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Xing J, Zhang M, Liu X, Wang C, Xu N, Xing D. Multi-material electrospinning: from methods to biomedical applications. Mater Today Bio 2023; 21:100710. [PMID: 37545561 PMCID: PMC10401296 DOI: 10.1016/j.mtbio.2023.100710] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 06/03/2023] [Accepted: 06/16/2023] [Indexed: 08/08/2023] Open
Abstract
Electrospinning as a versatile, simple, and cost-effective method to engineer a variety of micro or nanofibrous materials, has contributed to significant developments in the biomedical field. However, the traditional electrospinning of single material only can produce homogeneous fibrous assemblies with limited functional properties, which oftentimes fails to meet the ever-increasing requirements of biomedical applications. Thus, multi-material electrospinning referring to engineering two or more kinds of materials, has been recently developed to enable the fabrication of diversified complex fibrous structures with advanced performance for greatly promoting biomedical development. This review firstly gives an overview of multi-material electrospinning modalities, with a highlight on their features and accessibility for constructing different complex fibrous structures. A perspective of how multi-material electrospinning opens up new opportunities for specific biomedical applications, i.e., tissue engineering and drug delivery, is also offered.
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Affiliation(s)
- Jiyao Xing
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China
- Qingdao Cancer Institute, Qingdao, 266071, China
| | - Miao Zhang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China
- Qingdao Cancer Institute, Qingdao, 266071, China
| | - Xinlin Liu
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China
- Qingdao Cancer Institute, Qingdao, 266071, China
| | - Chao Wang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China
- Qingdao Cancer Institute, Qingdao, 266071, China
| | - Nannan Xu
- School of Computer Science and Technology, Ocean University of China, Qingdao, 266000, China
| | - Dongming Xing
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China
- Qingdao Cancer Institute, Qingdao, 266071, China
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
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2
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Gögele C, Hahn J, Schulze-Tanzil G. Anatomical Tissue Engineering of the Anterior Cruciate Ligament Entheses. Int J Mol Sci 2023; 24:ijms24119745. [PMID: 37298698 DOI: 10.3390/ijms24119745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
The firm integration of anterior cruciate ligament (ACL) grafts into bones remains the most demanding challenge in ACL reconstruction, since graft loosening means graft failure. For a functional-tissue-engineered ACL substitute to be realized in future, robust bone attachment sites (entheses) have to be re-established. The latter comprise four tissue compartments (ligament, non-calcified and calcified fibrocartilage, separated by the tidemark, bone) forming a histological and biomechanical gradient at the attachment interface between the ACL and bone. The ACL enthesis is surrounded by the synovium and exposed to the intra-articular micromilieu. This review will picture and explain the peculiarities of these synovioentheseal complexes at the femoral and tibial attachment sites based on published data. Using this, emerging tissue engineering (TE) strategies addressing them will be discussed. Several material composites (e.g., polycaprolactone and silk fibroin) and manufacturing techniques (e.g., three-dimensional-/bio-printing, electrospinning, braiding and embroidering) have been applied to create zonal cell carriers (bi- or triphasic scaffolds) mimicking the ACL enthesis tissue gradients with appropriate topological parameters for zones. Functionalized or bioactive materials (e.g., collagen, tricalcium phosphate, hydroxyapatite and bioactive glass (BG)) or growth factors (e.g., bone morphogenetic proteins [BMP]-2) have been integrated to achieve the zone-dependent differentiation of precursor cells. However, the ACL entheses comprise individual (loading history) asymmetric and polar histoarchitectures. They result from the unique biomechanical microenvironment of overlapping tensile, compressive and shear forces involved in enthesis formation, maturation and maintenance. This review should provide a road map of key parameters to be considered in future in ACL interface TE approaches.
