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PL
W pracy zaproponowano sposób modelowania poziomych układów stężających z uwzględnieniem rzeczywistych własności układu stężającego w zakresie sztywności i wytrzymałości, który może być użyty przy tworzeniu modeli 3D. Model ten pozwoli zastąpić rekomendowane w normie europejskiej [1] i wytycznych DIBt [2] zastępcze modele statyczne 2D. W modelowaniu zakłada się zastąpienie rzeczywistego poziomego układu stężającego składającego się z płyt pomostowych, układem ramowym o węzłach podatnych.
EN
The aim of this paper was to describe the method of modeling horizontal planes of scaffold used for model 3D. This method can be used instead of the method described in European norm [1] and used in model 2D. The real system of boards was replaced by frame system with semi-rigid joints.
PL
W artykule przedstawiono wyniki badań eksperymentalnych i numerycznych tytanowych rusztowań do hodowli komórkowych. W badaniach strukturalnych z wykorzystaniem mikroskopii skaningowej analizowano wpływ technologii przyrostowej i parametrów procesu technologicznego na kształt i wielkość projektowanych porów. Zaprojektowane konstrukcje o różnej wielkości i kształcie porów zweryfikowano pod kątem wytrzymałości przez symulacje numeryczne metodą elementów skończonych (MES).
EN
The article presents the results of experimental and numerical studies of titanium scaffolds for cell cultures. In structural studies using scanning microscopy, the influence of incremental technology and technological process parameters on the shape and the size of the designed pores was analyzed. The designed constructions of various sizes and pore shapes were verified for strength using numerical simulations by the finite element method (FEM).
PL
W zależności od rodzaju utraconej struktury tkankowej w obrębie układu stomatognatycznego lub przerwania jej ciągłości mogą być wykorzystywane różne biomateriały, które powinny spełniać określone właściwości mechaniczne. Stosowane implanty, skafoldy, a także śruby, mikropłytki lub klamry zazwyczaj wykonane są z tytanu lub jego stopów. Postęp w dziedzinie biomateriałów spowodował, iż współcześnie wykorzystywane są również materiały biodegradowalne, które po spełnieniu swojej funkcji reparacyjnej ulegają samoistnej degradacji (tj. nici chirurgiczne). W pracy przeanalizowano piśmiennictwo dotyczące wykorzystania materiałów biodegradowalnych w stomatologii.
EN
Depending on the type of the lost tissue within the stomatognathic system or breaking of its continuity, various biomaterials having proper mechanical properties can be used. Applied implants, scafolds as well as screws, micro-plates or clamps are usually made of titanium or its alloys. Advances in the field of biomaterials caused that nowadays biodegradable materials are used, and after their reparative function become self-degrading (ie. surgical stitches). The paper analyzes the literature regarding the use of biodegradable materials in dentistry.
EN
This paper discusses the possibilities of obtaining polylactide-based composites and nanocomposites modified with carbon materials using the extrusion method, as well as the potential of their application in 3D printing technology. The aim of this research is to determine the impact of the presence of carbon additives on the properties of composites: mechanical, thermal and chemical. For this purpose, several research techniques were used such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), DSC/TG analysis, infrared Fourier-transform infrared spectroscopy (FTIR) and mechanical tests. It has been shown that it is possible to effectively produce composite materials based on PLA and carbon modifiers after optimization of the extrusion and printing process. Special attention should be paid to the quality of carbon phases homogenization in PLA matrix because the inappropriate dispersion may have a negative effect on the final properties of the composite, especially those modified with nanomaterials. Moreover, the reinforcing effect of carbon phases can be observed, and the quality of obtained filament with carbon fiber after recycling does not differ significantly from the quality of commercially available filaments. The obtained filament was successfully used to print three-dimensional scaffolds. Therefore, both the use of materials which are biodegradable and biocompatible with human tissue and the 3D printing method have the potential to be applied in tissue engineering.
