Hydroxyapatites of certain alkaline earth metals were synthesised, and their phase composition was determined using X-ray phase analysis. Thermal modification of the studied compounds was performed at temperatures not exceeding 800°C. The laser diffraction method determined the size distribution of the samples subjected to thermal treatment. It was found that the mean particle size ranged from 5,48±1,28 to 126,71±3,68 μm. It has been demonstrated that particle aggregation and fragmentation processes are possible depending on the synthesised compounds' qualitative and quantitative phase composition and the modification temperature.
Composites based on PLA with the addition of 3, 6 and 10 wt% silica, hydroxyapatite and bentonite were obtained by twin-screw extrusion. Maleic anhydride grafted polyethylene was used to enhance interface interactions. The influence of the fillers used on the Charpy impact strength, Rockwell hardness, tensile properties and processing shrinkage was investigated. Test samples were obtained by 3D printing. The highest impact strength and hardness were obtained for the composite containing 10 wt% hydroxyapatite. PLA with 10 wt% hydroxyapatite and 3 wt% bentonite was used to obtain anatomical structures by 3D printing.
PL
Metodą dwuślimakowego wytłaczania otrzymano kompozyty na osnowie PLA z dodatkiem 3, 6 i 10% mas. krzemionki, hydroksyapatytu oraz bentonitu. W celu zwiększenia oddziaływań na granicy faz użyto polietylenu szczepionego bezwodnikiem maleinowym. Zbadano wpływ stosowanych napełniaczy na udarność Charpy’ego, twardość Rockwella, właściwości mechaniczne przy statycznym rozciąganiu oraz skurcz przetwórczy. Próbki do badań otrzymano za pomocą druku 3D. Największą udarność i twardość uzyskano w przypadku kompozytu zawierającego 10% mas. hydroksyapatytu. Do otrzymywania struktur anatomicznych metodą druku 3D zastosowano hybrydowy kompozyt PLA zawierający 10% mas. hydroksyapatytu i 3% mas. bentonitu.
The article is a review of the literature on the use of polymers in medicine as biomaterials. Examples of the preparation of the most commonly used synthetic polymers in medicine, such as: polylactide (PLA), polyglycolide (PGA), polyhydrobutyrate (PHB), polycaprolactone (PCL) are described. The characteristics of ceramic materials: hydroxyapatite (HAp) and tricalcium phosphate (TCP) are also presented in terms of the use of synthetic biodegradable polymers as biofillers. The last part of article is devoted to the functional properties of composites based on PLA with the addition of HAp and TCP.
PL
Artykuł stanowi przegląd literatury dotyczący zastosowania polimerów w medycynie jako biomateriałów. Opisano przykłady otrzymywania najczęściej stosowanych syntetycznych polimerów w medycynie takich jak: polilaktyd (PLA), poliglikolid (PGA), polihydromaślan (PHB), polikaprolakton (PCL). Przedstawiono także charakterystykę materiałów ceramicznych: hydroksyapatytu (HAp) i trójfosforanu wapnia (TCP) pod kontem stosowania jako bionapełniacze syntetycznych biodegradowalnych polimerów. Ostatnia część artykułu jest poświęcona właściwościom użytkowym kompozytów na osnowie PLA z dodatkiem HAp i TCP.
Wankomycyna (VA) jest szeroko stosowanym glikopeptydowym antybiotykiem, o bardzo skutecznym działaniu bakteriobójczym/bakteriostatycznym. Jest stosowana profilaktycznie przed operacjami, po zabiegach lub w ich trakcie wraz z wszczepianym implantem celem zahamowania namnażania się bakterii i zapobiegania infekcji. Pomimo skutecznego działania bakteriobójczego, nieostrożne i niewłaściwe podanie antybiotyku może skutkować toksycznym działaniem prowadzącym do stałych uszkodzeń w ciele. W przeglądzie przedstawiono przykłady połączenia VA z implantami, które pozwalają na precyzyjne dostarczenie leku oraz kontrolę nad czasem jego uwalniania, wspomagając tym samym regenerację tkanki kostnej
EN
Vancomycin (VA) is a widely used glycopeptide antibiotic with highly effective bactericidal/bacteriostatic activity. It is used prophylactically before, after, or during surgery along with an implant to inhibit bacterial proliferation and prevent infection. Despite its effective antibacterial effect, careless and inappropriate administration of the antibiotic can result in toxicity leading to permanent damage in the body. The review provides examples of combining VA with implants that allow precise delivery of the drug and control over the timing of its release, thereby aiding bone tissue regeneration
