Distribution by Scientific Domains
Distribution within Polymers and Materials Science

Kinds of Biomaterials

  • polymeric biomaterials

  • Selected Abstracts

    Skin Repair Using a Porcine Collagen I/III Membrane,Vascularization and Epithelization Properties

    BACKGROUND Collagen membranes have been developed to overcome the problem of limited availability of skin grafts. Vascularization and restricted functional epithelization limit the success of bioartificial constructs. OBJECTIVE To compare the vascularization, epithelization, and integration of a porcine collagen I/III membrane with that of split-thickness skin grafts on skin wounds. MATERIALS AND METHODS In 21 adult pigs, full-thickness skin defects on the rear side of the ear healed by split-thickness skin grafting, by covering with the membrane, or by free granulation. Skin samples on postoperative days 1, 3, 7, 14, 21, and 28 were evaluated histologically (hematoxylin-eosin, Sirius Red) and using immunohistochemistry (cytokeratin 5/6, transforming growth factor beta receptor (TGF,R-III) and immunoblot (TGF,1,3, Smad2/3). Epithelial thickness and TGF,R-III-positive capillary area were quantitatively assessed. RESULTS Epithelization and vascularization in the membrane group were not significantly different from in the group treated with a split-thickness skin graft. Free granulation showed significantly slower epithelization and vascularization (p<.05). TGF,1 and Smad2/3 complex expression were high during free granulation. Matrix was distinguishable until day 7. CONCLUSIONS This membrane serves as a suitable full-thickness dermal substitute, because the membrane is vascularized faster than free granulation tissue and enables early epithelization. Geistlich Biomaterials (Wolhusen, Switzerland) provided the collagen membrane used in this study [source]

    Quantitative Chemical Mapping of Relevant Trace Elements at Biomaterials/Biological Media Interfaces by Ion Beam Methods

    Edouard Jallot
    The definition of biomaterial as proposed by the European Society for Biomaterials in 1986 puts forward the overall importance of the notion of contact between the biomaterial and biological medium (cell, tissue, fluid,,). The underlying concept of biocompatibility makes the interface between biomaterial and biological medium a privileged zone of interest. In this paper, we would like to give an exhaustive view of how ion beams techniques can contribute to a better understanding of such interface taking several examples dealing with bone tissue substitution. After a short presentation of ion beams techniques the paper will focus on PIXE/RBS spectroscopies and will give the basics of these coupled technique. Three examples will then be presented to illustrate the interest of these techniques to study biomaterials/biological interactions. The first example deals with metallic alloys based joint prostheses. The ionic release from the prosthesis and the wear behavior of total knee prostheses will be presented. In the last two examples, bioactive materials will be studied. The common characteristic of bioactive ceramics is the kinetic modification of their surface upon interaction which is ideally monitored by PIXE chemical mapping. The second example will review the benefit of using PIXE/RBS technique to study the effect of doping of bioactive glasses on the very first steps involved in the bioactivity mechanisms like dissolution, ionic release, and biomineralization onto the surface of the glasses. Finally, protein delivery systems based upon mesoporous hydroxyapatites will be studied. Chemical mapping allowing the quantitative determination of protein distribution inside the HAp grains will be presented for the first time. [source]

    Advanced Biomaterials 2010: Growth

    Prof. Klaus D. Jandt Section Editor Advanced Biomaterials
    No abstract is available for this article. [source]

    Computational Methods for the Development of Polymeric Biomaterials

    Aurora D. Costache
    This review focuses on polymeric biomaterials and provides a selective overview of the computational modeling approaches used to predict their properties and biological responses. Also, a short overview of existing databases and software packages for the biomaterials field is presented. The review summarizes the research in this area since the year 2000. [source]

    Inside Front Cover ,Advanced Biomaterials 1/2009

    Andrés F. Lasagni
    The cover picture by Lasagni et. al shows two-dimensional periodic microstructures of polyethylene glycol diacrylate (PEG-DA) fabricated using nanosecond (top) and femtosecond (bellow) multibeam laser interference patterning (MLI). The periodic topography can be varied by simple control of the interference patterns as well as exposure dosages. Such structures with controlled topography are of relevant importance for applications in biomedical devices. [source]

    Inside Front Cover Advanced Biomaterials 2/2008)

    Article first published online: 27 OCT 200
    No abstract is available for this article. [source]