5
Content available Przyczyny techniczne awarii rusztowań. Cz.4
EN
The paper deals with technical aspects which influence the load-bearing capacity and the operation of scaffolds during a construction. The complexity of the problem is presented in the example of failure of a modular scaffold which, after assembly, did not satisfy the conditions for the ultimate limit state and finally it failed due to the wind action. Next the author presented the following technical problems: formation of the main structure of scaffolds, bracing sets, foundation of scaffolds, load-bearing capacity of the anchors, the accuracy of assembly, technical state of the elements, loads acting on scaffolds. The impact of these factors on the possibility of scaffolds failure is illustrated with an example of a facade scaffold. For this scaffold the effort and the natural frequencies were determined in the following situations: the structure with perfect geometry, the structure with imperfections, the scaffold with perfect geometry and taking into account the uneven ground subsidence, and the scaffold with imperfections and uneven subsidence included. The numerical analysis showed that the scaffold does not comply with conditions for the ultimate limit state and that the most important for the capacity of the structure and its proper functioning is the accuracy of the scaffold assembly.
EN
Purpose: The article concerns the development of completely new groups of composite materials that can be used to produce functional replacements for damaged bones or teeth. Design/methodology/approach: A selective laser sintering was used to produce the reinforcement of those materials from titanium and its Ti6Al4V alloy in the form of skeletons with pores with adjustable geometric features. The matrix of those materials is either air or crystallised from the liquid AlSi12 or AlSi7Mg0.3 alloys condition after prior vacuum infiltration or human osteoblast cells from the hFOB 1.19 (Human ATCC - CRL - 11372) culture line. Findings: The porous material may be used for the non-biodegradable scaffold. After implantation into the body in the form of an implant-scaffold one, it allows the natural cells of the patient to grow into the pores of the implant, and it fuses with the bone or the appropriate tissue over time. The essential part of the implant-scaffold is the porous part inseparably connected with the core of solid materials. Into pores can grow living cells. Research limitations/implications: Biological-engineering composite materials in which natural cells were cultured in the pores in the laboratory next are combined as an artificial material with the natural cells of the patient in his/her body. Practical implications: The hybrid technologies of the all group of those materials were obtained and optimised. Numerous structure research was carried out using the most modern research methods of contemporary materials engineering, and mechanical tests and biological research involving the cultivation of natural cells were realised. Originality/value: The results of the research indicate the accuracy of the idea of implementing a new group of biological-engineering materials and the wide possibilities of their application in regenerative medicine.
EN
The results of experimental investigations into foaming process of poly(ε-caprolactone) using supercritical CO2 are presented. The objective of the study was to explore the aspects of fabrication of biodegradable and biocompatible scaffolds that can be applied as a temporary three-dimensional extracellular matrix analog for cells to grow into a new tissue. The influence of foaming process parameters, which have been proven previously to affect significantly scaffold bioactivity, such as pressure (8-18 MPa), temperature (323-373 K) and time of saturation (1-6 h) on microstructure and mechanical properties of produced polymer porous structures is presented. The morphology and mechanical properties of considered materials were analyzed using a scanning electron microscope (SEM), x-ray microtomography (μ-CT) and a static compression test. A precise control over porosity and morphology of obtained polymer porous structures by adjusting the foaming process parameters has been proved. The obtained poly(ε-caprolactone) solid foams prepared using scCO2 have demonstrated sufficient mechanical strength to be applied as scaffolds in tissue engineering.
EN
One of the actual challenges in tissue engineering applications is to efficiently produce as high of number of cells as it is only possible, in the shortest time. In static cultures, the production of animal cell biomass in integrated forms (i.e. aggregates, inoculated scaffolds) is limited due to inefficient diffusion of culture medium components observed in such non-mixed culture systems, especially in the case of cell-inoculated fiber-based dense 3D scaffolds, inside which the intensification of mass transfer is particularly important. The applicability of a prototyped, small-scale, continuously wave-induced agitated system for intensification of anchorage-dependent CP5 chondrocytes proliferation outside and inside three-dimensional poly(lactic acid) (PLA) scaffolds has been discussed. Fibrous PLA-based constructs have been inoculated with CP5 cells and then maintained in two independent incubation systems: (i) non-agitated conditions and (ii) culture with wave-induced agitation. Significantly higher values of the volumetric glucose consumption rate have been noted for the system with the wave-induced agitation. The advantage of the presented wave-induced agitation culture system has been confirmed by lower activity of lactate dehydrogenase (LDH) released from the cells in the samples of culture medium harvested from the agitated cultures, in contrast to rather high values of LDH activity measured for static conditions. Results of the proceeded experiments and their analysis clearly exhibited the feasibility of the culture system supported with continuously wave-induced agitation for robust proliferation of the CP5 chondrocytes on PLA-based structures. Aside from the practicability of the prototyped system, we believe that it could also be applied as a standard method offering advantages for all types of the daily routine laboratory-scale animal cell cultures utilizing various fiber-based biomaterials, with the use of only regular laboratory devices.