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Affiliation(s)
- Clemens Gögele
- Institute of Anatomy and Cell Biology, Paracelsus Medical University, Nuremberg and Salzburg, Prof. Ernst Nathan Str. 1, 90419 Nuremberg, Germany
| | - Judith Hahn
- Workgroup BioEngineering, Department Materials Engineering, Institute of Polymers Materials, Leibniz-Institut für Polymerforschung Dresden e.V. (IPF), Hohe Straße 6, 01069 Dresden, Germany
| | - Gundula Schulze-Tanzil
- Institute of Anatomy and Cell Biology, Paracelsus Medical University, Nuremberg and Salzburg, Prof. Ernst Nathan Str. 1, 90419 Nuremberg, Germany
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3
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Arevalo SE, Ebenstein DM, Pruitt LA. A methodological framework for nanomechanical characterization of soft biomaterials and polymers. J Mech Behav Biomed Mater 2022; 134:105384. [DOI: 10.1016/j.jmbbm.2022.105384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/08/2022] [Accepted: 07/15/2022] [Indexed: 11/24/2022]
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Peng Y, Li X, Wu W, Ma H, Wang G, Jia S, Zheng C. Effect of Mechanical Stimulation Combined With Platelet-Rich Plasma on Healing of the Rotator Cuff in a Murine Model. Am J Sports Med 2022; 50:1358-1368. [PMID: 35188809 DOI: 10.1177/03635465211073339] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Mechanical stimulation and platelet-rich plasma (PRP) have been shown to be beneficial for healing of the bone-tendon interface (BTI), but few studies have explored the efficacy of a combination of these applications. We investigated the effect of mechanical stimulation combined with PRP on rotator cuff repair in mice. HYPOTHESIS Mechanical stimulation combined with PRP can enhance BTI healing in a murine model of rotator cuff repair. STUDY DESIGN Controlled laboratory study. METHODS A total of 160 C57BL/6 mice were used. Overall, 40 mice were used to prepare PRP, while 120 mice underwent acute supraspinatus tendon (SST) repair. The animals were randomly assigned to 4 groups: control group, mechanical stimulation group, PRP group, and mechanical stimulation combined with PRP group (combination group). At 4 and 8 weeks postoperatively, animals were sacrificed, the eyeballs were removed to collect blood, and the SST-humeral complexes were collected. Histological, biomechanical, immunological, and bone morphometric tests were performed. RESULTS Histologically, at 4 and 8 weeks after surgery, the area of the fibrocartilage layer at the BTI in the combination group was larger than in the other groups. The content and distribution of proteoglycans in this layer in the combination group were significantly greater than in the other groups. At 8 weeks postoperatively, trabecular number, and trabecular bone thickness of the subchondral bone area of interest at the BTI of the combination group were greater than those of the other groups, bone volume fraction of the combination group was greater than the control group. On biomechanical testing at 4 and 8 weeks after surgery, the failure load and ultimate strength of the SST-humeral complex in the combination group were higher than in the other groups. Enzyme-linked immunosorbent assay results showed that, at 4 weeks postoperatively, the serum concentrations of transforming growth factor beta 1 and platelet-derived growth factor (PDGF) in the combination group were significantly higher than in the other groups; at 8 weeks, the PDGF-AB concentration in the combination group was higher than in the control and mechanical stimulation groups. CONCLUSION Mechanical stimulation combined with PRP can effectively promote the early stage of healing after a rotator cuff injury. CLINICAL RELEVANCE These findings imply that mechanical stimulation combined with PRP can serve as a potential therapeutic strategy for rotator cuff healing.
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Affiliation(s)
- Yundong Peng
- College of Health Science, Wuhan Sports University, Wuhan, China
| | - Xiaomei Li
- College of Health Science, Wuhan Sports University, Wuhan, China.,Medical College, Huainan Union University, Huainan, China
| | - Wenxia Wu
- College of Health Science, Wuhan Sports University, Wuhan, China.,Department of Rehabilitation Therapy, Jinci College of Shanxi Medical University, Taiyuan, China
| | - Haozhe Ma
- College of International Education, Wuhan Sports University, Wuhan, China
| | - Guanglan Wang
- College of Health Science, Wuhan Sports University, Wuhan, China
| | - Shaohui Jia
- Hubei Provincial Collaborative Innovation Center for Exercise and Health Promotion, College of Health Science, Wuhan Sports University, Wuhan, China
| | - Cheng Zheng
- Department of Sports Medicine, Affiliated Hospital, Wuhan Sports University, Wuhan, China
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5
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SantAnna JPC, Faria RR, Assad IP, Pinheiro CCG, Aiello VD, Albuquerque-Neto C, Bortolussi R, Cestari IA, Maizato MJS, Hernandez AJ, Bueno DF, Fernandes TL. Tissue Engineering and Cell Therapy for Cartilage Repair: Preclinical Evaluation Methods. Tissue Eng Part C Methods 2022; 28:73-82. [PMID: 35107353 DOI: 10.1089/ten.tec.2021.0208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
A chondral injury is a limiting disease that can affect the quality of life and be an economic burden due to the cost of immediate treatment and loss in work productivity. If left untreated, such an injury may progress to osteoarthritis, a degenerative and debilitating joint disease characterized by pain and functional impairment. Mesenchymal stromal cells (MSCs), which have immune-modulatory properties and the ability to differentiate into chondroblasts and osteoblasts, are a predictable source for the treatment of cartilage injuries. This article presents tools to evaluate cartilage restoration by tissue engineering and cell therapy treatment in a translational and preclinical large animal model. In this controlled experimental study with 14 miniature pigs, a scaffold-free tissue engineering construct (TEC) derived from dental pulp and synovial MSCs for cartilage therapy was tested. Total thickness cartilage defects were performed in both posterior knees. The defect was left empty in one of the knees, and the other received the TEC. The tissue repair was morphologically assessed by magnetic resonance imaging (MRI) using the three-dimensional double echo steady-state (3D-DESS) sequence, and compositional assessment was carried out based on the T2 mapping technique. The osteochondral specimens were fixed for histopathology, decalcified, subjected to standard histological processing, sectioned, and stained with hematoxylin and eosin. The sections stained for immunohistochemical detection of collagen types were digested with pepsin and chondroitinase and incubated with antibodies against them. The mechanical evaluation involved analysis of Young's modulus of the cartilage samples based on the indentation and maximum compression test. In addition, a finite element model was used to simulate and characterize properties of the osteochondral block. At 6 months after surgery, there were no complications with the animals and the MRI, histological, immunohistochemical, and biomechanical evaluations proved to be effective and qualified to differentiate good quality chondral repair from inadequate repair tissue. The proposed methods were feasible and capable to properly evaluate the defect filled with TEC containing stromal cells after 6 months of follow-up in a large animal model for articular cartilage restoration. Impact Statement Articular chondral injuries are prevalent and represent an economic burden due to the cost of treatment. The engineering of cartilage tissue can promote the repair of chondral injuries and is dependent on selecting appropriate cells and biocompatible frameworks. In this article, methods for evaluation of a scaffold-free cell delivery system made from mesenchymal stromal cells were present in a translational study that allows further clinical safety and efficacy trials.