    Progress and Challenge for Magnesium Alloys as Biomaterials,

    R. Zeng
    Abstract Magnesium alloys are very biocompatiable and show promise for use in orthopaedic implant. Significant progress of research on bioabsorbable magnesium stents and orthopaedic bones has been achieved in recent years. The issues on degradation, hydrogen evolution, and corrosion fatigue and erosion corrosion of magnesium alloys and various influencing factors in simulated body fluid (SBF) are discussed. The research progress on magnesium and its alloys as biomaterials and miscellaneous approaches to enhancement in corrosion resistance is reviewed. Finally the challenges and strategy for their application as orthopaedic biomaterials are also proposed. [source]

    Designer Biomaterials for Nanomedicine

    Nishit Doshi
    Abstract Nanotechnology has had tremendous impact on medical science and has resulted in phenomenal progress in the field of drug delivery and diagnostics. A wide spectrum of novel nanomaterials including polymeric particles, liposomes, quantum dots, and iron oxide particles have been developed for applications in therapeutic delivery and diagnostics. This has resulted in control over the rate and period of delivery and targeting of drugs to specific organs in the human body. This feature article focuses on the delivery of drugs using polymeric particles. The size, choice of polymer, surface chemistry, shape, and mechanical properties of the particles are parameters that critically affect particle function. Numerous biomaterials and fabrication techniques have been developed in the last decade that focus on novel design parameters, such as shape and mechanical properties and the interplay of these parameters with the size and surface chemistry of particles. Recent advances with particular focus on the importance of particle shape are highlighted, and the challenges that are yet to be fulfilled are underscored. [source]

    Neural Interface Biomaterials: Multifunctional Nanobiomaterials for Neural Interfaces (Adv. Funct.

    Neural electrodes are designed to interface with the nervous system and provide control signals for neural prostheses. However, robust and reliable chronic recording and stimulation remains a challenge for neural electrodes. On page 573, Mohammad Reza Abidian and David Martin report a novel method for the fabrication of soft, low impedance, high charge density, and controlled releasing nanobiomaterials that can be applied for neural interfaces using drug loaded nanofibers, 3D conducting polymer nanostructures (PEDOT), and alginate hydrogel. [source]

    Nanostructured Biomaterials for Regeneration,

    Guobao Wei
    Abstract Biomaterials play a pivotal role in regenerative medicine, which aims to regenerate and replace lost/dysfunctional tissues or organs. Biomaterials (scaffolds) serve as temporary 3D substrates to guide neo tissue formation and organization. It is often beneficial for a scaffolding material to mimic the characteristics of extracellular matrix (ECM) at the nanometer scale and to induce certain natural developmental or/and wound healing processes for tissue regeneration applications. This article reviews the fabrication and modification technologies for nanofibrous, nanocomposite, and nanostructured drug-delivering scaffolds. ECM-mimicking nanostructured biomaterials have been shown to actively regulate cellular responses including attachment, proliferation, differentiation, and matrix deposition. Nanoscaled drug delivery systems can be successfully incorporated into a porous 3D scaffold to enhance the tissue regeneration capacity. In conclusion, nanostructured biomateials are a very exciting and rapidly expanding research area, and are providing new enabling technologies for regenerative medicine. [source]

    Regenerative Medicine: (Adv. Mater.

    ADVANCED MATERIALS, Issue 32-33 2009
    Biomaterials are essential "elements" in Regenerative Medicine strategies. The role of such smart polymer systems (center left) is to support or control the endogenous regeneration for a specific duration and therefore are designed to degrade (upper left), to control cell function (lower right), substitute the extracellular matrix (background), or to control the sustained release of bioactive molecules (upper right). Images in the front cover courtesy of Andreas Lendlein, Dieter Hofmann, Anna Marie Lipski, Michael Schossig, Jay C. Sy, and V. Prasad Shastri. [source]

    Knowledge-Based Approach towards Hydrolytic Degradation of Polymer-Based Biomaterials

    ADVANCED MATERIALS, Issue 32-33 2009
    Dieter Hofmann
    Abstract The concept of hydrolytically degradable biomaterials was developed to enable the design of temporary implants that substitute or fulfill a certain function as long as required to support (wound) healing processes or to control the release of drugs. Examples are surgical implants, e.g., sutures, or implantable drug depots for treatment of cancer. In both cases degradability can help to avoid a second surgical procedure for explanation. Although degradable surgical sutures are established in the clinical practice for more than 30 years, still more than 40% of surgical sutures applied in clinics today are nondegradable.1 A major limitation of the established degradable suture materials is the fact that their degradation behavior cannot reliably be predicted by applying existing experimental methodologies. Similar concerns also apply to other degradable implants. Therefore, a knowledge-based approach is clearly needed to overcome the described problems and to enable the tailored design of biodegradable polymer materials. In this Progress Report we describe two methods (as examples for tools for this fundamental approach): molecular modeling combining atomistic bulk interface models with quantum chemical studies and experimental investigations of macromolecule degradation in monolayers on Langmuir,Blodgett (LB) troughs. Finally, an outlook on related future research strategies is provided. [source]

