Cohort CBCT Study." Journal of Clinical Medicine 11, no. 22 (November 21, 2022): 6872. http://dx.doi.org/10.3390/jcm11226872.

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Background: This study aims to explore the detailed correlation between the movement of maxillary and mandibular central incisors and alveolar bone resorption in adults who had orthodontic premolar extraction treatment. Methods: A total of 63 adult patients (mean age, 24.41 years) who received orthodontic treatment with the extraction of four first premolars were included in this study. CBCT images were obtained before and after treatment. Three-dimensional evaluations of the movement of 252 central incisors (126 maxillary and 126 mandibular incisors) and alveolar bone changes were conducted. Four points were used to describe the incisor movement: C (cusp point), R (root apex point), M (mid-point of root neck), and L (labial cementoenamel junction point). The thickness of labial and palatal alveolar bone was assessed at the crestal, mid-root, and apical levels of incisors. The results were analyzed with Spearman’s correlation and multilinear regression. Results: Matching the measurements of central incisor movement and alveolar bone resorption, significant correlations could be observed. For maxillary central incisors, the labial alveolar bone resorption at the crestal level was correlated with the movement of Point L (r = 0.290, p < 0.05), and the labial alveolar bone resorption at the apical level was correlated with Point M (r = 0.387, p < 0.05). For mandibular central incisors, the labial alveolar bone resorption at the apical level was correlated with the movement of Point M (r = 0.493, p < 0.05) and R (r = 0.498, p < 0.01); the palatal alveolar bone resorption at the mid-root level with Point M (r = -0.170, p < 0.01); and the palatal alveolar bone resorption at the apical level with Point R (r = 0.177, p < 0.01). Conclusions: This study investigated the concrete correlations between central incisor movement and alveolar bone resorption in adults after orthodontic treatment with premolar extraction. It is potentially helpful for orthodontists to have a relatively accurate prediction of alveolar bone resorption based on the specific movements of central incisors and to reduce the risk of alveolar bone resorption by better adjusting the three-dimensional movement types of incisors.

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10

Marin, Sasa, Aleksandra Djeri, Helena Vidovic, Natasa Trtic, Adriana Arbutina, and Verica Pavlic. "Cone-beam computed tomography assessment of the buccal bone thickness in anterior maxillary and mandibular teeth." Medical review 74, no. 11-12 (2021): 362–67. http://dx.doi.org/10.2298/mpns2112362m.

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Introduction. The aim of this study was to assess the buccal bone thickness in anterior maxillary and mandibular teeth and to provide information important during immediate implant placement. Material and Methods. The study included 245 cone-beam computed tomography scans. The buccal bone thickness was measured in the sagittal plane of the maxillary and mandibular anterior teeth at five points (M1 - M5) (2 mm apart), starting 2 mm from the cementoenamel junction in the coronal to apical position along the roots. Results. The lowest mean buccal bone thickness was observed at M1 point in all teeth in both jaws while the highest mean buccal bone thickness was observed at M4 (maxilla) and M5 (mandible). An increase of the buccal bone thickness was established at every subsequent measurement point perpendicular to the long axis of the tooth (p < 0.001). The buccal bone thickness was less than 1 mm in more than 60% of all teeth in the maxilla and mandible at all measurement points. A statistically significant difference in the thickness of the buccal bone in relation to the patients? age was found at all measurement points, except at M4 point of the anterior teeth of the maxilla (p = 0.456) and mandible (p = 0.109). Conclusion. The buccal bone thickness in anterior maxillary and mandibular teeth is less than 1 mm in more than 60% at all measurement points. The buccal bone thickness tends to increase from a coronal to apical position along the roots.

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Grimm, Cindy M., Joseph J. Crisco, and David H. Laidlaw. "Fitting Manifold Surfaces to Three-Dimensional Point Clouds." Journal of Biomechanical Engineering 124, no. 1 (August 31, 2001): 136–40. http://dx.doi.org/10.1115/1.1431266.

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We present a technique for fitting a smooth, locally parameterized surface model (called the manifold surface model) to unevenly scattered data describing an anatomical structure. These data are acquired from medical imaging modalities such as CT scans or MRI. The manifold surface is useful for problems which require analyzable or parametric surfaces fitted to data acquired from surfaces of arbitrary topology (e.g., entire bones). This surface modeling work is part of a larger project to model and analyze skeletal joints, in particular the complex of small bones within the wrist and hand. To demonstrate the suitability of this model we fit to several different bones in the hand, and to the same bone from multiple people.

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Zambrano M., Lilibeth A., David Kilroy, Arun Kumar, Michael D. Gilchrist, and Aisling Ní Annaidh. "The presence of Wormian bones increases the fracture resistance of equine cranial bone." PLOS ONE 16, no. 4 (April 16, 2021): e0249451. http://dx.doi.org/10.1371/journal.pone.0249451.

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Wormian (intrasutural) bones are small, irregular bones, that are found in the cranial sutures of the skull. The occurrence of Wormian bones in human skulls has been well documented but few studies have detected the presence of such bones in domestic animals. Although some research has linked the presence of Wormian bones to bone pathology, its anatomical significance in healthy individuals is not known. To the best of our knowledge, no previous study has examined the biomechanical features of Wormian bone. This study uses microCT imaging of the parietal bone region to determine the frequency of occurrence of Wormian bones in horse skulls and, through 3-point bending tests, to calculate the mechanical differences that result from the presence of such bones. In addition, bone properties such as bone mineral density (BMD) and stiffness were measured and analysed to determine the influence of Wormian bone. Our findings on 54 specimens taken from 10 horses (ages ranging from 4 to 29 years) showed that Wormian bone was present in 70% of subjects and that its occurrence was unrelated to age or sex. 3-point bend tests revealed that the stiffness normalised by cross section area (P = 0.038) was lower in samples where Wormian bone was present. An idealised Finite Element simulation confirmed that the presence of Wormian bone reduced the maximum stress and strain, as well as their distribution throughout the sample. We consequently conclude that the presence of Wormian bones, which are confined to the calvaria, increase the compliance of the bone and reduce the likelihood of skull fracture. As all skull samples were collected from a local abattoir, ethical approval was not required for this work.