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Affiliation(s)
- João P C SantAnna
- Grupo de Medicina do Esporte, Instituto de Ortopedia e Traumatologia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Rafaella R Faria
- Instituto de Ortopedia e Traumatologia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Isabella P Assad
- Instituto de Ortopedia e Traumatologia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | | | - Vera D Aiello
- Laboratório de Patologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo, Brazil
| | - Cyro Albuquerque-Neto
- Department of Mechanical Engineering, Centro Universitário da FEI, São Paulo, Brazil
| | - Roberto Bortolussi
- Department of Mechanical Engineering, Centro Universitário da FEI, São Paulo, Brazil
| | - Idágene A Cestari
- Laboratório de Investigação Médica em Bioengenharia, Instituto do Coração, Hospital das Clinicas, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Marina J S Maizato
- Laboratório de Investigação Médica em Bioengenharia, Instituto do Coração, Hospital das Clinicas, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Arnaldo J Hernandez
- Grupo de Medicina do Esporte, Instituto de Ortopedia e Traumatologia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | | | - Tiago L Fernandes
- Grupo de Medicina do Esporte, Instituto de Ortopedia e Traumatologia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil.,Hospital Sírio-Libanês, São Paulo, Brazil
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6
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Eckstein KN, Thomas SM, Scott AK, Neu CP, Payne KA, Ferguson VL. The heterogeneous mechanical properties of adolescent growth plate cartilage: A study in rabbit. J Mech Behav Biomed Mater 2022; 128:105102. [PMID: 35203020 PMCID: PMC9047008 DOI: 10.1016/j.jmbbm.2022.105102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 01/08/2022] [Accepted: 01/21/2022] [Indexed: 01/01/2023]
Abstract
The growth plate is a cartilaginous tissue that functions to lengthen bones in children. When fractured, however, the growth plate can lose this critical function. Our understanding of growth plate fracture and mechanobiology is currently hindered by sparse information on the growth plate's microscale spatial gradients in mechanical properties. In this study, we performed microindentation across the proximal tibia growth plate of 9-week-old New Zealand White rabbits (n = 15) to characterize spatial variations in mechanical properties using linear elastic and nonlinear poroelastic material models. Mean indentation results for Hertz reduced modulus ranged from 380 to 690 kPa, with a peak in the upper hypertrophic zone and significant differences (p < 0.05) between neighboring zones. Using a subset of these animals (n = 7), we characterized zonal structure and extracellular matrix content of the growth plate through confocal fluorescent microscopy and Raman spectroscopy mapping. Comparison between mechanical properties and matrix content across the growth plate showed that proteoglycan content correlated with compressive modulus. This study is the first to measure poroelastic mechanical properties from microindentation across growth plate cartilage and to discern differing mechanical properties between the upper and lower hypertrophic zones. This latter finding may explain the location of typical growth plate fractures. The spatial variation in our reported mechanical properties emphasize the heterogeneous structure of the growth plate which is important to inform future regenerative implant design and mechanobiological models.