9
Content available Łąkotki stawu kolanowego - metody regeneracji
PL
Łąkotki stawu kolanowego są kluczowymi strukturami zapewniającymi prawidłową pracę stawu, a ich usunięcie powoduje zapoczątkowanie nieodwracalnych zmian chorobowych na powierzchniach stawowych. Opracowano wiele metod leczenia uszkodzonych łąkotek, jednak każda z nich charakteryzuje się pewnymi ograniczeniami co do zastosowania. Przezwyciężenie tych ograniczeń poprzez stworzenie implantu, który by doskonale zastępował anatomiczną łąkotkę, jest już podejmowanym, ale jeszcze niezrealizowanym wyzwaniem.
EN
The knee joint menisci are key structures of the joint. They are responsible for the correct joint performance. Their removal results in irreparable chondral damage. There are a few methods of menisci regeneration, but all of them have some limitation in application regard. Overcoming those limitation and creation an implant, which could substitute the anatomical meniscus, is still ongoing, but not yet finalised process.
10
Content available Scaffolds in knee joint meniscus engineering
EN
Introduction and aims: In the knee joint are located two menisci, which play an essential role in the preservation of chondral surfaces and assurance of knee stability. Due to their activity during knee movement, they are strongly exposed to injury not only during professional sport training, but during normal, active life as well. In case of complex degeneration of the meniscal tissue, the regeneration help is needed. This help is provided by polyurethane or collagen meniscus scaffolds. Material and methods: The model of the right knee joint has been designed to in order to investigate the distribution of reduced stresses. The NASTRAN application has been used for calculations. Results: The distribution of the reduced stresses in the right knee joint model are presented in the article. Conclusion: Scaffold is a matrix that is designed to replace the damaged meniscal tissue. It is useful in case of complex tears, for which assessment of biomechanical function restoration after sewing is negative.
PL
Wstęp i cele: W stawie kolanowym znajdują się dwie łąkotki, które odgrywają istotną rolę w zachowaniu powierzchni chrzęstnych oraz zapewniają stabilność kolana. Ze względu na ich aktywność podczas ruchu stawu kolanowego, są silnie narażone na uszkodzenia, nie tylko w profesjonalnym treningu sportowym, ale również w normalnym, aktywnym życiu. W przypadku złożonych uszkodzeń tkanki łąkotki pożądana jest jej regeneracja, która jest wspomagana przez poliuretanowe lub kolagenowe skafoldy łąkotki. Materiał i metody: W celu wykonania badań skonstruowano model prawego stawu kolanowego. Aby otrzymać wartości naprężeń zredukowanych w teście zastosowano program numeryczny NASTRAN. Wyniki: W pracy przedstawiono rozkłady naprężeń zredukowanych w modelu prawego stawu kolanowego. Wniosek: Skafold jest matrycą, która ma zastąpić uszkodzoną tkankę współpracujących powierzchni kolana. Ta metoda regeneracji jest szczególnie użyteczna w przypadkach ujemnej oceny możliwości przywrócenia biomechanicznych funkcji łąkotki po zszyciu.