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Ching, Michael, Aaron Gee, Christopher Del Balso, Abdel Lawendy, Emil H. Schemitsch, Radovan Zdero, and David Sanders. "Biomechanical Consequences of Nail Insertion Point and Anterior Cortical Perforation for Antegrade Femoral Nailing." BioMed Research International 2020 (December 18, 2020): 1–10. http://dx.doi.org/10.1155/2020/5878607.

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This biomechanical study assessed the influence of changing antegrade cephalomedullary nail insertion point from anterior to neutral to posterior locations relative to the tip of the greater trochanter with or without anterior cortical perforation in the distal femur. Artificial osteoporotic femurs and cephalomedullary nails were used to create 5 test groups each with 8 specimens: intact femur without a nail or perforation, anterior nail insertion point without perforation, neutral nail insertion point without perforation, posterior nail insertion point without perforation, and posterior nail insertion point with perforation. Nondestructive biomechanical tests were done at 250 N in axial, coronal 3-point bending, sagittal 3-point bending, and torsional loading in order to measure overall stiffness and bone stress. The intact femur group vs. all femur/nail groups had lower stiffness in all loading modes ( p ≤ 0.018 ), as well as higher bone stress in the proximal femur ( p ≤ 0.027 ) but not in the distal femur above the perforation ( p = 0.096 ). Compared to each other, femur/nail groups only showed differences in sagittal 3-point bending stiffness for anterior and neutral vs. posterior nail insertion points without ( p ≤ 0.025 ) and with perforation ( p ≤ 0.047 ). Although it did not achieve statistical significance ( p ≥ 0.096 ), moving the nail insertion point from anterior to neutral to posterior to posterior with perforation did gradually increase bone stress by 45% (proximal femur) and 46% (distal femur). No femur or hardware failures occurred. Moving the nail insertion point and the presence of a perforation had little effect on stiffness, but the increased bone stress may be important as a predictor of fracture. Based on current bone stress results, surgeons should use anterior or neutral nail insertion points to reduce the risk of anterior cortical perforation.

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De Vita, Elena, Martina Zaltieri, Francesca De Tommasi, Carlo Massaroni, Eliodoro Faiella, Bruno Beomonte Zobel, Agostino Iadicicco, Emiliano Schena, Rosario Francesco Grasso, and Stefania Campopiano. "Multipoint Temperature Monitoring of Microwave Thermal Ablation in Bones through Fiber Bragg Grating Sensor Arrays." Sensors 20, no. 11 (June 4, 2020): 3200. http://dx.doi.org/10.3390/s20113200.

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Bones are a frequent site of metastases that cause intolerable cancer-related pain in 90% of patients, making their quality of life poor. In this scenario, being able to treat bone oncology patients by means of minimally invasive techniques can be crucial to avoid surgery-related risks and decrease hospitalization times. The use of microwave ablation (MWA) is gaining broad clinical acceptance to treat bone tumors. It is worth investigating temperature variations in bone tissue undergoing MWA because the clinical outcomes can be inferred from this parameter. Several feasibility studies have been performed, but an experimental analysis of the temperature trends reached into the bone during the MWA has not yet been assessed. In this work, a multi-point temperature study along the bone structure during such treatment is presented. The study has been carried out on ex vivo bovine femur and tibia, subjected to MWA. An overall of 40 measurement points covering a large sensing area was obtained for each configuration. Temperature monitoring was performed by using 40 fiber Bragg grating (FBGs) sensors (four arrays each housing 10 FBGs), inserted into the bones at specific distances to the microwave antenna. As result, the ability of this experimental multi-point monitoring approach in tracking temperature variations within bone tissue during MWA treatments was shown. This study lays the foundations for the design of a novel approach to study the effects of MWA on bone tumors. As consequence, the MWA treatment settings could be optimized in order to maximize the treatment effects of such a promising clinical application, but also customized for the specific tumor and patient.

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15

Ni, Jing, Yang Wang, Zhen Meng, Jun Cai, Kai Feng, and Hongwei Zhang. "Model of Ploughing Cortical Bone with Single-Point Diamond Tool." Materials 14, no. 21 (October 29, 2021): 6530. http://dx.doi.org/10.3390/ma14216530.

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Generating topological microstructures on the surface of cortical bone to establish a suitable microenvironment can guide bone cells to achieve bone repair. Single-point diamond tools (SPDTs) have advantages in efficiency and flexibility to fabricate surface microstructures. However, the cutting force during ploughing cannot be predicted and controlled due to the special properties of cortical bone. In this paper, a novel cutting model for ploughing cortical bone using an SPDT was established, and we comprehensively considered the shear stress anisotropy of the bone material and the proportional relationship between the normal force and the tangential force. Then, the orthogonal cutting experiment was used to verify the model. The results show that the error of calculated value and the experimental data is less than 5%. The proposed model can be used to assist the fabrication of microstructures on cortical bone surface using an SPDT.

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Xi, Li-Cheng, Hong-Yu Li, Ming Zhang, and Si-Cheng Huang. "Effects of bone cement filling in rabbit proximal femoral medullary cavity on distal femoral blood flow and metabolism." Journal of International Medical Research 46, no. 12 (October 14, 2018): 5237–44. http://dx.doi.org/10.1177/0300060518802717.

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Objective A rabbit model was used to evaluate the effects of bone-cemented hip arthroplasty on distal femoral blood flow and metabolism relative to that of the non-cemented contralateral leg. Methods The marrow cavity of the right hind femur was filled with bone cement. At each of the following time points, rabbits were randomly selected to receive an injection of one dose of 99mTc-methylene diphosphonate and then immediately scanned using a gamma camera: immediately postoperatively and at 4 and 8 weeks postoperatively. A BL-410 model biofunction experimental system was used to analyze the acquired images and determine the radioactive counts of each hind leg. Results The X-ray and photographic images of the right femoral bones confirmed successful filling of the marrow cavity with bone cement. The radioactive counts were significantly lower in the experimental than control legs at each time point. The ratio of the radioactive count of the experimental to control leg increased considerably at each time point, but each ratio was <1. Conclusion Blocking the proximal femoral medullary cavity with bone cement was associated with significant lowering of the blood circulation of the femur and marrow, decreasing the distal femoral blood flow and bone metabolic rate.

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Johari, Masume, Farzaneh Kaviani, and Arman Saeedi. "Relationship Between the Thickness of Cortical Bone at Maxillary Mid-palatal Area and Facial Height Using CBCT." Open Dentistry Journal 9, no. 1 (July 31, 2015): 287–91. http://dx.doi.org/10.2174/1874210601509010287.

