Bioactive composites for bone tissue engineering

One of the major challenges of bone tissue engineering is the production of a suitable scaffold material. In this review the current composite materials options available are considered covering both the methods of both production and assessing the scaffolds. A range of production routes have been investigated ranging from the use of porogens to produce the porosity through to controlled deposition methods. The testing regimes have included mechanical testing of the materials produced through to in vivo testing of the scaffolds. While the ideal scaffold material has not yet been produced, progress is being made

Bone tissue engineering

Medical advances have led to a welcome increase in life expectancy. However, accompanying longevity introduces new challenges: increases in age-related diseases and associated reductions in quality of life. The loss of skeletal tissue that can accompany trauma, injury, disease or advancing years can result in significant morbidity and significant socio-economic cost and emphasise the need for new, more reliable skeletal regeneration strategies. To address the unmet need for bone augmentation, tissue engineering and regenerative medicine have come to the fore in recent years with new approaches for de novo skeletal tissue formation. Typically, these approaches seek to harness stem cells, innovative scaffolds and biological factors that promise enhanced and more reliable bone formation strategies to improve the quality of life for many. This review provides an overview of recent developments in bone tissue engineering focusing on skeletal stem cells, vascular development, bone formation and the translation from preclinical in vivo models to clinical delivery

Embryonic stem cells in bone tissue engineering

Due to increased life expectancy of humans the number of patients with age related skeletal compliciations has increased. These patients but also patients suffering from complications due to trauma or disease often need surgical interventions in which additional bone is required for optimal recovery. Currently the most frequently used bone replacement is autologous or allogeneic bone, but both methods have their drawbacks

Cell-Based Bone Tissue Engineering

The authors review the available data on bone tissue engineering and discuss possible new research areas that could help to make bone tissue engineering a clinical success

Guest editorial: special issue on bone tissue engineering

No abstract availabl

Continuum Modeling and Simulation in Bone Tissue Engineering

Bone tissue engineering is currently a mature methodology from a research perspective. Moreover, modeling and simulation of involved processes and phenomena in BTE have been proved in a number of papers to be an excellent assessment tool in the stages of design and proof of concept through in-vivo or in-vitro experimentation. In this paper, a review of the most relevant contributions in modeling and simulation, in silico, in BTE applications is conducted. The most popular in silico simulations in BTE are classified into: (i) Mechanics modeling and sca old design, (ii) transport and flow modeling, and (iii) modeling of physical phenomena. The paper is restricted to the review of the numerical implementation and simulation of continuum theories applied to di erent processes in BTE, such that molecular dynamics or discrete approaches are out of the scope of the paper. Two main conclusions are drawn at the end of the paper: First, the great potential and advantages that in silico simulation o ers in BTE, and second, the need for interdisciplinary collaboration to further validate numerical models developed in BTE.Ministerio de Economía y Competitividad del Gobierno España DPI2017-82501-

Induction of osteoblast differentiation markers in human dermal fibroblasts: potential application to bone tissue engineering.

Tissue engineered constructs have the potential to be used as replacements for current bone graft technologies. One component necessary for bone tissue engineering is a readily available, osteogenic cell source. Human dermal fibroblasts may have the potential to differentiate along an osteoblastic lineage, making them a candidate for use in bone tissue engineering applications. The objective of this study was to validate the ability of dermal fibroblasts to express gene and protein markers of osteoblastic differentiation and to explore their potential, in combination with biomaterial scaffolds and signaling factors, for use in bone tissue engineering

3D Printed Polycaprolactone/Gelatin/Bacterial Cellulose/Hydroxyapatite Composite Scaffold for Bone Tissue Engineering

Three-dimensional (3D) printing application is a promising method for bone tissue engineering. For enhanced bone tissue regeneration, it is essential to have printable composite materials with appealing properties such as construct porous, mechanical strength, thermal properties, controlled degradation rates, and the presence of bioactive materials. In this study, polycaprolactone (PCL), gelatin (GEL), bacterial cellulose (BC), and different hydroxyapatite (HA) concentrations were used to fabricate a novel PCL/GEL/BC/HA composite scaffold using 3D printing method for bone tissue engineering applications. Pore structure, mechanical, thermal, and chemical analyses were evaluated. 3D scaffolds with an ideal pore size (~300 µm) for use in bone tissue engineering were generated. The addition of both bacterial cellulose (BC) and hydroxyapatite (HA) into PCL/GEL scaffold increased cell proliferation and attachment. PCL/GEL/BC/HA composite scaffolds provide a potential for bone tissue engineering applications

Nanoparticles for bone tissue engineering

Tissue engineering (TE) envisions the creation of functional substitutes for damaged tissues through integrated solutions, where medical, biological, and engineering principles are combined. Bone regeneration is one of the areas in which designing a model that mimics all tissue properties is still a challenge. The hierarchical structure and high vascularization of bone hampers a TE approach, especially in large bone defects. Nanotechnology can open up a new era for TE, allowing the creation of nanostructures that are comparable in size to those appearing in natural bone. Therefore, nanoengineered systems are now able to more closely mimic the structures observed in naturally occurring systems, and it is also possible to combine several approaches - such as drug delivery and cell labeling - within a single system. This review aims to cover the most recent developments on the use of different nanoparticles for bone TE, with emphasis on their application for scaffolds improvement; drug and gene delivery carriers, and labeling techniques.This study was funded by QREN (ON.2 - NORTE-01-0124-FEDER-000018), as well as the European Union’s FP7 Programme under grant agreement number REGPOTCT2012-316331-POLARIS. Sılvia Vieira was awarded an FCT PhD scholarship (SFRH/BD/102710/2014). The FCT distinction attributed to J.M.O. under the Investigator FCT program (IF/00423/2012 and IF/01285/2015) is also greatly acknowledged.info:eu-repo/semantics/publishedVersio

Advances in Bone Tissue Engineering

Bone deficiencies, caused by malformations, trauma or adverse effects from medical treatments, are a clinical challenge and often associated with reduced physical function and quality of life. Autologeous bone grafts can be used to reconstruct skeletal defects, but the right size and quality of bone might not always be available and even so, donor-site morbidity might follow. A pre-fabricated or tissue engineered material has been proposed as an alternative means of addressing these limitations. By combining bone forming cells, growth factors and scaffolding materials, this technique has the potential to generate custom made bone grafts. The main objectives for this thesis were to optimize the conditions for bone tissue engineering, to introduce new perspectives and to gain further understanding of the involved components. In study I, the scaffolding material hydroxyapatite was coated with fibronectine and serum to augment the materials bioactivity and cell carrying capacity. Cell attachment and growth were significantly enhanced by the surface manipulation in vitro. Similar trends were found for in vivo cell delivery, but the difference was not statistically significant compared to the controls. In study II, mesenchymal stem cell (MSC) growth was accelerated in 2-D and 3-D cultures by transient downregulation of cell cycle regulator p21, using short interfering RNA. In study III, MSCs were transduced with adenoviruses to express BMP2 and VEGF. An interesting interaction was discovered, where VEGF was shown to inhibit simultaneous BMP2 expression. In study IV, a periosteum-like graft was engineered, using the dermal matrix AlloDerm and seeded MSCs. When the seeded cells were transduced to express BMP2, the created periosteum proved capable of inducing ectopic bone formation in muscle and healed a critical-sized bone defect in rat mandible. Collectively, the presented studies highlight important aspects and current limitations of bone tissue engineering. A new approach was introduced in facilitating the process of bone formation and regeneration, and valuable insights were gained regarding stem cell manipulation and behavior. Furthermore, a novel strategy to induce bone formation and healing through the use of a manufactured periosteum was presented