11
Content available remote Regeneration of knee joint menisci - methods review
EN
At present, there is no need to convince anyone that menisci are crucial structures dealing with a huge number of responsibilities, and its absence in a knee joint results in irretrievable chondral damage. A lot of methods have been recently developed to treat meniscal tears: physical therapy as a first and, for some cases, a last step, bonding by biodegradable sutures, screws, or arrows, collagen and polyurethane scaffolds designed for partial meniscus replacement, and finally allograft transplantation. However, all of them have numerous limitations and can be used in specific conditions only. That is the reason why partial and total meniscectomy is up to this time a common operation in the case of degenerative or complex meniscus tears despite its well-known degenerative consequences. Trials to overcome those limitations are ongoing, and the challenge to invent a long-term successful regeneration method or to design a substitute that well mimics an anatomical meniscus is still in front of us.
EN
An optimal method for composites preparation as an input to rapid prototyping fabrication of scaffolds with potential application in osteochondral tissue engineering is still needed. Scaffolds in tissue engineering applications play a role of constructs providing appropriate mechanical support with defined porosity to assist regeneration of tissue. The aim of the presented study was to analyze the influence of composite fabrication methods on scaffolds mechanical properties. The evaluation was performed on polycaprolactone (PCL) with 5 wt% beta-tricalcium phosphate (TCP) scaffolds fabricated using fused deposition modeling (FDM). Three different methods of PCL-TCP composite preparation: solution casting, particles milling, extrusion and injection were used to provide material for scaffold fabrication. The obtained scaffolds were investigated by means of scanning electron microscope, x-ray micro computed tomography, thermal gravimetric analysis and static material testing machine. All of the scaffolds had the same geometry (cylinder, 4×6 mm) and fiber orientation (0/60/120°). There were some differences in the TCP distribution and formation of the ceramic agglomerates in the scaffolds. They depended on fabrication method. The use of composites prepared by solution casting method resulted in scaffolds with the best combination of compressive strength (5.7±0.2 MPa) and porosity (48.5±2.7 %), both within the range of trabecular bone.
13
EN
Purpose: The aim of the paper is to characterise titanium alloy Ti6Al4V coated by polymeric surface layer as a material for biomedical applications. The paper presents a Selective Laser Melting (SLM) method of fabrication of elements to be used as implants from Ti6Al4V powder. It was demonstrated that the metallic scaffolds created have strictly defined geometric dimensions of an object and open pores, and the pores are regular and repeat within the whole volume of the biomimetic element. Design/methodology/approach: The actual manufacturing process is preceded with creating a model of an element in the stl format that allows to present the element surface by means of a net of triangles. Once the shape is defined of a unit cell and its net parameters, i.e. height, depth and width, they are duplicated with appropriate mathematical algorithms as a result of which a strictly defined, densed and complicated structure of pores defined by a designer is created. Findings: Scanning electron microscopy was applied for showing the structure of pure scaffolds as well as composites made of Ti6Al4V scaffolds coated by polymeric surface layer. Microscope observations were performed using a SEM Zeiss Supra 35 equipped with EDS detectors for chemical composition analysis. Practical implications: Manufactured metal-polymer composites can be used in regenerative medicine as biomimetic implants. Originality/value: The characteristics of biomimetic composites, used in medicine as implants of a palate piece loss with strictly designed geometric shape and dimensions of the object and its strictly planed pores.
EN
Polylactide (PLLA) containing β-TCP is biodegradable composite and an attractive biomaterial for bone tissue engineering, however, hydrophobicity of PLLA based composites is major limitation for their use as scaffolds for cell culture. In our study lecithin was used to improve hydrophilicity and cytocompatibility of PLLA/ β-TCP composite. Thin films of PLLA, PLLA/ β-TCP and PLLA/β-TCP/lecithin were manufactured by solvent-casting technique. Comparative analysis of all types of films was performed. Addition of β-TCP did not change hydrophilicity of PLLA. The hydrophilicity of PLLA/β-TCP/lecithin increased in comparison to PLLA and PLLA/β-TCP. Degradation of PLLA/β-TCP composite surpassed the degradation of PLLA while addition of lecithin diminished the degradation of composite. The cytocompatibility of composites were studied in 7 day long in vitro assay. Human bone derived cells were seeded on all tested surfaces. Cell viability was estimated by Live/Dead fluorescent staining and Alamar Blue test. Surprisingly, although lecithin addition improved hydrophilicity of the PLLA-based composite, adhesion and proliferation of human bone derived cells were markedly hampered on PLLA/β-TCP/lecithin in comparison to PLLA and PLLA/β-TCP. Despite positive effect we found of lecithin addition on hydrophilicity and stability of PLLA-based composite, its effect on cell attachment and proliferation is negative. Hence, incorporation of lecithin did not improve properties of PLLA/β-TCP/lecithin composite intended for bone tissue regeneration.
