Details of a Researcher - Takano, Naoki

Papers - Takano, Naoki

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Biomechanics of Jaw Bone Considering Structural Properties of Trabecular Bone

Satoru Matsunaga, Naoki Takano, Yuichi Tamatsu, Shinichi Abe and Yoshinobu Ide

Journal of Oral Biosciences (Journal of Oral Biosciences) 53 ( 2 ) 143/147 - 147 2011

Research paper (scientific journal), Joint Work, ISSN 13490079

Mechanical stress is an important factor in bone homeostasis, which is impossible to visualize and therefore difficult to evaluate. Biomechanical analysis based on the three-dimensional finite element method (3D FEM) has become more accurate, and it is now possible to analyze load transfer pathways taking into consideration the trabecular structures. It has even become feasible to develop treatment plans based on mechanical factors using image data acquired from the patient. This review describes the usefulness and prospects of biomechanical analysis of the jaw bones, specifically finite element analysis (FEA) based upon the consideration of internal microstructures.

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Biomechanical Role of Peri-Implant Cancellous Bone Architecture

Satoru Matsunaga ,Yoshitaka Shirakura, Takashi Ohashi, Ken Nakahara, Yuichi Tamatsu, Naoki Takano and Yoshinobu Ide

The International Journal of Prosthodontics (International Journal of Prosthodontics) 23 ( 4 ) 333-338 - 338 2010.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 08932174

Purpose: The aim of this study was to investigate the biomechanical role of trabecular bone around dental implants in the mandible. Materials and Methods: The model in this study was made using micro-computed tomography data taken from a cadaver in whom endosseous implants had been in place for 15 years prior to death. Morphologic analysis and three-dimensional (3D) finite element analysis were performed to calculate the peri-implant loading path of the model in which the trabecular structure was accurately simulated. Results: As seen through multiscale analysis using the homogenization method, the trabecular bone architecture around implants was isotropic for the most part. Also, 3D finite element analysis showed that compressive stresses oblique to the implant axis were transmitted to the lower constrained surface; tensile stresses oblique to the implant axis were transmitted to the upper constrained surface, and they intersected each other with vertical loading. The highest stress in cancellous bone was observed on perpendicular loading, and stress produced in trabeculae decreased approaching horizontal loading. Conclusion: Cancellous bone architecture around the implant was generally isotropic. 3D finite element analysis showed that cancellous bone trabeculae around implants dispersed stress by forming load transfer paths. The results suggest that trabecular bone plays a major role in supporting functional pressure exerted via the implant. © 2010 by Quintessence Publishing Co Inc.

マルチスケール応力解析によるヒト椎体海綿骨の力学的評価

TAKANO Naoki

日本骨形態計測学会雑誌 20 ( 1 ) S100-S107 2010.05

Research paper (scientific journal), Joint Work, Accepted

Effect of Tension and Curvature of Skin on Insertion Characteristics of Microneedle Array

Hiroto Tachikawa, Naoki Takano, Kazuaki Nishiyabu Norisisa Miki and Yoshimichi Ami

Journal of Solid Mechanics and Materials Engineering 4 ( 3 ) 470-480 2010.03

Research paper (scientific journal), Joint Work, Accepted

Structural Strength Prediction for Porous Titanium Based on Micro-stress Concentration by Micro-CT Image-based Multiscale Simulation

Naoki Takano, Ken Fukasawa and Kazuaki Nishiyabu

International Jouranal of Mechanical Sciences (International Journal of Mechanical Sciences) 52 ( 52 ) 229-235 - 235 2010.01

Research paper (scientific journal), Joint Work, ISSN 00207403

For the design of porous titanium component, differently from its use as functional materials, structural strength prediction algorithm is proposed based on the micro-stress concentration analyzed by the multiscale simulation. The modeling of real microstructure is carried out by the image-based technique with X-ray micro-CT. The multiscale computational method consists of asymptotic homogenization and finite element mesh superposition (FEMS) techniques. A criterion is proposed to predict the nonlinearity initiation point in the load and displacement curve by means of micro-stress distribution expressed by histogram. Only the constituent's yield strength is referred regardless of the microscopic morphology. The originality of this paper lies in the validation of the homogenization process, the modeling guideline of micro-mesh superposition onto macro-mesh in FEMS, and the strength prediction algorithm. L-shaped components with different pore diameter were discussed in both experiment and simulation. © 2009 Elsevier Ltd. All rights reserved.

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Biomechanical Role of Peri-implant Trabecular Structures during Vertical Loading

Takashi Ohashi, Satoru Matsunaga ,Ken Nakahara, Shinichi Abe, Yoshinobu Ida, Yuichi Yamatsu and Naoki Takano

Clinical Oral Investigation (Clinical Oral Investigations) 14 ( 5 ) 507-513 - 513 2009.08

Research paper (scientific journal), Joint Work, ISSN 14326981

The aim of this study was to identify the load transfer paths in cortical bone and trabecular structure of cancellous bone in the jawbones for loads from endosseous implants. Maxillae were resected from beagle dogs 6 months after implant surgery and imaged using micro-computed tomography (micro-CT). A three-dimensional structure was produced based on the CT data and peri-implant trabecular structure was observed. Load transfer paths were analyzed from the results of three-dimensional finite element analysis. Furthermore, buffer actions in bone trabeculae when strain increased during stress analysis and when loads were applied were observed. Peri-implant bone trabeculae were seen extending into the upper and lower cortical bone from the fixture. The direction of bone trabecular alignment corresponded with the load transfer paths. In addition, analysis with increased strain confirmed that trabecular structures could serve as load buffers. These results suggest that bone trabeculae supporting load transfer from implants undergo remodeling. © 2009 Springer-Verlag.

