Recent Developments in Polyurethane-Based Materials for Bone Tissue Engineering

To meet the needs of clinical medicine, bone tissue engineering is developing dynamically. Scaffolds for bone healing might be used as solid, preformed scaffolding materials, or through the injection of a solidifiable precursor into the defective tissue. There are miscellaneous biomaterials used to stimulate bone repair including ceramics, metals, naturally derived polymers, synthetic polymers, and other biocompatible substances. Combining ceramics and metals or polymers holds promise for future cures as the materials complement each other. Further research must explain the limitations of the size of the defects of each scaffold, and additionally, check the possibility of regeneration after implantation and resistance to disease. Before tissue engineering, a lot of bone defects were treated with autogenous bone grafts. Biodegradable polymers are widely applied as porous scaffolds in bone tissue engineering. The most valuable features of biodegradable polyurethanes are good biocompatibility, bioactivity, bioconductivity, and injectability. They may also be used as temporary extracellular matrix (ECM) in bone tissue healing and regeneration. Herein, the current state concerning polyurethanes in bone tissue engineering are discussed and introduced, as well as future trends.

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Conceptual design of three-dimensional scaffolds of powder-based materials for bone tissue engineering applications

Rapid Prototyping Journal ◽

10.1108/rpj-12-2013-0123 ◽

2015 ◽

Vol 21 (6) ◽

pp. 716-724 ◽

Cited By ~ 15

Author(s):

Ramakrishna Vasireddi ◽

Bikramjit Basu

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Pore Size ◽

Bone Tissue ◽

Bone Repair ◽

Three Dimensional ◽

Porous Scaffolds ◽

Content Type ◽

Pore Sizes ◽

Pore Size Distributions

Purpose – The purpose of this paper is to investigate the possibility to construct tissue-engineered bone repair scaffolds with pore size distributions using rapid prototyping techniques. Design/methodology/approach – The fabrication of porous scaffolds with complex porous architectures represents a major challenge in tissue engineering and the design aspects to mimic complex pore shape as well as spatial distribution of pore sizes of natural hard tissue remain unexplored. In this context, this work aims to evaluate the three-dimensional printing process to study its potential for scaffold fabrication as well as some innovative design of homogeneously porous or gradient porous scaffolds is described and such design has wider implication in the field of bone tissue engineering. Findings – The present work discusses biomedically relevant various design strategies with spatial/radial gradient in pore sizes as well as with different pore sizes and with different pore geometries. Originality/value – One of the important implications of the proposed novel design scheme would be the development of porous bioactive/biodegradable composites with gradient pore size, porosity, composition and with spatially distributed biochemical stimuli so that stem cells loaded into scaffolds would develop into complex tissues such as those at the bone–cartilage interface.

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Characterization and In Vitro Assessment Of Three-Dimensional Extrusion Mg-Sr Codoped SiO2-Complexed Porous Micro-Hydroxyapatite Whisker Scaffolds For Bone Tissue Engineering

10.21203/rs.3.rs-587482/v1 ◽

2021 ◽

Author(s):

Chengyong Li ◽

Tingting Yan ◽

Zhenkai Lou ◽

Zhimin Jiang ◽

Zhi Shi ◽

...

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Bone Repair ◽

Three Dimensional ◽

Chemical Properties ◽

Treatment Method ◽

Porous Scaffolds ◽

Active Elements

Abstract Background Orthopedics has made great progress with the development of medical treatment; however, large bone defects are still great challenges for orthopedic surgeons. A good bone substitute that can be obtained through bone tissue engineering may be an effective treatment method. Artificial hydroxyapatite is the main inorganic component of bones, but its applications are limited due to its fragility and lack of bone-active elements. Therefore, it is necessary to reduce its fragility and improve its biological activity. Methods In this study, we developed micro-hydroxyapatite whiskers (mHAws), which were doped with the essential trace active elements Mg2+ and Sr2+ through a low-temperature sintering technique, used silica complexes to improve the mechanical properties, and then manufactured the bionic porous scaffolds by extrusion molding and freeze-drying. Results Four types of scaffolds were obtained: mHAw-SiO2, Mg-doped mHAw-SiO2, Sr-doped mHAw-SiO2 and Mg-Sr-codoped mHAw-SiO2. These composite porous scaffolds have been suggested to have a sufficiently porous morphology with appropriate mechanical strength, are noncytotoxic, are able to support cell proliferation and spreading, and, more importantly, can promote the osteogenic differentiation of rBMSCs. Conclusion Therefore, these doped scaffolds not only have physical and chemical properties suitable for bone tissue engineering, but also have higher osteogenic bioactivity, and can be possibly serve as potential bone repair material.