15
Content available remote Scaffolds for tissue engineering
EN
The paper presents the current trends in medicine of regenerative tissue defect caused by resection of tumors or fractures. Although it is a relatively young field of science, it creates new possibilities for the reconstruction of pathologically altered tissue with the use of three-dimensional scaffolds. Tissue engineering places particular emphasis on the type of scaffold from which they are made because of a number of requirements of medical materials including biocompatibility, mechanical strength and porosity.
PL
Artykuł przedstawia trendy panujące w medycynie w regeneracji ubytków tkankowych powstałych na skutek resekcji nowotworów bądź złamań, skupione na wykorzystaniu inżynierii tkankowej. Ta stosunkowo młoda dziedzina nauki stwarza nowe możliwości odbudowy patologicznie zmienionych tkanek z wykorzystaniem trójwymiarowych rusztowań – skafoldów. Inżynieria tkankowa kładzie szczególny nacisk na rodzaj materiału, z jakiego produkowane są skafoldy, gdyż musi on spełniać szereg wymagań, m.in. biozgodność, wytrzymałość mechaniczna i porowatość.
16
EN
Tissue engineering is a new field of knowledge which creates the possibilities for producing bioactive cardiac prostheses that will characterize by biomechanical and morphological properties similar to native tissue. It is expected that it will be characterized by high durability, which is very important from the social and clinical point of view. The aim of the study was to compare the cytotoxic effect of enzymatic and detergent acellularization methods commonly used for the biological scaffold preparation. It seems that the use of enzymatic methods, allows efficient donor cells removal while maintaining the ability to autologous cell seeding. Heart valves bioprosthesis created using these techniques, may be a good alternative to the currently used prostheses.
PL
Inżynieria tkankowa jest nową dziedziną wiedzy, która stwarza możliwości wytwarzania protez serca bioaktywnych charakteryzujących się właściwościami biomechanicznymi i morfologicznymi zbliżonymi do tkanki rodzimej. Oczekuje się, że proteza serca będzie charakteryzować się wysoką trwałością, co jest bardzo ważne z punktu widzenia społecznego i klinicznego. Celem badania było porównanie efektu cytotoksycznego enzymatycznych i detergentowych metod usuwania komórek, powszechnie stosowanych do wytwarzania biologicznych rusztowań. Wydaje się, że stosowanie metod enzymatycznych, umożliwia wydajne usunięcie komórek dawcy przy zachowaniu zdolności do autologicznego posiewu komórek. Bioprotezy zastawek serca tworzone za pomocą tej techniki mogą być dobrą alternatywą dla obecnie stosowanych mechanicznych i biologicznych protez zastawek serca.
17
Content available remote Ti6Al4V titanium alloy used as a modern biomimetic material
EN
Purpose: The principal aim of the article is to characterise titanium alloy Ti6Al4V as a biomimetic material. The work presents in particular the application of this alloy in regenerative/aesthetic medicine for implants of craniofacial elements against other its other applications in various branches of industry. The article presents a rapid manufacturing (RM) method of fabrication of elements to be used as implants from Ti6Al4V powder. It was demonstrated that the scaffolds created in Selective Laser Melting (SLM) have strictly defined geometric dimensions of an object and open pores, and the pores are regular and repeat within the whole volume of the object. Design/methodology/approach: Scanning electron microscopy was applied for showing the structure of innovative biomimetic materials made of Ti6Al4V powder. Findings: It was confirmed in SEM examinations that the structure of laser-sintered objects consists, within its entire volume, of regularly occurring pores with strictly specified geometric dimensions. Practical implications: Biomimetic materials can be used in regenerative/aesthetic medicine as implants. The purpose of the scaffolds produced is to enable the growth of soft tissue or bone tissue in craniofacial elements. Originality/value: Biomimetic materials can be used in regenerative/aesthetic medicine as implants. The purpose of the scaffolds produced is to enable the growth of soft tissue or bone tissue in craniofacial elements.