    Injectable Biomaterials for Regenerating Complex Craniofacial Tissues,

    ADVANCED MATERIALS, Issue 32-33 2009
    James D. Kretlow
    Abstract Engineering complex tissues requires a precisely formulated combination of cells, spatiotemporally released bioactive factors, and a specialized scaffold support system. Injectable materials, particularly those delivered in aqueous solution, are considered ideal delivery vehicles for cells and bioactive factors and can also be delivered through minimally invasive methods and fill complex 3D shapes. In this review, we examine injectable materials that form scaffolds or networks capable of both replacing tissue function early after delivery and supporting tissue regeneration over a time period of weeks to months. The use of these materials for tissue engineering within the craniofacial complex is challenging but ideal as many highly specialized and functional tissues reside within a small volume in the craniofacial structures and the need for minimally invasive interventions is desirable due to aesthetic considerations. Current biomaterials and strategies used to treat craniofacial defects are examined, followed by a review of craniofacial tissue engineering, and finally an examination of current technologies used for injectable scaffold development and drug and cell delivery using these materials. [source]

    Mapping the Interactions among Biomaterials, Adsorbed Proteins, and Human Embryonic Stem Cells

    ADVANCED MATERIALS, Issue 27 2009
    Ying Mei
    An integrated high-throughput polymer synthesis and rapid material/protein/cell interaction assays were developed to optimize stem cell microenvironments. Microarrayed polymers were synthesized and studied for the ability to support the growth of partially differentiated human embryonic stem cells. In parallel, a programmed laser scanning cytometry system was developed to allow for rapid quantification of cell material interaction. [source]

    Synthesis and Characterization of Hydroxyapatite/Poly(Vinyl Alcohol Phosphate) Nanocomposite Biomaterials

    Nabakumar Pramanik
    A hydroxyapatite (HAp)/poly(vinyl alcohol phosphate) (PVAP) nanocomposite has been prepared by a chemical method by varying the HAp content by 10,60% (w/w). The bonding between HAp and PVAP has been investigated through Fourier transform infrared absorption spectra, X-ray diffraction, and thermogravimetric analyses. Transmission electron microscopy study shows a homogeneous dispersion of nanoparticles in the polymer matrix. Scanning electron microscopy study shows enhancement of the surface roughness of the composite with an increase in the nanoparticle content. The mechanical properties of the composites improve significantly with an increase in the HAp content. The HAp/PVAP nanocomposite prepared may have bone,implant applications. [source]

    Use of Enzymes for the Processing of Biomaterials

    Hidero Unuma
    Ceramic/polymer composites and hollow ceramic microspheres are receiving attention as biomaterials as a bone/tissue substitute and cancer remedy. This article describes the advantages of the use of enzymes as "controllable precipitant supplier" in the processing of such biomaterials. It has been demonstrated that hydroxyapatite (HA)/polymer composites and hollow microspheres of Y2O3, Fe3O4, and HA may be fabricated in a shorter time and using a simpler operation. [source]

    Periodontal repair in dogs: space-providing ePTFE devices increase rhBMP-2/ACS-induced bone formation