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Jiang X, Wojtkiewicz M, Patwardhan C, Greer S, Kong Y, Kuss M, Huang X, Liao J, Lu Y, Dudley A, Gundry RL, Fuchs M, Streubel P, Duan B. The effects of maturation and aging on the rotator cuff tendon-to-bone interface. FASEB J 2021; 35:e22066. [PMID: 34822203 DOI: 10.1096/fj.202101484r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/29/2021] [Accepted: 11/10/2021] [Indexed: 12/19/2022]
Abstract
Rotator cuff tendon injuries often occur at the tendon-to-bone interface (i.e., enthesis) area, with a high prevalence for the elderly population, but the underlying reason for this phenomenon is still unknown. The objective of this study is to identify the histological, molecular, and biomechanical alterations of the rotator cuff enthesis with maturation and aging in a mouse model. Four different age groups of mice (newborn, young, adult, and old) were studied. Striking variations of the entheses were observed between the newborn and other matured groups, with collagen content, proteoglycan deposition, collagen fiber dispersion was significantly higher in the newborn group. The compositional and histological features of young, adult, and old groups did not show significant differences, except having increased proteoglycan deposition and thinner collagen fibers at the insertion sites in the old group. Nanoindentation testing showed that the old group had a smaller compressive modulus at the insertion site when compared with other groups. However, tensile mechanical testing reported that the old group demonstrated a significantly higher failure stress when compared with the young and adult groups. The proteomics analysis detected dramatic differences in protein content between newborn and young groups but minor changes among young, adult, and old groups. These results demonstrated: (1) the significant alterations of the enthesis composition and structure occur from the newborn to the young time period; (2) the increased risk of rotator cuff tendon injuries in the elderly population is not solely because of old age alone in the rodent model.
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Affiliation(s)
- Xiping Jiang
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Division of Cardiology, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Molecular Genetics and Cell Biology Program, Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Melinda Wojtkiewicz
- CardiOmics Program, Center for Heart and Vascular Research, Division of Cardiovascular Medicine, and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Chinmay Patwardhan
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, USA
| | - Sydney Greer
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Molecular Genetics and Cell Biology Program, Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Yunfan Kong
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Mitchell Kuss
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Xi Huang
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Jun Liao
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, USA
| | - Yongfeng Lu
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Andrew Dudley
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Molecular Genetics and Cell Biology Program, Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Rebekah L Gundry
- CardiOmics Program, Center for Heart and Vascular Research, Division of Cardiovascular Medicine, and Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Matthias Fuchs
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Philipp Streubel
- Department of Orthopedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Bin Duan
- Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Division of Cardiology, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Department of Surgery, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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8
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Pitta Kruize C, Panahkhahi S, Putra NE, Diaz-Payno P, van Osch G, Zadpoor AA, Mirzaali MJ. Biomimetic Approaches for the Design and Fabrication of Bone-to-Soft Tissue Interfaces. ACS Biomater Sci Eng 2021. [PMID: 34784181 DOI: 10.1021/acsbiomaterials.1c00620] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone-to-soft tissue interfaces are responsible for transferring loads between tissues with significantly dissimilar material properties. The examples of connective soft tissues are ligaments, tendons, and cartilages. Such natural tissue interfaces have unique microstructural properties and characteristics which avoid the abrupt transitions between two tissues and prevent formation of stress concentration at their connections. Here, we review some of the important characteristics of these natural interfaces. The native bone-to-soft tissue interfaces consist of several hierarchical levels which are formed in a highly specialized anisotropic fashion and are composed of different types of heterogeneously distributed cells. The characteristics of a natural interface can rely on two main design principles, namely by changing the local microarchitectural features (e.g., complex cell arrangements, and introducing interlocking mechanisms at the interfaces through various geometrical designs) and changing the local chemical compositions (e.g., a smooth and gradual transition in the level of mineralization). Implementing such design principles appears to be a promising approach that can be used in the design, reconstruction, and regeneration of engineered biomimetic tissue interfaces. Furthermore, prominent fabrication techniques such as additive manufacturing (AM) including 3D printing and electrospinning can be used to ease these implementation processes. Biomimetic interfaces have several biological applications, for example, to create synthetic scaffolds for osteochondral tissue repair.
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Affiliation(s)
- Carlos Pitta Kruize
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Sara Panahkhahi
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Niko Eka Putra
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Pedro Diaz-Payno
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Gerjo van Osch
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Amir A Zadpoor
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Mohammad J Mirzaali
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
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9
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Tits A, Ruffoni D. Joining soft tissues to bone: Insights from modeling and simulations. Bone Rep 2021; 14:100742. [PMID: 34150954 PMCID: PMC8190669 DOI: 10.1016/j.bonr.2020.100742] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/14/2020] [Accepted: 12/18/2020] [Indexed: 01/16/2023] Open
Abstract
Entheses are complex multi-tissue regions of the musculoskeletal system serving the challenging task of connecting highly dissimilar materials such as the compliant tendon to the much stiffer bone, over a very small region. The first aim of this review is to highlight mathematical and computational models that have been developed to investigate the many attachment strategies present at entheses at different length scales. Entheses are also relevant in the medical context due to the high prevalence of orthopedic injuries requiring the reattachment of tendons or ligaments to bone, which are associated with a rather poor long-term clinical outcome. The second aim of the review is to report on the computational works analyzing the whole tendon to bone complex as well as targeting orthopedic relevant issues. Modeling approaches have provided important insights on anchoring mechanisms and surgical repair strategies, that would not have been revealed with experiments alone. We intend to demonstrate the necessity of including, in future models, an enriched description of enthesis biomechanical behavior in order to unravel additional mechanical cues underlying the development, the functioning and the maintaining of such a complex biological interface as well as to enhance the development of novel biomimetic adhesive, attachment procedures or tissue engineered implants.