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Creative Design with Multi-objective Topology Optimization

Chen Jian Ken Lee, Naoki Takano

Transactions of Japan Society for Computational Engineering and Science, Vol.2009 Paper No.20090011 2009.07

Research paper (scientific journal), Joint Work

Reduction of Finite Element Mesh and Model Order for Fast Dynamic Analysis of Global/Local Problem

Atsushi Sando, Naoki Takano, Mitsuteru Asai, Toshiyuki Toriyama, Shoji Kido and Jan.G.Korvonk

Jurnal of Solid Mechanics and Materials Engineering (JSME) 3 ( 3 ) 572-583 2009.03

Research paper (scientific journal), Joint Work

Insertion Testing of Polyethylene Glycol Microneedle Array into Cultured Human Skin with Biaxial Tension

Naoki Takano, Hiroto Tachiawa, Takaya Miyano, and Kazuaki Nishiyabu

Journal of Solid Mechanics and Materials Engineering (JSME) 3 ( 3 ) 604-612 2009.03

Research paper (scientific journal), Joint Work

Adjoint Variable Method for Multi-objective Sizing and Shape Optimization

C. J. K. Lee, W. Furuya, M. Tanaka and N. Takano

Journal of Computational Science and Technology (JSME) 2009

Research paper (scientific journal), Joint Work, Accepted

Removing Void Elements for Structural Level Set Topology Optimizaiton

Chen Jian Ken Lee, Zhiqian Zhang, Naoki Takano

Journal of Computational Science and Technology (JSME) 3 ( 1 ) 385-395 2009

Research paper (scientific journal), Joint Work, Accepted

Three-dimensional morphology analysis and finite element modeling of nano particle dispersed materials

Takano N., Asai M., Kouda T., Hashimoto K.

Zairyo/Journal of the Society of Materials Science, Japan (Zairyo/Journal of the Society of Materials Science, Japan) 57 ( 5 ) 423 - 429 2008.05

ISSN 05145163

This paper presents a three-dimensional morphology analysis technique by means of TEM tomography and finite element modeling of nano particle dispersed composite materials. The target material system in this paper is natural rubber reinforced by carbon black (CB) nano-particles. The average diameter of CB ranges from 30 to 122nm. The main feature of this paper is that the interphase named sticky hard layer between CB and free rubber is considered in detail. The Young's modulus was estimated by pulse nuclear magnetic resonance (NMR), and the thickness was obtained by measuring the volume content and moreover considering the agglomeration of CB nano-particles. The Young's modulus of the sticky hard layer was 5 to 30 times larger than that of free rubber. The relative thickness of the sticky hard layer divided by the CB diameter was found to be very influential on the overall properties of the composites, because its percolation forms the load carrying path in the composites as demonstrated by finite element analysis. These results have been supposed to be the major reason to explain the nano-particle size effect on the overall properties, which have never been understood by the classical rule of mixture. © 2008 The Society of Materials Science.

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Assessment of bone quality. Biomechanics simulation for bone quality evaluation

Takano N., Nakano T.

Clinical calcium (Clinical calcium) 18 ( 3 ) 347 - 353 2008.03

ISSN 09175857

The outline of the novel multiscale biomechanics simulation is described, which bridges nanoscale, microscale and macroscale by considering both the three-dimensional network architecture of trabecular bone captured by means of micro-CT and the biological apatite crystallite orientation. The article covers the fundamentals of the stress analysis and the muliscale computational method including some important topics in the engineering field. And finally, the simulation of trabecular bone of human vertebra is presented.

Two-dimensional quantitative analysis of preferential alignment of biological apatite c-axis for isolated human trabecular bone using microbeam X-ray diffractometer with a transmission optical system

Miyabe S., Nakano T., Ishimoto T., Takano N., Adachi T., Iwaki H., Kobayashi A., Takaoka K., Umakoshi Y.

Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals (Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals) 72 ( 1 ) 57 - 62 2008.01

ISSN 00214876

Two-dimensional quantitative analysis of microbeam X-ray diffraction (XRD) was performed using a transmission optical system to examine biological apatite (BAp) orientation in an isolated trabecula of a human fourth lumber vertebral body. The incident X-ray beam is 20 μm in diameter, which is small enough for the isolated trabecula despite a slight beam divergence of 0.2°. Integrated intensities of (002) and (310) are obtained separately by different incident angles and detector positions. Distribution of the preferential orientation of the BAp c-axis is finally calculated quantitatively as an integrated intensity ratio of (002) / (310) in a plane containing the trabecular direction. Preferential alignment of the BAp c-axis was finally determined to be perfectly parallel to the fiber direction in a rod-shaped trabecula, since accurate one-dimensional alignment is different from the alignment in the femoral cortical bone as a long bone that shows the local maximum of preferential alignment perpendicular to the longitudinal bone axis. For example, the integrated intensity ratio of (002) / (310) has a maximum value of 16 along the trabecular fiber and a minimum value of 0.09 in the perpendicular direction. Using this method, the anisotropy of BAp orientation in the trabecular bone can be quantitatively evaluated in the plane including the trabecular fiber. Thus, we successfully obtained a methodology that two-dimensionally analyzes the distribution of the BAp c-axis along all axes within a plane in a bone specimen. © 2008 The Japan Institute of Metals.

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透過型光学系を有する微小領域X線回折法によるヒト海綿骨内生体アパタイト結晶配向性の２次元定量解析

TAKANO Naoki

日本金属学会誌 72 ( 1 ) 57-62 2008

Research paper (scientific journal), Joint Work, Accepted

ナノ粒子分散材の3次元モルフォロジー分析と有限要素モデリング

TAKANO Naoki

材料 57 ( 5 ) 423-429 2008

Research paper (scientific journal), Joint Work, Accepted

骨質を考慮した椎体海綿骨の高分解能ミクロ応力解析

TAKANO Naoki

日本臨床バイオメカニクス学会誌 20 7-14 2008

Research paper (scientific journal), Joint Work, Accepted

Hydrolytic microneedles as transdermal drug delivery system

Miyano T., Miyachi T., Okanishi T., Todo H., Sugibayashi K., Uemura T., Takano N., Konishi S.

TRANSDUCERS and EUROSENSORS '07 - 4th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS and EUROSENSORS '07 - 4th International Conference on Solid-State Sensors, Actuators and Microsystems) 355 - 358 2007.12

ISSN 9781424408429

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Proposal of a new bimorph piezoelectric actuator for blood extraction pump in health monitoring system

Uetsuji Y., Nagakura H., Kawahara S., Hwang F., Tsuchiya K., Yamamoto H., Takano N., Nakamachi E.

Zairyo/Journal of the Society of Materials Science, Japan (Zairyo/Journal of the Society of Materials Science, Japan) 56 ( 5 ) 477 - 482 2007.05

ISSN 05145163

Health monitoring system equipped with blood extraction pump is one of the important problems for new medical technology to support the advanced age society. In this paper, a new piezoelectric actuator for blood extraction pump was proposed to increase volumetric change in pump. We devised the geometry of piezoelectric actuator with some slits that allows the stretching and contracting deformation in in-plane direction to create large deflection in out-of-plane direction. Focusing on a disc-type bimorph plate with some slits, the deformations under static electric load have been analyzed by finite element method with consideration of two geometric parameters, length l and width w of slits. The computational results indicated that the deformation of bimorph actuator changes from complex mode to single mode according to increase of slit length, and that single mode presents remarkable increase of deflection under surrounding-fixed condition. And then, a bimorph actuator with 4 slits l = 2.0, w = 0.5mm has been manufactured as an experiment. As a result, a developed actuator was proved to increase the deflection under dynamic electric load compared with a conventional bimorph actuator without slits. © 2007 The Society of Materials Science.

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Two-dimensional quantitative analysis of preferential alignment of BAp c-axis for isolated human trabecular bone using microbeam X-ray diffractometer with a transmission optical system

Miyabe S., Nakano T., Ishimoto T., Takano N., Adachi T., Iwaki H., Kobayashi A., Takaoka K., Umakoshi Y.

Materials Transactions (Materials Transactions) 48 ( 3 ) 343 - 347 2007.03

ISSN 13459678

Two-dimensional quantitative analysis of microbeam X-ray diffraction (XRD) was performed using a transmission optical system to examine biological apatite (BAp) orientation in an isolated trabecula of a human fourth lumber vertebral body. The incident X-ray beam is 20 μm in diameter, which is small enough for the isolated trabecula despite a slight beam divergence of 0.2°. Integrated intensities of (002) and (310) are obtained separately by different incident angles and detector positions. Distribution of the preferential orientation of the BAp c-axis is finally calculated quantitatively as an integrated intensity ratio of (002)/(310) in a plane containing the trabecular direction. Preferential alignment of the BAp c-axis was finally determined to be perfectly parallel to the fiber direction in a rod-shaped trabecula, since accurate one-dimensional alignment is different from the alignment in the femoral cortical bone as a long bone that shows the local maximum of preferential alignment perpendicular to the longitudinal bone axis. For example, the integrated intensity ratio of (002)/(310) has a maximum value of 16 along the trabecular fiber and a minimum value of 0.09 in the perpendicular direction. Using this method, the anisotropy of BAp orientation in the trabecular bone can be quantitatively evaluated in the plane including the trabecular fiber. Thus, we successfully obtained a methodology that two-dimensionally analyzes the distribution of the BAp c-axis along all axes within a plane in a bone specimen. © 2007 The Japan Institute of Metals.

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