    Ulf M.E. Wikesjö
    Abstract Background: Recombinant human bone morphogenetic protein-2 (rhBMP-2) technologies have been shown to enhance alveolar bone formation significantly. Biomaterial (carrier) limitations, however, have restricted their biologic potential for indications where compressive forces may limit the volume of bone formed. The objective of this proof-of-principle study was to evaluate the potential of a space-providing, macroporous ePTFE device to define rhBMP-2-induced alveolar bone formation using a discriminating onlay defect model. Methods: Routine, critical size, 5,6 mm, supra-alveolar, periodontal defects were created around the third and fourth mandibular premolar teeth in four young adult Hound Labrador mongrel dogs. All jaw quadrants received rhBMP-2 (0.4 mg) in an absorbable collagen sponge (ACS) carrier. Contralateral jaw quadrants in subsequent animals were randomly assigned to receive additionally the dome-shaped, macroporous ePTFE device over the rhBMP-2/ACS implant or no additional treatment. The gingival flaps were advanced to cover the ePTFE device and teeth, and sutured. Animals were scheduled for euthanasia to provide for histologic observations of healing at 8 weeks postsurgery. Results: Healing was uneventful without device exposures. New bone formation averaged (±SD) 4.7±0.2 mm (98%) and 4.5±0.4 mm (94%) of the defect height, respectively, for jaw quadrants receiving rhBMP-2/ACS with the ePTFE device or rhBMP-2/ACS alone (p>0.05). In contrast, the regenerated bone area was significantly enhanced in jaw quadrants receiving rhBMP-2/ACS with the ePTFE device compared to rhBMP-2/ACS alone (9.3±2.7 versus 5.1±1.1 mm2; p<0.05). Cementum formation was similar for both treatment groups. Ankylosis compromised periodontal regeneration in all sites. Conclusions: The results suggest that the novel space-providing, macroporous ePTFE device appears suitable as a template to define rhBMP-2/ACS-induced alveolar bone formation. Zusammenfassung Hintergrund: Es wurde gezeigt, dass das rekombinante menschliche knochenmorphogenetische Protein 2 (rhBMP-2) die alveoläre Knochenbildung signifikant erhöht. Limitationen des Biomaterials (Träger) haben jedoch die biologischen Potenzen des Materials für die Indikationen, wo komprimierende Kräfte das Volumen des zu bildenden Knochen limitierten, eingeengt. Das Ziel dieser prinzipiellen geprüften Studie war die Evaluation der Platzhalterfunktion einer makroporösen e-PTFE Membran, um die von rhBMP-2 induzierten Knochenbildung unter Nutzung eines differenzierenden Onlaydefektmodells zu definieren. Methoden: Routinemäßig wurden supraalveoläre parodontale Defekte mit der kritischen Größe von 5,6 mm um die dritten und vierten Prämolaren bei 4 jungen adulten Labrodormischhunden geschaffen. Alle Quadranten erhielten rhBMP-2 (0.4 mg) in einem resorbierbaren Kollagenschwamm (ACS). Kontralaterale Quadranten bei den aufeinander folgenden Tieren wurden zufällig ausgewählt, um zusätzlich eine domförmige makroporöse e-PTFE Membran über das rhBMP-2/ACS Implantat oder keine zusätzliche Therapie zu erhalten. Die gingivalen Lappen wurden so präpariert, dass sie die e-PTFE Membran und Zähne bedeckten und