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Affiliation(s)
- Alexandra Tits
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium
| | - Davide Ruffoni
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium
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10
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Zorzetto L, Andena L, Briatico-Vangosa F, De Noni L, Thomassin JM, Jérôme C, Grossman Q, Mertens A, Weinkamer R, Rink M, Ruffoni D. Properties and role of interfaces in multimaterial 3D printed composites. Sci Rep 2020; 10:22285. [PMID: 33335195 PMCID: PMC7747733 DOI: 10.1038/s41598-020-79230-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 11/25/2020] [Indexed: 12/13/2022] Open
Abstract
In polyjet printing photopolymer droplets are deposited on a build tray, leveled off by a roller and cured by UV light. This technique is attractive to fabricate heterogeneous architectures combining compliant and stiff constituents. Considering the layer-by-layer nature, interfaces between different photopolymers can be formed either before or after UV curing. We analyzed the properties of interfaces in 3D printed composites combining experiments with computer simulations. To investigate photopolymer blending, we characterized the mechanical properties of the so-called digital materials, obtained by mixing compliant and stiff voxels according to different volume fractions. We then used nanoindentation to measure the spatial variation in mechanical properties across bimaterial interfaces at the micrometer level. Finally, to characterize the impact of finite-size interfaces, we fabricated and tested composites having compliant and stiff layers alternating along different directions. We found that interfaces formed by deposition after curing were sharp whereas those formed before curing showed blending of the two materials over a length scale bigger than individual droplet size. We found structural and functional differences of the layered composites depending on the printing orientation and corresponding interface characteristics, which influenced deformation mechanisms. With the wide dissemination of 3D printing techniques, our results should be considered in the development of architectured materials with tailored interfaces between building blocks.
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Affiliation(s)
- Laura Zorzetto
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Quartier Polytech 1, 4000, Liège, Belgium
| | - Luca Andena
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "G. Natta", Politecnico Di Milano, Milan, Italy
| | | | - Lorenzo De Noni
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "G. Natta", Politecnico Di Milano, Milan, Italy
| | - Jean-Michel Thomassin
- Center for Education and Research on Macromolecules, University of Liège, Liège, Belgium
| | - Christine Jérôme
- Center for Education and Research on Macromolecules, University of Liège, Liège, Belgium
| | - Quentin Grossman
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Quartier Polytech 1, 4000, Liège, Belgium
| | - Anne Mertens
- Metallic Materials Science Unit, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium
| | - Richard Weinkamer
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Marta Rink
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "G. Natta", Politecnico Di Milano, Milan, Italy
| | - Davide Ruffoni
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Quartier Polytech 1, 4000, Liège, Belgium.
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11
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Liu Z, Ramakrishna S, Liu X. Electrospinning and emerging healthcare and medicine possibilities. APL Bioeng 2020; 4:030901. [PMID: 32695956 PMCID: PMC7365682 DOI: 10.1063/5.0012309] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/01/2020] [Indexed: 01/06/2023] Open
Abstract
Electrospinning forms fibers from either an electrically charged polymer solution or polymer melt. Over the past decades, it has become a simple and versatile method for nanofiber production. Hence, it has been explored in many different applications. Commonly used electrospinning assembles fibers from polymer solutions in various solvents, known as solution electrospinning, while melt and near-field electrospinning techniques enhance the versatility of electrospinning. Adaption of additive manufacturing strategy to electrospinning permits precise fiber deposition and predefining pattern construction. This manuscript critically presents the potential of electrospun nanofibers in healthcare applications. Research community drew impetus from the similarity of electrospun nanofibers to the morphology and mechanical properties of fibrous extracellular matrices (ECM) of natural human tissues. Electrospun nanofibrous scaffolds act as ECM analogs for specific tissue cells, stem cells, and tumor cells to realize tissue regeneration, stem cell differentiation, and in vitro tumor model construction. The large surface-to-volume ratio of electrospun nanofibers offers a considerable number of bioactive agents binding sites, which makes it a promising candidate for a number of biomedical applications. The applications of electrospinning in regenerative medicine, tissue engineering, controlled drug delivery, biosensors, and cancer diagnosis are elaborated. Electrospun nanofiber incorporations in medical device coating, in vitro 3D cancer model, and filtration membrane are also discussed.