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Introduction : Orthodontic mini-implants have been incorporated into orthodontic treatment modalities. Adequate bone at mini-implant placement site can influence the success or failure of anchorage. The present study was to determine the thickness of cortical bone in the maxillary mid-palatal area at predetermined points for the placement of orthodontic mini-implants using Cone Beam CT technique in order to evaluate the relationship of these values with the facial height. Materials and Methods : A total of 161 patients, consisting of 63 males (39.13%) and 98 females (60.87%), were evaluated in the present study; 38% of the subjects had normal facial height, 29% had short face and 33% had long face. In order to determine which patient belongs to which facial height category, i.e. normal, long or short, two angular and linear evaluations were used: the angle between S-N and Go-Me lines and the S-Go/N-Me ratio. Twenty points were evaluated in all the samples. First the incisive foramen was located. The paracoronal cross-sections were prepared at distances of 4, 8, 16 and 24 mm from the distal wall of the incisive foramen and on each cross-section the mid-sagittal and para-sagittal areas were determined bilaterally at 3- and 6-mm distances (a total of 5 points). The thicknesses of the cortical plate of bone were determined at the predetermined points. Results : There was a significant relationship between the mean cortical bone thickness and facial height (p<0.01), with significantly less thickness in long faces compared to short faces. However, the thickness of cortical bone in normal faces was similar to that in long and short faces. Separate evaluation of the points showed that at point a16 subjects with short faces had thicker cortical bone compared to subjects with long and normal faces. At point b8 in long faces, the thickness of the cortical bone was significantly less than that in short and normal faces. At point d8, the thickness of the cortical bone in subjects with short faces was significantly higher than that in subjects with long faces. Conclusion : At the point a16 the cortical bone thickness in short faces was significantly higher than normal and long faces. The lower thickness of the cortical bone in the palatal area at points b8 and d8 in subjects with long faces might indicate a lower anchorage value of these points in these subjects.

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Kwiecień, Małgorzata, Kornel Kasperek, Anna Winiarska-Mieczan, Anna Danek-Majewska, Katarzyna Kwiatkowska, Anna Arczewska-Włosek, Łukasz Jarosz, and Eva Zaricka. "Effect of Caponisation on Bone Development in Native Male Chickens." Annals of Animal Science 19, no. 4 (October 1, 2019): 991–1007. http://dx.doi.org/10.2478/aoas-2019-0057.

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AbstractThe aim of the study was to determine the effect of caponisation on the morphometric traits and mechanical parameters of tibial and femoral bones in Greenleg Partridge cocks. The experiment involved 200 cocks. At the age of 8 weeks, 100 birds were subjected to surgical castration. At week 24, the birds were slaughtered and tibial and femoral bones were collected from 10 non-caponised cocks and 10 capons. The caponisation surgery had no effect on the weight and length of any of the long bones but resulted in reduction (P≤0.05) of the ash content in both bones and Ca in the femur. It also influenced the geometric structure of the bones, i.e. there was an increase (P≤0.05) in the second moment of inertia in the tibial bone and the cross-sectional area and mean relative wall thickness in the femoral bone of the capons. The three-point bending test revealed a negative effect of caponisation on the mechanical strength of the bone. Values characterising the highest bone material strength, i.e. yielding load (femur), maximum force moment (tibia) and yielding deformation, bending point resistance, and load-to-deformation (both bones), declined in the capons. The investigations demonstrated a negative effect of caponisation on the quality of long bones. The tibial bone seems to be slightly more sensitive to the caponisation effects than the femoral bone. It can be assumed based on the analysis of biomechanical traits that the bones of capons are more susceptible to deformations or fractures due to their modified geometry and mechanical brittleness.

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Huang, Xiaowei, Andreas K. Nussler, Marie K. Reumann, Peter Augat, Maximilian M. Menger, Ahmed Ghallab, Jan G. Hengstler, Tina Histing, and Sabrina Ehnert. "Contribution to the 3R Principle: Description of a Specimen-Specific Finite Element Model Simulating 3-Point-Bending Tests in Mouse Tibiae." Bioengineering 9, no. 8 (July 25, 2022): 337. http://dx.doi.org/10.3390/bioengineering9080337.

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Bone mechanical properties are classically determined by biomechanical tests, which normally destroy the bones and disable further histological or molecular analyses. Thus, obtaining biomechanical data from bone usually requires an additional group of animals within the experimental setup. Finite element models (FEMs) may non-invasively and non-destructively simulate mechanical characteristics based on material properties. The present study aimed to establish and validate an FEM to predict the mechanical properties of mice tibiae. The FEM was established based on µCT (micro-Computed Tomography) data of 16 mouse tibiae. For validating the FEM, simulated parameters were compared to biomechanical data obtained from 3-point bending tests of the identical bones. The simulated and the measured parameters correlated well for bending stiffness (R2 = 0.9104, p < 0.0001) and yield displacement (R2 = 0.9003, p < 0.0001). The FEM has the advantage that it preserves the bones’ integrity, which can then be used for other analytical methods. By eliminating the need for an additional group of animals for biomechanical tests, the established FEM can contribute to reducing the number of research animals in studies focusing on bone biomechanics. This is especially true when in vivo µCT data can be utilized where multiple bone scans can be performed with the same animal at different time points. Thus, by partially replacing biomechanical experiments, FEM simulations may reduce the overall number of animals required for an experimental setup investigating bone biomechanics, which supports the 3R (replace, reduce, and refine) principle.

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Supawannawiwat, Thanawan, Chottiwat Tansirisithikul, and Bunpot Sitthinamsuwan. "Temporal Bone Landmarks of the Transversesigmoid Sinus Junction: An Anatomical Study in Dried Human Skulls." Siriraj Medical Journal 73, no. 11 (November 1, 2021): 738–43. http://dx.doi.org/10.33192/smj.2021.95.