vernäht. Die Tiere wurden 8 Wochen nach der Operation getötet und für histologische Untersuchungen vorbereitet. Ergebnisse: Die Heilung war komplikationslos ohne Exposition der Membran. Die neue Knochenbildung betrug durchschnittlich (±SD) 4.7±0.2 mm (98%) und 4.5±0.4 mm (94%) der Defekthöhe für die Quadranten, die rhBMP-2/ACS mit der e-PTFE Membran erhielten oder rhBMP-2/ACS allein (p>0,05). Im Kontrast dazu war das regenerierte Knochenfeld signifikant erweitert bei den Kieferquadranten, die rhBMP-2/ACS mit e-PTFE Membran erhielten im Vergleich zu denjenigen mit rhBMP-2/ACS allein (9.3±2.7 vs. 5.1±1.1 mm2; p<0.05). Die Zementbildung war in beiden Behandlungsgruppen ähnlich. Ankylosen gefährdeten die parodontalen Regeneration in allen Flächen. Schlussfolgerungen: Die Ergebnisse zeigen, dass die neue makroporöse Platzhalter e-PTFE Membran als Schablone nützlich ist, um die rhBMP-2/ACS induzierte alveoläre Knochenbildung zu betonen. Résumé Contexte: Des technologies utilisant la protéine-2 osseuse morphogénétique humaine recombinée (rhBMP-2) ont montré qu'elle permettait d'augmenter significativement la formation d'os alvéolaire. Les limites du biomatériel (vecteur), cependant, ont restreint leur potentiel biologique aux indications pour lesquels des forces compressives pourraient limiter le volume d'os en formation. L'objectif de cette étude fut d'évaluer le potentiel d'un dispositif en ePTFE macro-poreux permettant de créer un espace pour définir la formation d'os alvéolaire induit par la rhBMP-2 en utilisant un modèle discriminatoire de lésion. Méthodes: Des lésions parodontales supra-alvéolaires de taille critique, 5,6 mm, furent créées autour des troisièmes et quatrièmes prémolaires chez 4 Labrador adultes. Chaque quadrant a été traité par des éponges de collagène résorbables utilisé comme vecteur (ASC) contenant rhBMP-2 (0.4 mg). Les quadrants contralatéraux des animaux furent aléatoirement distribués pour recevoir (ou pas) en plus un dispositif macro-poreux en ePTFE, en forme de dôme sur les implants de rhBMP-2/ACS. Les lambeaux furent déplacés pour recouvrir le dispositif en ePTFE et les dents et suturés. Les animaux furent sacrifiés après 8 semaines pour fournir des observations histologiques de la cicatrisation. Résultats: La cicatrisation ne posait pas de problèmes et on ne nota pas d'exposition des dispositifs. La moyenne de la formation osseuse était de (±SD) 4.7±0.2 mm (98%) et 4.5±0.4 mm (94%) de la hauteur de la lésion, respectivement, pour les quadrants ayant été traités par la rhBMP-2/ACS avec le dispositif en ePTFE ou la rhBMP-2/ACS seule (p>0.05). A l'inverse, la surface osseuse régénérée était significativement plus importante dans les quadrants traités par la rhBMP-2/ACS et les dispositifs en ePTFE par rapport au site traités seulement par la rhBMP-2/ACS (9.3±2.7 vs. 5.1±1.1 mm2; p<0.05). La formation cémentaire était similaire pour les deux groupes de traitement. L'ankylose compromettait la régénération parodontale dans tous les sites. Conclusions: Ces résultats suggèrent que le dispositif en ePTFE macro-poreux, qui assure un espace, semble convenir comme standard pour définir la formation osseuse induite par la rhBMP-2/ACS. [source]