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Preparation and characterization of porous hydroxyapatite/β-cyclodextrin-based polyurethane composite scaffolds for bone tissue engineering

Journal of Biomaterials Applications ◽

10.1177/0885328218797545 ◽

2018 ◽

Vol 33 (3) ◽

pp. 402-409 ◽

Cited By ~ 2

Author(s):

Jingjing Du ◽

Shuchun Gan ◽

Qihao Bian ◽

Duhan Fu ◽

Yan Wei ◽

...

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Bone Repair ◽

Cell Attachment ◽

Hexamethylene Diisocyanate ◽

Porous Scaffolds ◽

Composite Scaffolds ◽

Porous Hydroxyapatite ◽

Polyurethane Composite

In this study, novel porous scaffolds containing hydroxyapatite and β-cyclodextrin-based polyurethane were first successfully fabricated by polymerizing β-cyclodextrin with hexamethylene diisocyanate and hydroxyapatite in situ for bone tissue engineering. The physicochemical and mechanical properties as well as cytocompatibility of porous scaffolds were investigated. The results showed that polyurethane reinforced with hydroxyapatite composites had cancellous bone-like porous structure. The mechanical strength of the scaffolds increased with increasing the hydroxyapatite content in scaffolds. Synthesized scaffolds (PU1, PUHA1, PU2, and PUHA2) presented compressive strength values of 0.87 ± 0.24 MPa, 1.81 ± 0.10 MPa, 6.16 ± 0.89 MPa, and 12.95 ± 2.05 MPa, respectively. The pore size and porosity of these scaffolds were suitable for bone regeneration. Cytocompatibility of composite scaffolds was proven via favorable interactions with MC3T3-E1 cells. The addition of hydroxyapatite into CD-based polyurethane scaffolds improved cell attachment, well-spread morphology, and higher proliferation. The hydroxyapatite-polyurethane scaffolds have the potential to be applied in bone repair and regeneration.

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Conductive Scaffolds for Bone Tissue Engineering: Current State and Future Outlook

Journal of Functional Biomaterials ◽

10.3390/jfb13010001 ◽

2021 ◽

Vol 13 (1) ◽

pp. 1

Author(s):

Damion T. Dixon ◽

Cheryl T. Gomillion

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Bone Repair ◽

Structural Integrity ◽

Three Dimensional ◽

Cellular Responses ◽

Bone Substitutes ◽

Conductive Materials ◽

Current State

Bone tissue engineering strategies attempt to regenerate bone tissue lost due to injury or disease. Three-dimensional (3D) scaffolds maintain structural integrity and provide support, while improving tissue regeneration through amplified cellular responses between implanted materials and native tissues. Through this, scaffolds that show great osteoinductive abilities as well as desirable mechanical properties have been studied. Recently, scaffolding for engineered bone-like tissues have evolved with the use of conductive materials for increased scaffold bioactivity. These materials make use of several characteristics that have been shown to be useful in tissue engineering applications and combine them in the hope of improved cellular responses through stimulation (i.e., mechanical or electrical). With the addition of conductive materials, these bioactive synthetic bone substitutes could result in improved regeneration outcomes by reducing current factors limiting the effectiveness of existing scaffolding materials. This review seeks to overview the challenges associated with the current state of bone tissue engineering, the need to produce new grafting substitutes, and the promising future that conductive materials present towards alleviating the issues associated with bone repair and regeneration.

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Synthetic and Marine-Derived Porous Scaffolds for Bone Tissue Engineering

Materials ◽

10.3390/ma11091702 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1702 ◽

Cited By ~ 22

Author(s):

Ana Neto ◽

José Ferreira

Keyword(s):

Tissue Engineering ◽

Bone Graft ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Bone Repair ◽

The Body ◽

Porous Scaffolds ◽

Porous Structures ◽

Promising Alternative ◽

Bone Properties

Bone is a vascularized and connective tissue. The cortical bone is the main part responsible for the support and protection of the remaining systems and organs of the body. The trabecular spongy bone serves as the storage of ions and bone marrow. As a dynamic tissue, bone is in a constant remodelling process to adapt to the mechanical demands and to repair small lesions that may occur. Nevertheless, due to the increased incidence of bone disorders, the need for bone grafts has been growing over the past decades and the development of an ideal bone graft with optimal properties remains a clinical challenge. This review addresses the bone properties (morphology, composition, and their repair and regeneration capacity) and puts the focus on the potential strategies for developing bone repair and regeneration materials. It describes the requirements for designing a suitable scaffold material, types of materials (polymers, ceramics, and composites), and techniques to obtain the porous structures (additive manufacturing techniques like robocasting or derived from marine skeletons) for bone tissue engineering applications. Overall, the main objective of this review is to gather the knowledge on the materials and methods used for the production of scaffolds for bone tissue engineering and to highlight the potential of natural porous structures such as marine skeletons as promising alternative bone graft substitute materials without any further mineralogical changes, or after partial or total transformation into calcium phosphate.