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Affiliation(s)
- Ziqian Liu
- Department of Mechanical, Materials and Manufacturing, The University of Nottingham Ningbo China, Ningbo 315100, China
| | - Seeram Ramakrishna
- Center for Nanofibers and Nanotechnology, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore
| | - Xiaoling Liu
- Department of Mechanical, Materials and Manufacturing, The University of Nottingham Ningbo China, Ningbo 315100, China
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Ashinsky BG, Bonnevie ED, Mandalapu SA, Pickup S, Wang C, Han L, Mauck RL, Smith HE, Gullbrand SE. Intervertebral Disc Degeneration Is Associated With Aberrant Endplate Remodeling and Reduced Small Molecule Transport. J Bone Miner Res 2020; 35:1572-1581. [PMID: 32176817 PMCID: PMC8207249 DOI: 10.1002/jbmr.4009] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 02/18/2020] [Accepted: 03/10/2020] [Indexed: 12/14/2022]
Abstract
The intervertebral disc is the largest avascular structure in the body, and cells within the disc rely on diffusive transport via vasculature located within the vertebral endplate to receive nutrients, eliminate waste products, and maintain disc health. However, the mechanisms by which small molecule transport into the disc occurs in vivo and how these parameters change with disc degeneration remain understudied. Here, we utilize an in vivo rabbit puncture disc degeneration model to study these interactions and provide evidence that remodeling of the endplate adjacent to the disc occurs concomitant with degeneration. Our results identify significant increases in endplate bone volume fraction, increases in microscale stiffness of the soft tissue interfaces between the disc and vertebral bone, and reductions in endplate vascularity and small molecule transport into the disc as a function of degenerative state. A neural network model identified changes in diffusion into the disc as the most significant predictor of disc degeneration. These findings support the critical role of trans-endplate transport in disease progression and will improve patient selection to direct appropriate surgical intervention and inform new therapeutic approaches to improve disc health. © 2020 American Society for Bone and Mineral Research. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.
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Affiliation(s)
- Beth G Ashinsky
- Translational Musculoskeletal Research Center, Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
- School of Biomedical Engineering Science and Health Systems, Drexel University, Philadelphia, PA, USA
| | - Edward D Bonnevie
- Translational Musculoskeletal Research Center, Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Sai A Mandalapu
- Translational Musculoskeletal Research Center, Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Stephen Pickup
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Chao Wang
- School of Biomedical Engineering Science and Health Systems, Drexel University, Philadelphia, PA, USA
| | - Lin Han
- School of Biomedical Engineering Science and Health Systems, Drexel University, Philadelphia, PA, USA
| | - Robert L Mauck
- Translational Musculoskeletal Research Center, Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Harvey E Smith
- Translational Musculoskeletal Research Center, Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Sarah E Gullbrand
- Translational Musculoskeletal Research Center, Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
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Nanoindentation: An advanced procedure to investigate osteochondral engineered tissues. J Mech Behav Biomed Mater 2019; 96:79-87. [DOI: 10.1016/j.jmbbm.2019.04.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 03/25/2019] [Accepted: 04/21/2019] [Indexed: 11/17/2022]
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Luo W, Liu H, Wang C, Qin Y, Liu Q, Wang J. Bioprinting of Human Musculoskeletal Interface. ADVANCED ENGINEERING MATERIALS 2019; 21:1900019. [DOI: 10.1002/adem.201900019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Indexed: 07/28/2023]
Affiliation(s)
- Wenbin Luo
- Department of OrthopedicsThe Second Hospital of Jilin UniversityChangchun130041P. R. China
| | - He Liu
- Department of OrthopedicsThe Second Hospital of Jilin UniversityChangchun130041P. R. China
| | - Chenyu Wang
- Department of OrthopedicsThe Second Hospital of Jilin UniversityChangchun130041P. R. China
- Hallym University1Hallymdaehak‐gilChuncheonGangwon‐do200‐702Korea
| | - Yanguo Qin
- Department of OrthopedicsThe Second Hospital of Jilin UniversityChangchun130041P. R. China
| | - Qingping Liu
- Key Laboratory of Bionic Engineering (Ministry of Education)Jilin UniversityChangchun130022P. R. China
| | - Jincheng Wang
- Department of OrthopedicsThe Second Hospital of Jilin UniversityChangchun130041P. R. China
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Abstract
Electrospinning is a versatile and viable technique for generating ultrathin fibers. Remarkable progress has been made with regard to the development of electrospinning methods and engineering of electrospun nanofibers to suit or enable various applications. We aim to provide a comprehensive overview of electrospinning, including the principle, methods, materials, and applications. We begin with a brief introduction to the early history of electrospinning, followed by discussion of its principle and typical apparatus. We then discuss its renaissance over the past two decades as a powerful technology for the production of nanofibers with diversified compositions, structures, and properties. Afterward, we discuss the applications of electrospun nanofibers, including their use as "smart" mats, filtration membranes, catalytic supports, energy harvesting/conversion/storage components, and photonic and electronic devices, as well as biomedical scaffolds. We highlight the most relevant and recent advances related to the applications of electrospun nanofibers by focusing on the most representative examples. We also offer perspectives on the challenges, opportunities, and new directions for future development. At the end, we discuss approaches to the scale-up production of electrospun nanofibers and briefly discuss various types of commercial products based on electrospun nanofibers that have found widespread use in our everyday life.