    The effect of a fibrin glue on the integration of Bio-Oss® with bone tissue

    An experimental study in labrador dogs
    Abstract Background: Bio-Oss® is a deproteinized bovine mineral used in bone augmentation procedures. The particles are often mixed with a protein product (Tisseel®) to form a mouldable graft material. Aim: The aim of the present experiment was to study the healing of self-contained bone defects after the placement of Bio-Oss® particles alone or mixed with Tisseel® in cylindrical defects in the edentulous mandibular ridge of dogs. Material and methods: In 4 labrador dogs, the 2nd, 3rd and 4th mandibular premolars were extracted bilaterally. 3 months later, 3 cylindrical bone defects, 4 mm in diameter and 8 mm in depth, were produced in the right side of the mandible. Following a crestal incision, full thickness flaps were raised and the bone defects were prepared with a trephine drill. The defects were filled with Bio-Oss® (Geistlich Biomaterials, Wolhuser, Switzerland) particles alone or mixed with Tisseel® (Immuno AG, Vienna, Austria), or left "untreated". A collagen membrane (Bio-Gide®, Geistlich Biomaterials, Wolhuser, Switzerland) was placed to cover all defects and the flaps were sutured. 2 months later, the defect preparation and grafting procedures were repeated in the left side of the mandible. After another month, the animals were sacrificed and biopsies obtained from the defect sites. Results: Bio-Oss® -treated defects revealed a higher percentage of contact between graft particles and bone tissue than defects treated with Bio-Oss®+ Tisseel® (15% and 30% at 1 and 3 months versus 0.4% and 8%, respectively). Further, the volume of connective tissue in the Bio-Oss® treated defects decreased from the 1 to the 3 month interval (from 44% to 30%). This soft tissue was replaced with newly formed bone. In the Bio-Oss®+ Tisseel® treated defects, however, the proportion of connective tissue remained unchanged between 1 and 3 months. Conclusion: The adjunct of Tisseel® may jeopardize the integration of Bio-Oss® particles with bone tissue. Zusammenfassung Hintergrund: Bio-Oss® ist ein entproteiniertes Mineral vom Schwein, was bei knöchernen Augmentationen verwendet wird. Die Partikel werden oft mit einem Proteinprodukt gemischt, um ein formbares Implantationsmaterial zu erhalten. Ziel: Das Ziel des vorliegenden Experimentes war das Studium der Heilung von selbst-erhaltenden Knochendefekten nach der Anwendung von Bio-Oss® Partikeln allein oder vermischt mit Tisseel® in zylindrischen Defekten im zahnlosen unteren Kieferkamm von Hunden. Materal und Methoden: Bei 4 Labradorhunden wurden die 2., 3. und 4. unteren Prämolaren beidseitig extrahiert. 3 Monate später wurden 3 zylindrische Knochendefekte, 4 mm im Durchmesser und 8 mm tief, auf der rechten Seite des Unterkiefers hergestellt. Nach einer krestalen Incision wurde ein voller Mukoperiostlappen mobilisiert und die knöchernen Defekte mit einem Trepanfräser präpariert. Die Defekte wurden mit Bio-Oss® Partikeln (Geistlich Biomaterial, Wolhuser, Schweiz) allen oder gemischt mit Tisseel® (Immuno AG, Wien, Österreich) gefüllt oder blieben "unbehandelt". Eine Kollagenmembran (Bio-Gide®, Geistlich Biomaterial, Wolhuser, Schweiz) wurde zur Abdeckung über alle Defekte gelegt und die Lappen reponiert und vernäht. 2 Monate später wurden die Defektpräparationen und die Implantationsmaßnahmen auf der linken Seite des Unterkiefers widerholt. Nach einem weiteren Monat wurden die Tiere getötet und Biopsien von den Defektseiten gewonnen. Ergebnisse: Mit Bio-Oss® behandelte Defekte zeigten einen höheren Prozentsatz von Kontakt zwischen Implantationsmaterial und Knochengewebe als die Defekte, die mit Bio-Oss® und Tisseel® behandelt worden waren (15% und 30% zum 1. Monat und 3. Monat versus 0.4% und 8%). Weiterhin verringerte sich das Volumen des Bindegewebes in den mit Bio-Oss® behandelten Defekten vom 1. zum 3. Monat (von 44% zu 30%). Dieses Weichgewebe wurde mit neu gebildetem Knochen ersetzt. In dem mit Bio-Oss® und Tisseel® behandelten Defekten blieb die Verteilung des Bindegewebes zwischen dem 1. und 3. Monat unverändert. Zusammenfassung: Die Zugabe von Tisseel® kann die Integration von Bio-Oss® Partikeln mit Knochengewebe behindern. Résumé Origine: Le Bio-Oss® est un minéral bovin déprotéine utilisé pour les épaississements osseux. Les particules sont souvent mélangées avec un produit protéiné (Tisseel®) pour former un matérial de greffe malléable. But. Le but de l'étude présente a été d'étudier la guérison des lésions osseuses après le placement de particules de Bio-Oss® seules ou mélangées au Tisseel® dans des lésions cylindriques au niveau de la mandibule édentée de labradors. Matériaux et méthodes: Chez 4 labradors les 2ièmes, 3ièmes et 4ièmes prémolaires inférieures ont été avulsées bilatéralement. 3 mois après, 3 lésions osseuses et cylindriques de 4 mm de diamètre et de 8 mm de profondeur ont été produites du côté droit de la mandibule. A la suite d'une incision crestale, des lambeaux d'épaisseur complète ont été relevés et les lésions osseuses préparées avec un trépan. Les lésions ont été comblées par des particules de Bio-Oss® seul (Geistlich Biomaterials, Wolhuser, Suisse) ou mélangées au Tisseel® (Immuno AG, Vienne) ou laissées non-traitées. Une membrane collagène (Bio-Gide®, Geistlich Biomaterials, Wolhuser, Suisse) a été placée pour recouvrir toutes les lésions et les lambeaux ont ensuite été suturés. 2 mois après, les processus précités ont été répétés au niveau gauche de la mandibule. 1 mois plus tard, les animaux ont été tués et les biopsies prélevées. Résultats: Les lésions traitées par le Bio-Oss® ont révélé un % plus important de contact entre les particules du greffon et le tissu osseux que les lésions traitées avec le Bio-Oss®+Tisseel® (respectivement 15% à 30% à 1 et 3 mois versus 0.4% et 8%). De plus le volume de tissu conjonctif dans les lésions traitées par Bio-Oss® diminuait du mois 1 au mois 3, de 44 à 30%. Ce tissu mou a été remplacé par un os néoformé. Dans les lésions traitées par Bio-Oss®+Tisseel®, la proportion de tissu conjonctif demeurait inchangée entre les mois 1 et 3. Conclusions: L'addition de Tisseel® peut mettre en péril l'intégration des particules de Bio-Oss® au tissu osseux. [source]

