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1

Safe rebuilding of the periodontal loss an experimental study

Minch L. E., Słowiński J. J., Scigala K., Będziński R., Kawala B.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 2

527--532

EN

This study aimed at the simulation of bone tissue remodeling within a bone defect with the utilization of the finite element method (FEM), enabling - via elaborated application - objective evaluation of orthodontic forces which positively influence periodontium in vivo. The initial position of each bracket on the passive archwire was registered, and then a geometrical and discretemodel of the appliance was created automatically. Assessment of the dental scans obtained using cone beam computed tomography (CBCT) allowed evaluation of the range of bracket displacement: from the initial position to the final one achieved on the active archwire. Those displacements established terminal conditions in the finite element analysis, enabling calculation of orthodontic force levels. An individual design of a tooth with periodontal ligaments and the periodontal defect subsequently loaded with the determined forces allowed simulation of bone remodeling according to Carters adaptation process. Mainly, the bone apposition processes took place in the central part of the periodontal defect, in proximity of the alveolar ridge. However, FEM application in the analysis of bone tissue regeneration within bone defects enables precise evaluation of the achieved changes, therefore allows determination of orthodontic forces positively influencing periodontium in vivo.

2

Komputerowy algorytm badania procesu przebudowy tkanki kostnej gąbczastej

Wrona A.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2014

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Vol. 20, nr 1

1--10

PL

Proces remodelingu kości polega na ciągłych zmianach adaptacyjnych w strukturze kostnej. Zmiany te widoczne są zarówno w tkance zbitej, jak i gąbczastej. W tkance gąbczastej uwidaczniają się poprzez zmiany architektury lub właściwości mechanicznych. Do momentu, dopóki równowaga pomiędzy resorpcją a nowotworzeniem kości nie jest zaburzona, przebudowa umożliwia dopasowanie się kości do zmiennych warunków. W momencie zachwiania wspomnianej równowagi resorpcja kości zaczyna przeważać nad procesami odbudowy. Takie zaburzenia pojawiają się również lokalnie w wyniku działania czynników zewnętrznych, np. takich jak endoproteza. W pracy zaprezentowano algorytm procesu adaptacji tkanki kostnej, który uwzględnia współdziałanie kilku czynników wpływających na strukturę kostną. Daje on możliwość przewidywania zmian w architekturze oraz właściwościach mechanicznych kości. Dzięki temu można dobrać optymalny sposób leczenia, np. w przypadku osteoporozy czy po alloplastyce stawu biodrowego.

EN

The bone remodeling is the process which is responsible for the continuous alteration of bone structure. These alterations are visible in cortical, and specially in the cancellous bone. This process is completely natural and rely on the balance between resorption and formation of a new bone. When the natural balance is impaired, the bone resorption dominates over the formation process. Locally, such disorders may be caused by external factors e.g. hip replacement. In this paper, an algorithm of functional adaptation of bone tissue, is proposed, enabling prediction of structural and mechanical changes. It can be helpful in planning of optimal treatment, e.g. in the case of osteoporosis or hip alloplasty.

3

Probabilistic study of bone remodeling using finite element analysis

Werner C., Gorla R. S. R.

International Journal of Applied Mechanics and Engineering

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2013

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Vol. 18, no. 3

911--921

EN

The dynamic bone remodeling process is a computationally challenging research area that struggles to understand the actual mechanisms. It has been observed that a mechanical stimulus in the bone greatly affects the remodeling process. A 3D finite element model of a femur is created and a probabilistic analysis is performed on the model. The probabilistic analysis measures the sensitivities of various parameters related to the material properties, geometric properties, and the three load cases defined as Single Leg Stance, Abduction, and Adduction. The sensitivity of each parameter is based on the calculated maximum mechanical stimulus and analyzed at various values of probabilities ranging from 0.001 to 0.999. The analysis showed that the parameters associated with the Single Leg Stance load case had the highest sensitivity with a probability of 0.99 and the angle of the force applied to the joint of the proximal femur had the overall highest sensitivity.

4

Mathematical Models and Numerical Simulation in Bone Remodeling

Viano J. M., Martínez R., Fernandez J. R., García-Aznar J. M.

Machine Dynamics Research

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2011

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Vol. 35, No. 1

123-134

EN

In this paper we summarize the work of the authors during the last years about the analysis and numerical simulation of bone remodeling process using well-known mathematical models.

5

Nanostructured bone-like scaffolds for restoration of trabecular bone remodeling capability

Nowak M., Firkowska I., Giersig M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2011

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Vol. 59, nr 1

57-61

EN

This paper presents the theoretical study about carbon nanotube substrates for tissue engineering and its applications. Because the replacement of bone tissue with artificial tissue can violate the remodeling process completely, the artificial material should not only consist of the same material properties, but also exhibit other characteristics which are equally important and need to be taken into consideration. These are above all the mechanosensation. Besides replacing natural tissue, the nanostructured scaffolds presented in the paper can help the tissue growth by stimulating this process. The developed trabecular bone remodeling simulation method responsible for the nanostructured scaffold behavior is implemented here. Thus, the nanostructured bone-like scaffolds reflect the remodeling capability of the biological system, not only due to their application as replacement of natural tissue, but also due to their effects in the field of mechanosensation.

6

Bone remodeling and bone adaptation

Petrtyl M., Danesova J.

Acta of Bioengineering and Biomechanics

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1999

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Vol. 1, nr 1

107-116

EN

Bone remodelling is a very complicated process that can be characterised as close relationship of biomechnical effects and biomechanical reactions. It is not possible to give an exact definition of the bone remodeling if we take into consideration the aspects related merely to biomechanics or to biochemistry. Biomechanical processes in a remodelled bone tissue depend on the dominant force and moment effects or on the stress and strain state of the tissue. The stress (strain) tensors initiate and govern the rate of biochemical remodelling processes. The paper presented deals with fundamental stoichiometric equations of bone remodelling, kinetic equations of remodelling and rate constants of remodelling. The rates of bone remodelling depend on mechanical effects or on stress (strain) tensors. The spherical stress tensor controls the rate of biomechanical remodelling reactions, while the deviator of a stress (strain) tensor initiates biomechanical reactions. The micro-strains cause the flow of a liquid in the extra-celluar space of osteocytes and initiate the receptor activity of integrins A,B, The micro-strains of a mineralised matrix and the flow of an extra-cellular liquid result, for example in the production of prostaglandin E2 and in the subsquent resorption of a bone tissue.