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Affiliation(s)
- Jiajia Xue
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
| | - Tong Wu
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
| | - Yunqian Dai
- School of Chemistry and Chemical Engineering, Southeast University, Nanjing, Jiangsu 211189, People’s Republic of China
| | - Younan Xia
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
- School of Chemistry and Biochemistry, School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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Stewart DC, Berrie D, Li J, Liu X, Rickerson C, Mkoji D, Iqbal A, Tan S, Doty AL, Glover SC, Simmons CS. Quantitative assessment of intestinal stiffness and associations with fibrosis in human inflammatory bowel disease. PLoS One 2018; 13:e0200377. [PMID: 29995938 PMCID: PMC6040714 DOI: 10.1371/journal.pone.0200377] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 06/25/2018] [Indexed: 01/05/2023] Open
Abstract
Inflammatory bowel disease (IBD) continues to increase in prevalence in industrialized countries. Major complications of IBD include formation of fibrotic strictures, fistulas, reduced absorptive function, cancer risk, and the need for surgery. In other chronic gastrointestinal disease models, stiffness has been shown to precede fibrosis; therefore, stiffness may be a reasonable indicator of progression toward stricture formation in IBD patients. Herein, we seek to quantify tissue stiffness and characterize fibrosis in patients with IBD and to compare mechanical properties of unaffected human tissue to common animal species used for IBD studies. Inflamed and unaffected tissue from IBD patients and unaffected tissue from mice, pigs, and cows were indented using a custom device to determine the effective stiffness. Histology was performed on matched tissues, and total RNA was isolated from IBD tissue samples and used for gene expression analysis of pro-fibrotic genes. We observed an increase in the effective stiffness (steady-state modulus, SSM) (p < 0.0001) and increased expression of the collagen type I gene (COL1A1, p = 0.01) in inflamed tissue compared to unaffected areas in our IBD patient cohort. We also found that increased staining of collagen fibers in submucosa positively correlated with SSM (p = 0.093). We determined that unaffected animal bowel stiffness is significantly greater than similar human tissues, suggesting additional limitations on animal models for translational investigations regarding stiffness-related hypotheses. Taken together, our data support development of tools for evaluation of bowel stiffness in IBD patients for prognostic applications that may enable more accurate prediction of those who will develop fibrosis and more precise prescription of aggressive therapies.
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Affiliation(s)
- Daniel C. Stewart
- J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States of America
| | - Dalton Berrie
- J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States of America
- Division of Gastroenterology, Hepatology and Nutrition, College of Medicine, University of Florida, Gainesville, FL, United States of America
| | - Jian Li
- Division of Gastroenterology, Hepatology and Nutrition, College of Medicine, University of Florida, Gainesville, FL, United States of America
| | - Xinyue Liu
- Department of Pharmaceutical Outcomes and Policy, College of Pharmacy, University of Florida, Gainesville, FL, United States of America
| | - Cooper Rickerson
- J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States of America
| | - David Mkoji
- Department of Mechanical and Aerospace Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States of America
| | - Atif Iqbal
- Department of Surgery, College of Medicine, University of Florida, Gainesville, FL, United States of America
| | - Sanda Tan
- Department of Surgery, College of Medicine, University of Florida, Gainesville, FL, United States of America
| | - Andria L. Doty
- Division of Gastroenterology, Hepatology and Nutrition, College of Medicine, University of Florida, Gainesville, FL, United States of America
| | - Sarah C. Glover
- Division of Gastroenterology, Hepatology and Nutrition, College of Medicine, University of Florida, Gainesville, FL, United States of America
| | - Chelsey S. Simmons
- J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States of America
- Department of Mechanical and Aerospace Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, FL, United States of America
- Division of Cardiovascular Medicine, College of Medicine, University of Florida, Gainesville, FL, United States of America
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Antons J, Marascio MGM, Nohava J, Martin R, Applegate LA, Bourban PE, Pioletti DP. Zone-dependent mechanical properties of human articular cartilage obtained by indentation measurements. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2018; 29:57. [PMID: 29728770 DOI: 10.1007/s10856-018-6066-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 04/18/2018] [Indexed: 05/22/2023]
Abstract
Emerging 3D printing technology permits innovative approaches to manufacture cartilage scaffolds associated with layer-by-layer mechanical property adaptation. However, information about gradients of mechanical properties in human articular cartilage is limited. In this study, we quantified a zone-dependent change of local elastic modulus of human femoral condyle cartilage by using an instrumented indentation technique. From the cartilage superficial zone towards the calcified layer, a gradient of elastic modulus values between 0.020 ± 0.003 MPa and 6.44 ± 1.02 MPa was measured. To validate the tissue quality, the histological tissue composition was visualized by glycosaminoglycan and collagen staining. This work aims to introduce a new protocol to investigate the zone-dependent mechanical properties of graded structures, such as human articular cartilage. From this knowledge, better cartilage repair strategies could be tailored in the future.