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Objective: To investigate the accuracy in localization of the anterosuperior margin of TSSJ by using the intersection point between the squamosal and parietomastoid sutures (A point) and the intersection of the squamosal suture and supramastoid crest (B point) as bony landmarks.Materials and Methods: The A and B points were marked on the inner surface of a skull by using the transillumination technique. The anatomical relationship between the projected A point, B point, and groove of TSSJ was investigated in 60 dried Thai human skulls (120 sides).Results: Of the 120 sides, the projected A points were located exactly on the anterosuperior margin of the TSSJ in 38 (31.7%) instances and adjacent (above and below) the anterosuperior margin in 82 (68.3%) cases. Of the 118 sides with identifiable supramastoid crests, the projected B points were located precisely on the anterosuperior margin of TSSJ in 60 (50.8%) cases and above the anterosuperior margin of the TSSJ in 57 (48.3%) cases. Hence, the projected B point was a more reliable bony landmark for localizing the anterosuperior margin of the TSSJ when compared with the projected A point (p = 0.003, OR 2.2, and 95% CI =1.3-3.8).Conclusion: The B point is a more reliable temporal bone landmark for localization of the TSSJ than the A point. In temporal craniotomy, an initial burr hole at the B point is relatively safe and carries a very low risk of inadvertent venous sinus injury.

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Goto, Koji, Keiichi Kawanabe, Shunsuke Fujibayashi, R. Kowalski, and Takashi Nakamura. "Bone-Bonding Strength of a New Composite Bone Cement." Key Engineering Materials 330-332 (February 2007): 827–30. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.827.

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A composite bone cement designated G2B1 that contains β tricalcium phosphate particles was developed as a bone substitute for percutaneous transpedicular vertebroplasty. In this study, both G2B1 and commercial PMMA bone cement (CMW1) were implanted into proximal tibiae of rabbits with a metal frame fixed on it, and their bone-bonding strengths were evaluated at 4, 8, 12 and 16 weeks after implantation using a detaching test. Some of the specimens were evaluated histologically using Giemsa surface staining and scanning electron microscopy (SEM). It was found that the bone-bonding strength of G2B1 was significantly higher than that of CMW1 at each time point, and significantly increased from 4 weeks to 8 and 12 weeks, while it decreased significantly from 12 weeks to 16 weeks. Giemsa surface staining and SEM showed that G2B1 contacted bone directly without intervening soft tissue in the specimens at each time point, while there was always a soft tissue layer between CMW1 and bone. The results indicate that G2B1 has excellent bioactivity.

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22

Mohd Ghazali, Farah Amira, and Ardiyansyah Syahrom. "Mechanical Behaviour of Cancellous bone: Compression and Three-Point Bending Test." Malaysian Journal of Fundamental and Applied Sciences 18, no. 3 (August 4, 2022): 295–303. http://dx.doi.org/10.11113/mjfas.v18n3.2274.

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The mechanical properties of cancellous bone are fundamental in providing structural support and flexibility during physical activities. Characterization of cancellous bone properties and its mechanical behaviour were found crucial as information of the elastic and failure properties of the tissue may potentially be used to study the effects of drug treatments, aging and disease at the tissue level. This study aims to present the difference of mechanical properties of cancellous bone between compressive and three-point bending loads. Cancellous bone specimens from the femoral and tibial condyles of bovines were mechanically tested using three-point bending test and compression test and correlated with morphological parameters such as bone volume fraction and porosity. From the results, significant difference of mechanical properties was found between cancellous bone specimens tested with compressive and three-point bending load. From compressive load, the maximum stress reached 4.2 MPa, whereas in three-point bending, maximum flexural stress reached 17.0 MPa. Cancellous bone strength was found to be much higher when tested with three-point bending load, although correlations with morphological parameters such as bone volume fraction (BV/TV) and porosity were found lower compared to that in compressive load. In conclusion, there are no correlation between compression and three-point bending with morphology indices (BV/TV and porosity).

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23

Gallant, Maxime A., Drew M. Brown, Jason M. Organ, Matthew R. Allen, and David B. Burr. "Reference-point indentation correlates with bone toughness assessed using whole-bone traditional mechanical testing." Bone 53, no. 1 (March 2013): 301–5. http://dx.doi.org/10.1016/j.bone.2012.12.015.

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24

Kaur, Amandeep, and Kulwinder Singh Mann. "Segmenting Bone Parts for Bone Age Assessment using Point Distribution Model and Contour Modelling." Journal of Physics: Conference Series 933 (January 3, 2018): 012004. http://dx.doi.org/10.1088/1742-6596/933/1/012004.

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25

DANESI, VALENTINA, LUCA CRISTOFOLINI, MATEUSZ MARIA JUSZCZYK, PAOLO ERANI, and MARCO VICECONTI. "MECHANICAL PROPERTIES OF THE HUMAN METATARSAL BONES." Journal of Mechanics in Medicine and Biology 12, no. 04 (September 2012): 1250062. http://dx.doi.org/10.1142/s0219519412005034.

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Despite the incidence of metatarsal fractures and the associated risk of significant disability, little is known about the biomechanical properties (strength and stiffness) of metatarsal bones. In most cases a single metatarsal bone (first, second and fifth) has been investigated. An extensive investigation of the biomechanical properties of the metatarsal bones is essential in the understanding and prevention of metatarsal injuries. Entire sets of metatarsal bones from four feet were tested. The first foot was used to fine-tune the testing set-ups. To measure the stiffness, each metatarsal bone was subjected to non-destructive four-point-bending in the sagittal and transverse planes, axial compression and torsion. Strain was measured at two locations. To measure the strength, each metatarsal bone was tested to failure in torsion. Significant differences (p < 0.0001) existed among the stiffness of the five metatarsal bones: (i) in torsion the first metatarsal bone was 2–3 times stiffer than the others; (ii) in four-point-bending and axial compression this difference was less pronounced than in torsion; (iii) differences were smaller among the other metatarsal bones; (iv) the second metatarsal bone was less stiff than the third and fourth in bending. The second, third and fourth metatarsal bones were stiffer in the sagittal than in the transverse plane (p < 0.0001). Conversely, there was no significant difference between the two planes of bending for the first and fifth bones. During destructive testing, all metatarsal bones exhibited a linear elastic behavior and brittle failure. The torsional strength at failure ranged between 1.9 Nm and 6.9 Nm. The first metatarsal bone was stronger than all the others. Stiffness in different loading conditions and failure were measured and compared for all metatarsal bones. These data corroborate previous biomechanical studies concerning the role and load sharing of the different metatarsal bones.

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26

Kumar Punjabi, Dr Suneel, Dr Kashif Ali Channar, Dr Munir Ahmed Banglani, Dr Naresh Kumar, and Dr Ambreen Munir. "ISOLATED ZYGOMATIC BONE FRACTURE; MANAGEMENT BY THREE POINT FIXATION." PROFESSIONAL MEDICAL JOURNAL 23, no. 05 (May 1, 2016): 526–30. http://dx.doi.org/10.17957/tpmj/16.2934.

