Computer Simulation of Human Mandibular Bone Structure by iBone, a Novel Reaction-Diffusion Bone Remodeling Model

Bone is a complex system with adaptation and repair functions. To understand how bone cells can create a structure adapted to the mechanical environment, we proposed a simple bone remodeling model, iBone, based on a reaction-diffusion system [1]. A 3-dimensional mandibular bone model consisting of approximately 1.4 million elements was constructed from sequential computer tomography (CT) images of a 14-year old female. Both teeth and bone were modeled with isoparametric voxel elements with Young's Modulus = 20 GPa and Poisson's ratio = 0.3. Both heads of the mandible were fixed allowing rotation and horizontal movement. Teeth were fixed vertically allowing horizontal movements. Incisor, right/left group, and right/left molar biting conditions were simulated. The locations and directions of muscles, and their forces were predicted from the CT images. Remodeling simulation was performed by 10 sets of finite element method analysis and reaction-diffusion remodeling simulation to obtain internal structure adapted to each loading condition. As a result, the major part of the corpus of the simulated mandibular bone showed similar internal structures under different biting conditions. Moreover, these simulated structures were satisfactorily similar to that of the real mandible. Computer simulation of three-dimensional bone structures based on CT images will be very useful for understanding the patho-physiological state of bone under various mechanical conditions, and may assist orthopedic doctors to predict the risk and efficacy of surgical therapies.

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Structural Topology Optimization Method Based on Bone Remodeling

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.423-426.1813 ◽

2013 ◽

Vol 423-426 ◽

pp. 1813-1818

Author(s):

Kaysar Rahman ◽

Nurmamat Helil ◽

Rahmatjan Imin ◽

Mamtimin Geni

Keyword(s):

Topology Optimization ◽

Bone Remodeling ◽

Bone Structure ◽

Reaction Diffusion ◽

Optimization Method ◽

Mechanical Stimulus ◽

Bone Adaptation ◽

Reaction Diffusion Equations ◽

Structural Topology Optimization ◽

Structural Topology

Bone is a dynamic living tissue that undergoes continuous adaptation of its mass and structure in response to mechanical and biological environment demands. In this paper, we firstly propose a mathematical model based on cross-type reaction diffusion equations of bone adaptation during a remodeling cycle due to mechanical stimulus. The model captures qualitatively very well the bone adaptation and cell interactions during the bone remodeling. Secondly assuming the bone structure to be a self-optimizing biological material which maximizes its own structural stiffness, bone remodeling model coupled with finite element method by using the add and remove element a new topology optimization of continuum structure is presented. Two Numerical examples demonstrate that the proposed approach greatly improves numerical efficiency, compared with the others well known methods for structural topology optimization in open literatures.

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Faculty Opinions recommendation of Effects of intravenous zoledronic acid once yearly on bone remodeling and bone structure.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1097700.553810 ◽

2008 ◽

Author(s):

Peter Ebeling ◽

Claudia Gagnon

Keyword(s):

Zoledronic Acid ◽

Bone Remodeling ◽

Bone Structure

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Local administration of calcitriol positively influences bone remodeling and maturation during restoration of mandibular bone defects in rats

Materials Science and Engineering C ◽

10.1016/j.msec.2014.12.064 ◽

2015 ◽

Vol 49 ◽

pp. 14-24 ◽

Cited By ~ 16

Author(s):

Hongrui Liu ◽

Jian Cui ◽

Wei Feng ◽

Shengyu Lv ◽

Juan Du ◽

...

Keyword(s):

Bone Remodeling ◽

Bone Defects ◽

Local Administration ◽

Mandibular Bone

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Energy Metabolism of Bone

Toxicologic Pathology ◽

10.1177/0192623317737065 ◽

2017 ◽

Vol 45 (7) ◽

pp. 887-893 ◽

Cited By ~ 10

Author(s):

Katherine J. Motyl ◽

Anyonya R. Guntur ◽

Adriana Lelis Carvalho ◽

Clifford J. Rosen

Keyword(s):

Bone Remodeling ◽

Energy Homeostasis ◽

Bone Structure ◽

Bone Cells ◽

Bone Cell ◽

Whole Body ◽

Blood Calcium ◽

Micro Cracks ◽

Intimate Link ◽

Body Energy

Biological processes utilize energy and therefore must be prioritized based on fuel availability. Bone is no exception to this, and the benefit of remodeling when necessary outweighs the energy costs. Bone remodeling is important for maintaining blood calcium homeostasis, repairing micro cracks and fractures, and modifying bone structure so that it is better suited to withstand loading demands. Osteoclasts, osteoblasts, and osteocytes are the primary cells responsible for bone remodeling, although bone marrow adipocytes and other cells may also play an indirect role. There is a renewed interest in bone cell energetics because of the potential for these processes to be targeted for osteoporosis therapies. In contrast, due to the intimate link between bone and energy homeostasis, pharmaceuticals that treat metabolic disease or have metabolic side effects often have deleterious bone consequences. In this brief review, we will introduce osteoporosis, discuss how bone cells utilize energy to function, evidence for bone regulating whole body energy homeostasis, and some of the unanswered questions and opportunities for further research in the field.

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Osteoblast and Osteoclast Activity Affect Bone Remodeling Upon Regulation by Mechanical Loading-Induced Leukemia Inhibitory Factor Expression in Osteocytes

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2020.585056 ◽

2020 ◽

Vol 7 ◽

Author(s):

Jingke Du ◽

Jiancheng Yang ◽

Zihao He ◽

Junqi Cui ◽

Yiqi Yang ◽

...

Keyword(s):

Bone Remodeling ◽

Mechanical Loading ◽

Leukemia Inhibitory Factor ◽

Fluid Shear Stress ◽

Bone Structure ◽

Inhibitory Factor ◽

Tartrate Resistant Acid Phosphatase ◽

Osteoclast Activity ◽

Microgravity Simulation

PurposeBone remodeling is affected by mechanical stimulation. Osteocytes are the primary mechanical load-sensing cells in the bone, and can regulate osteoblast and osteoclast activity, thus playing a key role in bone remodeling. Further, bone mass during exercise is also regulated by Leukemia inhibitory factor (LIF). This study aimed to investigate the role of LIF in the mechanical response of the bone, in vivo and in vitro, and to elucidate the mechanism by which osteocytes secrete LIF to regulate osteoblasts and osteoclasts.MethodsA tail-suspension (TS) mouse model was used in this study to mimic muscular disuse. ELISA and immunohistochemistry were performed to detect bone and serum LIF levels. Micro-computed tomography (CT) of the mouse femurs was performed to measure three-dimensional bone structure parameters. Fluid shear stress (FSS) and microgravity simulation experiments were performed to study mechanical stress-induced LIF secretion and its resultant effects. Bone marrow macrophages (BMMs) and bone mesenchymal stem cells (BMSCs) were cultured to induce in vitro osteoclastogenesis and osteogenesis, respectively.ResultsMicro-CT results showed that TS mice exhibited deteriorated bone microstructure and lower serum LIF expression. LIF secretion by osteocytes was promoted by FSS and was repressed in a microgravity environment. Further experiments showed that LIF could elevate the tartrate-resistant acid phosphatase activity in BMM-derived osteoclasts through the STAT3 signaling pathway. LIF also enhanced alkaline phosphatase staining and osteogenesis-related gene expression during the osteogenic differentiation of BMSCs.ConclusionMechanical loading affected LIF expression levels in osteocytes, thereby altering the balance between osteoclastogenesis and osteogenesis.

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