    Relevance of Osteoinductive Biomaterials in Critical-Sized Orthotopic Defect

    Pamela Habibovic
    Abstract Several publications have shown the phenomenon of osteoinduction by biomaterials to be real. However, whether the ability of a biomaterial to initiate bone formation in ectopic implantation sites improves the performance of such osteoinductive biomaterial in clinically relevant orthotopic sites remains unclear. No studies have been published in which osteoinductive potential of a biomaterial is directly related to its performance orthotopically. In this study, we compared osteoinductive and nonosteoinductive biphasic calcium,phosphate (BCP) ceramics ectopically and in a clinically relevant critical-sized orthotopic defect in goats. The two materials, BCP1150 and BCP1300, had similar chemical compositions, crystallinities, and macrostructures, but their microstructures differed significantly. BCP1150, sintered at a lower temperature, had a large amount of micropores, small average crystal size, and hence a high specific surface area. In contrast, BCP1300, with few micropores, had a significantly lower specific surface area as compared to BCP1150. Twelve-week intramuscular implantation in goats (n,=,10) showed that bone was induced in all BCP1150 implants, while no signs of bone formation were found in any of the BCP1300 implants. After 12 weeks of implantation in a bilateral critical-sized iliac wing defect in the same goats, BCP1150 showed significantly more bone than BCP1300. In addition, the analysis of fluorochrome markers, which were administered to the animals 4, 6, and 8 weeks after implantation to follow the bone growth dynamics, showed an earlier start of bone formation in BCP1150 as compared to BCP1300. Significantly better performance of an osteoinductive ceramic in a critical-sized orthotopic defect in a large animal model in comparison to a nonosteoinductive ceramic suggests osteoinduction to be clinically relevant. Further improvement of material osteoinductive properties is thus a significant step forward in the search for alternatives for autologous bone graft. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source]

    Biomaterials: Status, challenges, and perspectives

    AICHE JOURNAL, Issue 7 2000
    Robert Langer
    First page of article [source]

    Myocardial tissue engineering: a review

    H. Jawad
    Abstract Myocardial tissue engineering, a concept that intends to overcome the obstacles to prolonging patients' life after myocardial infarction, is continuously improving. It comprises a biomaterial based ,vehicle', either a porous scaffold or dense patch, made of either natural or synthetic polymeric materials, to aid transportation of cells into the diseased region in the heart. Many different cell types have been suggested for cell therapy and myocardial tissue engineering. These include both autologous and embryonic stem cells, both having their advantages and disadvantages. Biomaterials suggested for this specific tissue-engineering application need to be biocompatible with the cardiac cells and have particular mechanical properties matching those of native myocardium, so that the delivered donor cells integrate and remain intact in vivo. Although much research is being carried out, many questions still remain unanswered requiring further research efforts. In this review, we discuss the various approaches reported in the field of myocardial tissue engineering, focusing on the achievements of combining biomaterials and cells by various techniques to repair the infarcted region, also providing an insight on clinical trials and possible cell sources in cell therapy. Alternative suggestions to myocardial tissue engineering, in situ engineering and left ventricular devices are also discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Three-Dimensional Polycaprolactone Hierarchical Scaffolds Supplemented with Natural Biomaterials to Enhance Mesenchymal Stem Cell Proliferation

    Hyeon Yoon
    Abstract A hybrid technology that combines a three-dimensional (3-D) dispensing system with an electrospinning process was used to produce a hierarchical 3-D scaffold consisting of micro-sized polycaprolactone (PCL) strands and micro/nano-sized fibres. The micro/nanofibre biocomposites electrospun with PCL/small intestine submucosa (SIS) and PCL/Silk fibroin were layered between melt-plotted micro-strands. The scaffold containing SIS exhibited a stronger hydrophilic property than other scaffolds due to the various hydrophilic components in SIS. The 3-D hierarchical scaffold having biocomposites exhibited an incredibly enhanced initial cell attachment and proliferation of bone marrow-derived mesenchymal stem cells relative to the normally designed 3-D scaffold. [source]

    Biomaterials: Fundamentals and Clinical Applications

    H. P. Jennissen

    Biomaterials-based organic electronic devices

    Christopher J Bettinger
    Abstract Organic electronic devices have demonstrated tremendous versatility in a wide range of applications including consumer electronics, photovoltaics and biotechnology. The traditional interface of organic electronics with biology, biotechnology and medicine occurs in the general field of sensing biological phenomena. For example, the fabrication of hybrid electronic structures using both organic semiconductors and bioactive molecules has led to enhancements in the sensitivity and specificity within biosensing platforms, which in turn has a potentially wide range of clinical applications. However, the interface of biomolecules and organic semiconductors has also recently explored the potential use of natural and synthetic biomaterials as structural components of electronic devices. The fabrication of electronically active systems using biomaterials-based components has the potential to produce a large set of unique devices including environmentally biodegradable systems and bioresorbable temporary medical devices. This article reviews recent advances in the implementation of biomaterials as structural components in organic electronic devices with a focus on potential applications in biotechnology and medicine. Copyright © 2010 Society of Chemical Industry [source]