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27

Fukagawa, Masafumi, Yasuhiro Hamada, Shohei Nakanishi, and Motoko Tanaka. "The kidney and bone metabolism: Nephrologists' point of view." Journal of Bone and Mineral Metabolism 24, no. 6 (October 25, 2006): 434–38. http://dx.doi.org/10.1007/s00774-006-0719-7.

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28

Deschaseaux, Frédéric, Charalampos Pontikoglou, and Luc Sensébé. "Bone regeneration: the stem/progenitor cells point of view." Journal of Cellular and Molecular Medicine 14, no. 1-2 (August 10, 2009): 103–15. http://dx.doi.org/10.1111/j.1582-4934.2009.00878.x.

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29

Buhler, Joe P. "Acoustic analysis of bone using point-source-like transducers." Journal of the Acoustical Society of America 112, no. 5 (2002): 1742. http://dx.doi.org/10.1121/1.1526587.

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30

Idkaidek, Ashraf, Vineet Agarwal, and Iwona Jasiuk. "Finite element simulation of Reference Point Indentation on bone." Journal of the Mechanical Behavior of Biomedical Materials 65 (January 2017): 574–83. http://dx.doi.org/10.1016/j.jmbbm.2016.08.031.

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31

Gupta, Himadri S., Wolfgang Wagermaier, Gerald A. Zickler, Jürgen Hartmann, Sérgio S. Funari, Paul Roschger, H. Daniel Wagner, and Peter Fratzl. "Fibrillar level fracture in bone beyond the yield point." International Journal of Fracture 139, no. 3-4 (June 2006): 425–36. http://dx.doi.org/10.1007/s10704-006-6635-y.

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32

Ferrari, Stefano, Alba Balladelli, Emanuela Palmerini, and Daniel Vanel. "Imaging in bone sarcomas. The chemotherapist's point of view." European Journal of Radiology 82, no. 12 (December 2013): 2076–82. http://dx.doi.org/10.1016/j.ejrad.2011.11.028.

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33

Irwansyah, I., Jiing-Yih Lai, and Pei-Yuan Lee. "REPOSITIONING BONE FRAGMENTS USING REGISTRATION OF PAIRED-POINTS AND ASSISTED-CONSTRAINTS IN VIRTUAL BONE REDUCTION SURGERY." Biomedical Engineering: Applications, Basis and Communications 31, no. 03 (May 27, 2019): 1950021. http://dx.doi.org/10.4015/s1016237219500212.

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When repositioning fractured bones in orthopedic surgery, correctness and accuracy are vital to allow the bone to regain the function and facial aesthetics of native uninjured bone. Various improvements to repositioning techniques have been proposed using points, curves, and surfaces to find correspondence between the fracture fragments. The aim of this study was to investigate the appropriate registration constraints for fractured bone reduction. One paired-point and three assisted-constraints registration methods were tested based on contralateral, landmark, and fracture line markers. The fractured proximal femur of a patient was used to compare the performance of these registration methods. Semi-automatic repositioning based on a singular value decomposition algorithm was performed to solve the problem of matching the data from two fragments. The repositioning results show that the proposed registration methods have great promise in assisting the user in defining the paired points, which is often difficult due to visibility limitations on images of fractured bone. Each of the proposed approaches was shown to yield different benefits. In terms of repositioning correctness, the use of contralateral constraints produced the smallest RMS error (1.853[Formula: see text]mm). The contralateral template method yielded the lowest fragment deviation error, but was not significantly superior to the other approaches. Fracture line-based constraints may potentially enable the relocation of fragments closest to pre-injured conditions.

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34

Turner, C. H. "Yield Behavior of Bovine Cancellous Bone." Journal of Biomechanical Engineering 111, no. 3 (August 1, 1989): 256–60. http://dx.doi.org/10.1115/1.3168375.

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The compressive yield strain was measured for 61 specimens of bovine cancellous bone from three distal femora. There was no significant relationship (p = 0.08, R2 = 0.051) between yield strain and the degree of trabecular orientation. There was a significant positive correlation (p<0.00001, R2 = 0.319) between yield strain and structural (apparent) density and significant negative correlation (p<0.0025, R2 = 0.145) between yield strain and bone density. Yield strain correlated best with bone solid volume fraction Vv (εy = 0.592 + 1.446vv, R2 = 0.337). The quantity, yield strain, is highly dependent on specific definitions of the yield point and the point of zero strain. For this study the yield point was defined by a 0.0003 offset criterion, and the point of zero strain was defined as the point where the tangent at 15 percent of yield crosses zero. The results using these definitions were compared with results using yield strain values determined by other definitions of the yield point and zero strain. The correlations between yield strain and trabecular orientation, structural density and bone density changed very little for differing definitions of yield. The results suggest that yield strain in cancellous bone is isotropic or independent of textural anisotropy, so the yield behavior may be characterized by a maximum strain yield criterion. The results also suggest that the primary mode of yield in cancellous bone is buckling of the trabeculae.

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35

Flodr, Patrik, Pavla Latalova, Petra Pusciznova, Tomas Pika, Jaroslav Bacovsky, Vlastimil Scudla, and Jiri Minarik. "Multiple Myeloma and Bone Marrow Microenvironment Immunohistochemical Study of the Expression of 15 Proteins Related to Myeloma Bone Disease." Blood 126, no. 23 (December 3, 2015): 5318. http://dx.doi.org/10.1182/blood.v126.23.5318.5318.