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Affiliation(s)
- J Antons
- Laboratory of Biomechanical Orthopedics, Institute of Bioengineering, EPFL, Lausanne, Switzerland
| | - M G M Marascio
- Laboratory of Processing of Advanced Composites, Institute of Material Science, EPFL, Lausanne, Switzerland
| | | | - R Martin
- Department of Musculoskeletal Medicine, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - L A Applegate
- Regenerative Therapy Unit, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - P E Bourban
- Laboratory of Processing of Advanced Composites, Institute of Material Science, EPFL, Lausanne, Switzerland
| | - D P Pioletti
- Laboratory of Biomechanical Orthopedics, Institute of Bioengineering, EPFL, Lausanne, Switzerland.
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Marcus MA, Amini S, Stifler CA, Sun CY, Tamura N, Bechtel HA, Parkinson DY, Barnard HS, Zhang XXX, Chua JQI, Miserez A, Gilbert PUPA. Parrotfish Teeth: Stiff Biominerals Whose Microstructure Makes Them Tough and Abrasion-Resistant To Bite Stony Corals. ACS NANO 2017; 11:11856-11865. [PMID: 29053258 DOI: 10.1021/acsnano.7b05044] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Parrotfish (Scaridae) feed by biting stony corals. To investigate how their teeth endure the associated contact stresses, we examine the chemical composition, nano- and microscale structure, and the mechanical properties of the steephead parrotfish Chlorurus microrhinos tooth. Its enameloid is a fluorapatite (Ca5(PO4)3F) biomineral with outstanding mechanical characteristics: the mean elastic modulus is 124 GPa, and the mean hardness near the biting surface is 7.3 GPa, making this one of the stiffest and hardest biominerals measured; the mean indentation yield strength is above 6 GPa, and the mean fracture toughness is ∼2.5 MPa·m1/2, relatively high for a highly mineralized material. This combination of properties results in high abrasion resistance. Fluorapatite X-ray absorption spectroscopy exhibits linear dichroism at the Ca L-edge, an effect that makes peak intensities vary with crystal orientation, under linearly polarized X-ray illumination. This observation enables polarization-dependent imaging contrast mapping of apatite, a method to quantitatively measure and display nanocrystal orientations in large, pristine arrays of nano- and microcrystalline structures. Parrotfish enameloid consists of 100 nm-wide, microns long crystals co-oriented and assembled into bundles interwoven as the warp and the weave in fabric and therefore termed fibers here. These fibers gradually decrease in average diameter from 5 μm at the back to 2 μm at the tip of the tooth. Intriguingly, this size decrease is spatially correlated with an increase in hardness.
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Affiliation(s)
- Matthew A Marcus
- Advanced Light Source, Lawrence Berkeley Laboratory , Berkeley, California 94720, United States
| | - Shahrouz Amini
- Biological and Biomimetic Material Laboratory, School of Materials Science and Engineering, Nanyang Technological University , 637553 Singapore
| | - Cayla A Stifler
- Department of Physics, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Chang-Yu Sun
- Department of Physics, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Nobumichi Tamura
- Advanced Light Source, Lawrence Berkeley Laboratory , Berkeley, California 94720, United States
| | - Hans A Bechtel
- Advanced Light Source, Lawrence Berkeley Laboratory , Berkeley, California 94720, United States
| | - Dilworth Y Parkinson
- Advanced Light Source, Lawrence Berkeley Laboratory , Berkeley, California 94720, United States
| | - Harold S Barnard
- Advanced Light Source, Lawrence Berkeley Laboratory , Berkeley, California 94720, United States
| | - Xiyue X X Zhang
- Advanced Light Source, Lawrence Berkeley Laboratory , Berkeley, California 94720, United States
| | - J Q Isaiah Chua
- Biological and Biomimetic Material Laboratory, School of Materials Science and Engineering, Nanyang Technological University , 637553 Singapore
| | - Ali Miserez
- Biological and Biomimetic Material Laboratory, School of Materials Science and Engineering, Nanyang Technological University , 637553 Singapore
- School of Biological Sciences, Nanyang Technological University , 637551 Singapore
| | - Pupa U P A Gilbert
- Department of Physics, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
- Departments of Chemistry, Geoscience, Materials Science Program, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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