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Exploration of gum ghatti-modified porous scaffolds for bone tissue engineering applications

New Journal of Chemistry ◽

10.1039/c9nj05575d ◽

2020 ◽

Vol 44 (6) ◽

pp. 2389-2401 ◽

Cited By ~ 4

Author(s):

J. Anita Lett ◽

Suresh Sagadevan ◽

Zohreh Shahnavaz ◽

Muthiah Bavani Latha ◽

Karthick Alagarswamy ◽

...

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Bone Repair ◽

Porous Scaffolds ◽

Engineering Applications ◽

Gum Ghatti ◽

Hydroxyl Apatite

Taking advantage of the tissue engineering principles, the formed hydroxyl apatite-modified gum ghatti biomaterial with its porous nature, biocompatibility, and efficient mechanical properties can be potential for the bone repair and regeneration.

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Recent Developments of Functional Scaffolds for Craniomaxillofacial Bone Tissue Engineering Applications

The Scientific World JOURNAL ◽

10.1155/2013/863157 ◽

2013 ◽

Vol 2013 ◽

pp. 1-21 ◽

Cited By ~ 42

Author(s):

Yukihiko Kinoshita ◽

Hatsuhiko Maeda

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Donor Site ◽

Three Dimensional ◽

Bone Substitutes ◽

Bone Defects ◽

Donor Site Morbidity ◽

Autogenous Bone ◽

Recent Developments

Autogenous bone grafting remains a gold standard for the reconstruction critical-sized bone defects in the craniomaxillofacial region. Nevertheless, this graft procedure has several disadvantages such as restricted availability, donor-site morbidity, and limitations in regard to fully restoring the complicated three-dimensional structures in the craniomaxillofacial bone. The ultimate goal of craniomaxillofacial bone reconstruction is the regeneration of the physiological bone that simultaneously fulfills both morphological and functional restorations. Developments of tissue engineering in the last two decades have brought such a goal closer to reality. In bone tissue engineering, the scaffolds are fundamental, elemental and mesenchymal stem cells/osteoprogenitor cells and bioactive factors. A variety of scaffolds have been developed and used as spacemakers, biodegradable bone substitutes for transplanting to the new bone, matrices of drug delivery system, or supporting structures enhancing adhesion, proliferation, and matrix production of seeded cells according to the circumstances of the bone defects. However, scaffolds to be clinically completely satisfied have not been developed yet. Development of more functional scaffolds is required to be applied widely to cranio-maxillofacial bone defects. This paper reviews recent trends of scaffolds for crania-maxillofacial bone tissue engineering, including our studies.

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Development of Biopolymeric Hybrid Scaffold-Based on AAc/GO/nHAp/TiO2 Nanocomposite for Bone Tissue Engineering: In-Vitro Analysis

Nanomaterials ◽

10.3390/nano11051319 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1319

Author(s):

Muhammad Umar Aslam Khan ◽

Wafa Shamsan Al-Arjan ◽

Mona Saad Binkadem ◽

Hassan Mehboob ◽

Adnan Haider ◽

...

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Guar Gum ◽

Porous Scaffolds ◽

Vitro Assay ◽

Vitro Analysis ◽

Nanocomposite Scaffolds

Bone tissue engineering is an advanced field for treatment of fractured bones to restore/regulate biological functions. Biopolymeric/bioceramic-based hybrid nanocomposite scaffolds are potential biomaterials for bone tissue because of biodegradable and biocompatible characteristics. We report synthesis of nanocomposite based on acrylic acid (AAc)/guar gum (GG), nano-hydroxyapatite (HAp NPs), titanium nanoparticles (TiO2 NPs), and optimum graphene oxide (GO) amount via free radical polymerization method. Porous scaffolds were fabricated through freeze-drying technique and coated with silver sulphadiazine. Different techniques were used to investigate functional group, crystal structural properties, morphology/elemental properties, porosity, and mechanical properties of fabricated scaffolds. Results show that increasing amount of TiO2 in combination with optimized GO has improved physicochemical and microstructural properties, mechanical properties (compressive strength (2.96 to 13.31 MPa) and Young’s modulus (39.56 to 300.81 MPa)), and porous properties (pore size (256.11 to 107.42 μm) and porosity (79.97 to 44.32%)). After 150 min, silver sulfadiazine release was found to be ~94.1%. In vitro assay of scaffolds also exhibited promising results against mouse pre-osteoblast (MC3T3-E1) cell lines. Hence, these fabricated scaffolds would be potential biomaterials for bone tissue engineering in biomedical engineering.

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