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Abstract Objective: Neoplastic milieu is an integral part of all malignant diseases including multiple myeloma and plays variable role in their development, retention/adhesivity, resistency or sensitivity to therapeutic approach, homing and also paraneoplastic manifestations. Relatively genetically stable milieu may play an important role in new specific molecular therapeutic approaches and therefore should be contextually studied with neoplastic cells as complex neoplastic tissues. The expressions of 15 proteins with close relation to the development of myeloma bone disease (MBD) were analysed in consecutive multiple myeloma specimens. Methods: Bone marrow trephine biopsy specimens (n=57) with multiple myeloma were included in our prospective study. FFPE tissues were processed in app. 5microm sections and placed on charged slides. The indirect immunohistochemical staining was applicated after antigen retrieval and commercial primary antibodies were used for the detection of observed proteins. Standard secondary antibody and ABC method were included in visualisation. We analysed the expressions of MIP1alfa, Annexin A2, TRAP, DKK-1, RANK, RANKL, OPG, Sclerostin, Activin A, NFkappaB proteins (p50, p52, p65), p62 (sequestosome 1), MMP9 and RUNX2. Results: Bone marrow multiple myeloma specimens showed variable positivity of MIP1alfa in 60% (cut-off point 20%), Annexin A2 in 42% (myeloma cells, cut-off point 30%) and in 74% (stromal cells, cut-off point 5%), TRAP in 28% (cut-off point 5%), DKK-1 in 23% (cut-off point 30%), RANK in 53% (cut-off point 30%), RANKL in 70%, OPG in 39% (cut-off point 5%), Sclerostin in 95% (cut-off point 90%), Activin A in 35% (cut-off point 30%), cytoplasmic positivity of p50 in 5% (cut-off point 10%), p52 in 86% (cut-off point 10%), p62 in 91% (cut-off point 10%), p65 in 89% (cut-off point 10%), positivity of MMP9 in 22% (cut-off point 30%) and positivity of RUNX2 in 56% (cut-off point 30%). Conclusion: Our study showed variable expression of proteins related to MBD in multiple myeloma and its bone marrow microenvironment that imply biological heterogeneity, different development and stromal plasticity in this complex hemato-oncological disease. The exact and contextual knowledge of the engaged signaling pathways may suggest more specific or tailored therapeutic approaches (e.g. anti-RANKL, anti-DKK-1, anti-Sclerostin, anti-Activin A). Supported by the grant NT 14393. Disclosures No relevant conflicts of interest to declare.

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36

Waters, Michael R., Thomas W. Stafford, Brian G. Redmond, and Kenneth B. Tankersley. "The Age of the Paleoindian Assemblage at Sheriden Cave, Ohio." American Antiquity 74, no. 1 (January 2009): 107–11. http://dx.doi.org/10.1017/s0002731600047521.

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Direct dating of a Paleoindian bone point from Sheriden Cave, Ohio, yielded a radiocarbon age of 10,915 ± 30 ¹⁴C yr B.P. (UCIAMS-38249). This date was derived on highly purified bone collagen. This bone point was found in association with another bone projectile point and a reworked, fluted Clovis projectile point. The artifacts from Sheriden Cave fall within the age range of other Clovis sites in North America, dating to the late Allerød, before the start of the Younger Dryas.

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37

Li, Zekun, Baolong Guo, and Fanjie Meng. "Fast Shape Recognition via the Restraint Reduction of Bone Point Segment." Symmetry 14, no. 8 (August 11, 2022): 1670. http://dx.doi.org/10.3390/sym14081670.

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In computer science, and especially in computer vision, the contour of an object is used to describe its features; thus, the shape descriptor plays an indispensable role in target detection and recognition. Further, Fourier is an important mathematical description method, and the Fourier transform of a shape contour has symmetry. This paper will demonstrate the symmetry of shape contour in the frequency domain. In recent years, increasing numbers of shape descriptors have come to the fore, but many descriptors ignore the details of shape. It is found that the most fundamental reason affecting the performance of shape descriptors is structural restraints, especially feature structure restraint. Therefore, in this paper, the restraint of feature structure that intrinsically deteriorates recognition performance is shown, and a fast shape recognition method via the Bone Point Segment (BPS) restraint reduction is proposed. An approach using the inner distance to find bone shapes and segment the shape contour by these bones is proposed. Then, Fourier transform is performed on each segment to form the shape feature. Finally, the restraints of the shape feature are reduced in order to build a more effective shape feature. What is commendable is that its discriminability and robustness is strong, the process is simple, and matching speed is fast. More importantly, the experiment results show that the shape descriptor has higher recognition accuracy and the matching speed runs up to more than 1000 times faster than the existing description methods like CBW and TCD. More importantly, it is worth noting that the recognition accuracy approaches 100% in the self-build dataset.

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38

Prakoonwit, Simant. "Towards Multiple 3D Bone Surface Identification and Reconstruction Using Few 2D X-Ray Images for Intraoperative Applications." International Journal of Art, Culture and Design Technologies 4, no. 1 (January 2014): 13–31. http://dx.doi.org/10.4018/ijacdt.2014010102.

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This article discusses a possible method to use a small number, e.g. 5, of conventional 2D X-ray images to reconstruct multiple 3D bone surfaces intraoperatively. Each bone's edge contours in X-ray images are automatically identified. Sparse 3D landmark points of each bone are automatically reconstructed by pairing the 2D X-ray images. The reconstructed landmark point distribution on a surface is approximately optimal covering main characteristics of the surface. A statistical shape model, dense point distribution model (DPDM), is then used to fit the reconstructed optimal landmarks vertices to reconstruct a full surface of each bone separately. The reconstructed surfaces can then be visualised and manipulated by surgeons or used by surgical robotic systems.

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39

Mullender, M., B. van Rietbergen, P. Rüegsegger, and R. Huiskes. "Effect of Mechanical Set Point of Bone Cells on Mechanical Control of Trabecular Bone Architecture." Bone 22, no. 2 (February 1998): 125–31. http://dx.doi.org/10.1016/s8756-3282(97)00251-2.

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40

Liu, Zhong-Yu, Jin-Li Zhang, Yang Zhang, Shi-Lian Kan, Jun Liang, and Pei-Jia Liu. "Repairing Rabbit Radius Bone Defects with Simvastatin Compound Biological Bone." Journal of Biomaterials and Tissue Engineering 11, no. 7 (July 1, 2021): 1263–70. http://dx.doi.org/10.1166/jbt.2021.2710.