EN
Purpose: The purpose of the paper is to present the main results of own research in 3 principal aspects indicating that the research is up to date and modern. This relates to nanotechnologies, modern biomedical materials and rapid manufacturing techniques used for the production of, in particular, microporous materials applied for medical and dental purposes. The paper comprises the explanation of structural mechanisms and phase transformations taking place in newly created engineering nanostructural and microporous materials under the influence of the applied, advanced technological processes newly developed, and especially nanotechnological processes, using the most modern scientific and research equipment being at disposal of modern materials engineering, in particular with the common use of high-resolution transmission electron microscopy (HRTEM). The results of investigations into the formation of the structure and surface properties results according to a different thickness scale of coatings or surface zone, from several hundred nanometres to several millimetres, are presented in the paper, including PVD and CVD coatings and laser treated surface on the steels and light alloys substrates. The paper also describes the nanostructural effects in solid materials, and especially the counteraction of cracking of new-developed high-manganese austenite steels Fe-Mn-Si-Al by twinning or/and martensitic transformation induced by the cold plastic deformation. The article also outlines the results of research of the development of special micro and nanocomposite materials designed mainly for use in regenerative medicine and regenerative dentistry. The studies of the structure and the properties of newly obtained materials and originally developed technologies are included to present the author’s contribution into materials science, nanotechnology, surface engineering and biomedical engineering including the usefulness of the newly developed nanoengineering materials and their applicability, in particular, in regenerative medicine, as well as tissue engineering. The described outcomes of the research constitute a basis for creating, apart from rigid porous implant-scaffolds, an innovative generation of rigid and elastic biological-engineering composite materials for regenerative medicine. Design/methodology/approach: The article discusses the key aspects of own research performed over the last decade in scope of nanotechnologies, modern biomedical materials and rapid manufacturing techniques used for the fabrication of, in particular, microporous materials applied for medical and dental purposes. The conditions for the performance of the research according to the scope mentioned were ensured by implementation of investment projects for constructing and equipping research and didactic laboratories in scope of nanotechnology, technologies of material processes and computational materials science, including LANAMATE (2010-2014) and MERMFLEG (2010-2013), and also BIOFARMA (2010-2012). Practical implications: The obtained materials and technologies are of high practical importance, which was confirmed in many cases with the results of laboratory tests and investigations at a semi-technical scale, and in some cases with the initiation of implementation works. The results of research in scope of bioengineering and dental engineering may find their applications in tissue engineering, in bone surgery, for threedimensional tissue scaffolds and in dentistry or oncology, to replace the natural tissue removed because of a cancer with the possibility of applying a therapeutic agent. Originality/value: The present paper is the original report from a personal own research and explains the concept, scope and results of own research of a new obtained microporous and nanostructural materials and coatings, including hybride solid-porous products and newly obtained materials processing and additive technologies. Some of the mentioned research results are protected by patents or patent applications, and many of them were awarded over 60 prizes and medals at international fairs of innovation, invention and rationalisation in many countries.
19
Content available remote Możliwości wykonania projektów technicznych nietypowych deskowań
PL
W artykule przedstawiono problematykę dotyczącą opracowywania i modelowania nietypowych konstrukcji deskowań. W przypadku nietypowych kształtów i dużej wysokości obiektów oprócz standardowych rozwiązań systemowych deskowań konieczne jest wykorzystanie dodatkowej konstrukcji wsporczej z elementów systemowych, a w bardziej skomplikowanych sytuacjach np. w postaci rusztowań. Ze względu na skomplikowaną budowę poszczególnych elementów systemów deskowań ich projektowanie wymaga indywidualnego podejścia i pewnych uproszczeń modelu numerycznego.
EN
The paper deals with problems of modeling non-typical formwork. In the case of unusual shapes and considerable height in addition to systemic solution is necessary to use an additional supporting structures made of scaffolds. Due to the complicated shape of formwork elements, design require an individual approach and some simplification.
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