    A paradigm shift: biomaterials that heal

    Buddy D Ratner
    Abstract Biomaterials based on synthetic polymers have been explored in medicine since early in the 20th century. The inert nature of polymeric materials and their many fabrication options suggested possibilities in medicine to surgeons having to deal with repair and replacement of diseased or injured organs and tissues. Now the biomaterials/medical device industry is estimated at US$ 150 billion worldwide and saves the lives of millions and improves the quality of life for millions more. In spite of the success of biomaterials and medical devices, there are issues with ,biocompatible' biomaterials that have an on impact medical practice and stimulate scientific questions. This perspective discusses the fact that although we have been reasonably successful with implants, there is much room for improvement. Copyright © 2007 Society of Chemical Industry [source]

    Bioactive polyurethanes in clinical applications,

    G. Ciardelli
    Abstract Biomaterials play an important role in most tissue engineering strategies. They can serve as substrates on which cell populations can attach and migrate, can be used as cell delivery vehicles and as bioactive factor carriers to activate specific cellular functions. A series of biodegradable polyurethanes (PUs) with tunable chemical, physical and degradation properties, showing an adequate response to in vitro tests was proposed for applications in soft tissue engineering. Three-dimensional scaffolds of superimposed square meshed grids were prepared by using a rapid prototyping technique (pressure activated microsyringe, PAM) and tested in vivo. Functionalization of PU systems was performed in order to control the chemistry of the materials for the promotion of highly specific binding interactions between materials and biological environments. Two different approaches were used for the coupling of bioactive molecules such as gelatin. The first involved the modification of the polymer chain through a novel monomer and the second one consisted in a surface modification by plasma-induced graft copolymerization of acrylic acid. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    6th Latin American Congress of Artificial Organs and Biomaterials

    ARTIFICIAL ORGANS, Issue 8 2010
    Marivalda De Magalhães Pereira Dr. President of SLABO
    No abstract is available for this article. [source]

    Continuous Delivery of Biomaterials to the Skin,Percutaneous Device Interface Using a Fluid Pump

    ARTIFICIAL ORGANS, Issue 2 2010
    Antonio Peramo
    Abstract We have developed an in vitro culture system composed of organotypic human skin explants interfaced with titanium rods attached to a fluid pump. This device was designed to mimic the process of natural mucosa delivery at the point where a rigid, permanent object penetrates living skin. Full thickness human breast skin explants discarded from surgeries were cultured at different time points at the air-liquid interface. The skin specimens were punctured to fit at the bottom of hollow cylindrical titanium rods. Sodium lauryl sulfate (SLS) was delivered continuously to the specimens through the rods by using an attached fluid pump. Histological analysis of the skin explants as well as no-pump controls was then performed. Our results show substantial differences between controls, where no material was pumped at the interface of rod,skin, and specimens treated with SLS, indicating that the technique of pumping the material is effective in producing observable epithelial changes. These results suggest that an adaptation of this type of device may be useful for the treatment of complications arising from the contact between tissues and percutaneous devices in vivo. [source]

    Hypersensitivity reactions associated with endovascular devices

    CONTACT DERMATITIS, Issue 1 2008
    Golara Honari
    Allergic reactions to endoprostheses are uncommon and reported in association with orthopaedic, dental, endovascular and other implanted devices. Hypersensitivity reactions to the biomaterials used in endovascular prostheses are among the infrequent reactions that may lead to local or systemic complications following cardiovascular therapeutic interventions. This article reviews potential immunotoxic effects of commonly used biomaterials. Reports of putative hypersensitivity reactions to endovascular devices, including coronary stents, perforated foramen occluders, pacemakers and implantable cardioverter defibrillators are also reviewed. [source]

    Bone replacement following dental trauma prior to implant surgery , present status

    Mats Hallman
    Although autogenous bone grafts is considered the ,gold standard', this may be associated with patient morbidity and graft resorption. Consequently, the use of bone substitutes has increased. Today, a substantial number of biomaterials are available on the market, but only a few are well documented. The user should be aware that these biomaterials have different properties: resorbable or non-resorbable, time of resorption and resorption mechanism. The purpose of this review is to describe the function of various bone substitutes and indications for their use in reconstructive implant surgery and to give an overview of the current situation. [source]