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Objective: This study aimed to investigate the feasibility of repairing rabbit radius bone defects with simvastatin compound biological bone. Methods: Simvastatin biological bone material was prepared, and osteoblasts were cultured. A total of 42 New Zealand white rabbits were randomly divided into four groups, and a bone defect with a length of 15 mm was created at the middle part of the radial shaft of both limbs in each rabbit, thereby establishing a bone defect model. The grafts in group A were biological bones of osteoblasts combined with simvastatin; the grafts in group B were biological bones of simvastatin; the grafts in group C were biological compound bones of osteoblasts; and the grafts in group D were simple biological bones. In each group, four animals were randomly sacrificed at the sixth and twelfth week after surgery, and specimens were collected for gross observation, X-ray examination, histological observation, and biomechanical testing. In each group, two animals were randomly sacrificed at the twelfth week after surgery; a three-point bending test was performed using a biomechanical testing machine, and the results were compared with those of a normal radius. Results: The X-ray and histological examinations at 6 and 12 weeks after surgery revealed that the osteogenesis ability of the simvastatin biological bone and osteoblast-simvastatin biological bone was better than that of the osteoblast biological bone and simple biological bone, which was superior in group A and group B to group C and group D. The results of the biomechanical examination revealed that the maximum stress of the normal radius was significantly higher than that of the experimental groups. Among the experimental groups, the difference between group A and group B was not statistically significant, and the maximum stress was higher in groups A and B than in groups C and D. Conclusion: Simvastatin biological bone material can promote the repair of rabbit radius defects and increase the quality of bone healing.

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Fu, Donghui, Zhende Hou, Qing-Hua Qin, Lianyun Xu, and Yanjun Zeng. "Influence of Shear Stress on Behaviors of Piezoelectric Voltages in Bone." Journal of Applied Biomechanics 28, no. 4 (August 2012): 387–93. http://dx.doi.org/10.1123/jab.28.4.387.

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The piezoelectric properties of bone play an important role in the bone remodeling process and can be employed in clinical bone repair. In this study, the piezo-voltage of bone between two surfaces of a bone beam under bending deformation was measured using an ultra-high-input impedance bioamplifier. The influence of shear stress on the signs of piezo-voltages in bone was determined by comparing and contrasting the results from three-point and four-point bending experiments. From the three-point bending experiment, the study found that the signs of piezo-voltages depend only on shear stress and are not sensitive to the normal stress.

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Guimarães, Márica B. "Fishing strategies among prehistoric populations at Saquarema Lagoonal Complex, Rio de Janeiro, Brazil." Anais da Academia Brasileira de Ciências 85, no. 1 (March 2013): 415–29. http://dx.doi.org/10.1590/s0001-37652013005000005.

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Two distinct fishing technologies were identified among the shellmound builders of the Saquarema Lagoonal Complex, in the Brazilian state of Rio de Janeiro: bone point technology and worked fish spines. These technologies were related to the acquisition of specific fish resources; Worked fish spines were used in the capture of Micropogonias furnieri (Desmarest), and bone points used for fishing specimens of the Ariidae family. Worked spines technology was predominant between 6,726 cal. years BP and 3,699 cal. years BP, while the bone point technology was dominant after 3,699 cal. years BP. It is believed these different strategies for obtaining fishing resources before 3,699 years cal. BP was related to environmental. Notably the gradual regression of relative sea level occurred during the mid- and late Holocene.

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აწყვერელი ლ., Atskvereli L., Bregadze O. ბრეგაძე ო., and Chuchulashvili N. ჭუჭულაშვილი ნ. "NASAL BONE RECONSTRUCTION USING BONE CEMENT - “SURGICAL SIMPLEX P”." TSMU COLLECTION OF SCIENTIFIC WORKS 49 (April 11, 2019): 8–10. http://dx.doi.org/10.52340/csw.v49i0.138.

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Surgical treatment of the defects and deformations in the facial area are still actual problems of reconstructive surgery. Medical and social aspects of the problem, pushes for intense search of the new materials for the reconstruction and improvement of surgical methods. The work presents an interesting clinical case description. The authors successfully used radiopaque medical cement “Surgical Simplex P” to fill in the deficit of the nasal bone and cartilage. It should be noted that the satisfactory effect was achieved in both functional and aesthetic point of view.

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Gomes, Nathália R., Juliano D. S. Albergaria, Jonathas A. de S. Henriques, Tânia M. P. Amaral, Evandro N. Abdo, Gerluza A. B. Silva, and Cláudia Borges Brasileiro. "Comparison between fractal analysis and radiopacity evaluation as a tool for studying repair of an osseous defect in an animal model using biomaterials." Dentomaxillofacial Radiology 48, no. 7 (October 2019): 20180466. http://dx.doi.org/10.1259/dmfr.20180466.

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Objectives: To evaluate bone repair of an osseous defect in a rat animal model through fractal analysis and radiopacity analysis in radiographic images. Methods: 120 rats were subjected to extraction of their first molar and divided into four groups (n = 6/group) according to the material used for bone grafting: mineralized bovine bone, demineralized bovine bone (DBB), blood clot (BC - control) or Bio-Oss® (BO). The animals were sacrificed after 1, 7, 14, 21 and 49 days and subjected to radiographic evaluation. For fractal analysis (FA), a square regionof interest of 30 × 30 pixels was used, and radiopacity was measured as the mean gray scale (MGS) value for three points of 5 × 5 pixels in the apical, medial and coronal regions of the defect. Histomorphometric evaluation was realized as the gold standard for bone neo-formation and maturation of the new osseous matrix. Results: Histomorphometric evaluation suggested that DBB showed faster mineralized deposition and resulted in more mature bone at the final time point of evaluation. Mineralized bovine bone and Bio-Oss presented similar results. The mineralized groups did not show significant differences in bone maturation. The radiopacity analysis revealed a significant difference (p < 0.05) between the DBB and blood clot groups at the final time point. FA did not show any significant differences at the final time point. Conclusions: Mean gray scale seemed to be more effective for the quantification of bone repair than FA in the demineralized group in this animal model. Results for the mineralized groups did not reveal a significant difference, leading to the conclusion that both methods are effective.

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45

Azuma, Kotaro, Stephanie C. Casey, Masako Ito, Tomohiko Urano, Kuniko Horie, Yasuyoshi Ouchi, Séverine Kirchner, Bruce Blumberg, and Satoshi Inoue. "Pregnane X receptor knockout mice display osteopenia with reduced bone formation and enhanced bone resorption." Journal of Endocrinology 207, no. 3 (September 27, 2010): 257–63. http://dx.doi.org/10.1677/joe-10-0208.

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The steroid and xenobiotic receptor (SXR) and its murine ortholog pregnane X receptor (PXR) are nuclear receptors that are expressed mainly in the liver and intestine where they function as xenobiotic sensors. In addition to its role as a xenobiotic sensor, previous studies in our laboratories and elsewhere have identified a role for SXR/PXR as a mediator of bone homeostasis. Here, we report that systemic deletion of PXR results in marked osteopenia with mechanical fragility in female mice as young as 4 months old. Bone mineral density (BMD) of PXR knockout (PXRKO) mice was significantly decreased compared with the BMD of wild-type (WT) mice. Micro-computed tomography analysis of femoral trabecular bones revealed that the three-dimensional bone volume fraction of PXRKO mice was markedly reduced compared with that of WT mice. Histomorphometrical analysis of the trabecular bones in the proximal tibia showed a remarkable reduction in bone mass in PXRKO mice. As for bone turnover of the trabecular bones, bone formation is reduced, whereas bone resorption is enhanced in PXRKO mice. Histomorphometrical analysis of femoral cortical bones revealed a larger cortical area in WT mice than that in PXRKO mice. WT mice had a thicker cortical width than PXRKO mice. Three-point bending test revealed that these morphological phenotypes actually caused mechanical fragility. Lastly, serum levels of phosphate, calcium, and alkaline phosphatase were unchanged in PXRKO mice compared with WT. Consistent with our previous results, we conclude that SXR/PXR promotes bone formation and suppresses bone resorption thus cementing a role for SXR/PXR as a key regulator of bone homeostasis.

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Kempa, Stepan, Michael Martin, and Ernst Dalhoff. "Automated human temporal-bone experiments." Current Directions in Biomedical Engineering 8, no. 2 (August 1, 2022): 400–403. http://dx.doi.org/10.1515/cdbme-2022-1102.

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Abstract Temporal-bone (TB) experiments are useful for the investigation of middle-ear and inner-ear transfer properties, and the analysis and development of active or passive middleear prostheses or related devices. To acquire the mechanical middle-ear (ME) response, the Laser-Doppler vibrometry (LDV) is utilized as a preferred method. In most setups, the exact measurement point chosen on the biological structure of interest as well as the direction of the corresponding vibration measurement is not precisely defined and of unknown reproducibility. Hence, an automated setup controlling coordinates of TB and measurement direction is developed and tested. To test the reproducibility, TBs were measured with ER7C and ER10C probe microphones employing a small industrial robot to position the TB to the ME points of interest and align it to the laser beam. The position and vibration data acquired at the same locations at different points of time were processed and compared. Measured transfer functions indicate noticeable differences at some frequency ranges. Nonetheless, the reproducibility of positioning to repeatedly measured points proved itself relatively accurate, if no manipulations in the setup are made. In conclusion, the current study shows that automated LDV TB measurement system is in principle capable to adapt to the changes in setup during intermediate preparation steps. With more acquired data, the setup stability and reproducibility can be more precisely verified, and additional improvements can be made.

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Heo, S. Y., H. B. Lee, K. C. Lee, M. S. Kim, C. S. Na, and N. S. Kim. "Biomechanical assessment of freeze-dried allograft cortical bone plate graft in canine bone defect model." Veterinární Medicína 54, No. 4 (May 12, 2009): 183–90. http://dx.doi.org/10.17221/3029-vetmed.

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Freeze-dried cortical bone can be used as a biological plate, either alone or in combination with other internal fixation devices, to stabilize fractures. In addition to it conferring mechanical stability, freeze-dried cortical bone may enhance fracture-healing and increase the bone stock. This study examined the effect of a freeze-dried allograft cortical bone plate (FACBP) on the biomechanical properties of an implant site in a canine bone defect model. Twelve adult mongrel dogs (around 4.8 kg) were used. A segmental critical-size defect (5 mm in length) at ulna diaphysis was created using an oscillating saw. The experimental animals were divided into two groups: eight dogs treated with an absorbable bone plate (FACBP) fixed by metal bone screws (Group A) and four dogs treated with a commercial stainless steel bone plate and metal bone screws (Group B). Bone healing was assessed by radiography, Dual-energy x-ray absorptiometry and a three-point bending test. The FACBP incorporated in the host bone produced complete remodeling of the cortical bone. There was no significant difference in the bone mineral density and biomechanical tests between the FACBP application site and normal ulna or a stainless steel bone plate of the ulna. These results suggest that FACBP facilitates recovery from a bone fracture by assisting in the induction of new bone formation in a defected fracture.

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Kneser, U., D. J. Schaefer, E. Polykandriotis, and R. E. Horch. "Tissue engineering of bone: the reconstructive surgeon's point of view." Journal of Cellular and Molecular Medicine 10, no. 1 (January 2006): 7–19. http://dx.doi.org/10.1111/j.1582-4934.2006.tb00287.x.

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49

IKOMA, Toshiyuki, and Junzo TANAKA. "Artificial Bone Analyzed from the View Point of Interfacial Structure." Hyomen Kagaku 32, no. 9 (2011): 545–50. http://dx.doi.org/10.1380/jsssj.32.545.

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50

Wise, Sarah K., Gamwell A. Rogers, Mark D. Ghegan, Richard J. Harvey, John M. DelGaudio, and Rodney J. Schlosser. "Radiologic staging system for allergic fungal rhinosinusitis (AFRS)." Otolaryngology–Head and Neck Surgery 140, no. 5 (May 2009): 735–40. http://dx.doi.org/10.1016/j.otohns.2008.12.053.

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Objectives: 1) Develop an objective method for quantifying radiologic bone erosion in allergic fungal rhinosinusitis (AFRS); and 2) assess the utility of the new CT scan staging system in differentiating AFRS patient groups. Methods: Patients from two tertiary care rhinology practices with AFRS and available CT scans (1999–2007) were included for review by trained graders. The following novel assessment scale was used: Each paranasal sinus wall with expansion/erosion was scored 1 point, with maximum 3 points possible for each frontal sinus, 2 points for each ethmoid complex, 3 points for each sphenoid sinus, 3 points for each maxillary sinus, and 1 point each for the frontal and sphenoid intersinus septae, yielding maximum of 24 possible points. Results: A total of 111 CT scans were reviewed. Mean score was 7.8 (range, 0–24). Males scored significantly higher than females (mean, 9.3 vs 5.6, P = 0.001). African Americans scored significantly higher than Caucasians (mean, 9.6 vs 5.0, P < 0.001). Conclusions: A scoring system for bone remodeling in AFRS is presented. Males and African-Americans with AFRS demonstrate significantly more bone erosion. Additional analysis of disease course will assess the utility of this staging system in predicting outcomes.

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