Purpose: A novel technique of very low-temperature sintering named the cold sintering process is used to produce Highly dense hydroxyapatite-polyetheretherketone (HA-PEEK) nanocomposites. The polymers and ceramics are sintered at different temperatures; therefore, it is difficult to create ceramic matrix composites using traditional methods because the high temperatures might damage the polymers. It is hard to concurrently treat polymeric materials at high temperatures because HA often sinters at temperatures exceeding 1000°C. So, the study aimed to use a novel low-temperature sintering named Cold Sintering Process (CSP) with a Ts/ Tm ratio greater than 0.2 to alleviate this issue. This method could offer a production path with quick densification and less energy costs to increase throughput. Design/methodology/approach: In the current work, two different routes are used: The direct mixing and dissolution methods were used for powder preparation to fabricate a unique ceramic matrix composite. The study aimed to determine whether the preparation method could produce two continuous phases for better densification. The sintering temperature, pressure, holding time, and PEEK content were selected as the production parameters. The samples are characterised using a scanning electron microscope (SEM), X-ray energy dispersive spectrometry (EDS), an X-ray diffractogram (XRD), and a transition electron microscope (TEM). Also, physical and mechanical property measurements were detected, including density, water contact angle, hardness, and diametral tensile strength (DTS). Findings: It can be observed that a high densification compact (relative density 99.3%) can be observed by using the dissolution method HA-PEEK composites, which can be produced via the cold sintering process. The dissolution method can produce two continuous phases compared with the direct mixing method. All samples exhibit excellent hydrophilicity, which makes them good candidates for biomedical applications. Research limitations/implications: The biggest implication of the cold sintering method is the difficulty of making large-sized and complex-shaped samples. Practical implications: The dissolution method can produce two continuous phases compared with the direct mixing method. All samples exhibit excellent hydrophilicity, which makes them good candidates for biomedical applications. Originality/value: A novel technique was used for the first time to solve the problem of producing ceramic matrix composites with polymer as the dispersion phase.
Kompozyty na bazie polikaprolaktonu z dodatkiem wypełniacza w postaci włókien hydroksyapatytowych są jednym z potencjalnych materiałów do zastosowań inżynierii tkankowej. Materiały te odznaczają się nie tylko odpowiednią porowatością i wytrzymałością mechaniczną, lecz także bioaktywnością, biokompatybilnością i bioresorbowalnością. Z punktu widzenia możliwości aplikacyjnych danego materiału niezwykle istotna jest kontrola procesu degradacji kompozytu w czasie, tak aby rusztowanie mogło zapewnić stabilność mechaniczną do momentu odbudowy ubytku. W pracy przedstawiono wyniki badań dotyczące wpływu procesu degradacji na właściwości fizykomechaniczne opracowanych porowatych kompozytów na bazie polikaprolaktonu (PCL) z dodatkiem zsyntezowanych włókien hydroksyapatytu (HA) o zróżnicowanej morfologii. Szczególną uwagę zwrócono na wpływ zsyntezowanego proszku na zmianę właściwości fizykomechanicznych kompozytów w procesie degradacji. Próbki do badań otrzymano metodą liofilizacji. Proces degradacji badano poprzez pomiar ubytku masy, zmiany mikrostruktury, powierzchni właściwej, gęstości i wytrzymałości na ściskanie w czasie. Pomiary prowadzono po 3, 6 i 12 tygodniach inkubacji w soli fizjologicznej buforowanej fosforanem (PBS). Wyniki badań wykazały, że proces degradacji badanych kompozytów jest bardzo wolny, a dodatek zsyntezowanego HA nieznacznie go przyspiesza. Ubytek masy kompozytu po 12 tygodniach inkubacji w PBS wynosił zaledwie 0,47%. Procesowi degradacji towarzyszy spadek gęstości i wzrost powierzchni właściwej materiału w czasie. Porównanie wytrzymałości opracowanych kompozytów PCL/HA przed i po 12 tygodniach inkubacji w PBS, pozwala wnioskować, że dodatek zsyntezowanego hydroksyapatytu wpływa na wzrost wytrzymałości kompozytów w czasie (nawet do 20%).
EN
Polycaprolactone-based composites with filler in the form of hydroxyapatite fibers are one of the potential materials for tissue engineering applications. These materials are characterized not only by adequate porosity and mechanical strength, but also by bioactivity, biocompatibility and bioresorbability. From the point of view of the applicability of a given material, it is extremely important to control the degradation process of the composite over time, so that the scaffold can provide mechanical stability until the defect is restored. The paper presents the results of the study of the effect of the degradation process on the physicomechanical properties of the developed porous composites based on polycaprolactone (PCL) with the addition of synthesized hydroxyapatite (HA) fibers of different morphologies. In the study, special attention was paid to the effect of the synthesized powder on the change of physicomechanical properties of the composites during the degradation process. Samples for the study were obtained by freeze-drying method. The degradation process was studied by measuring weight loss, changes in microstructure, specific surface area, density and compressive strength over time. Measurements were conducted after 3, 6 and 12 weeks of incubation in PBS (phosphate-buffered saline). The results showed that the addition of synthesized HA slightly accelerates the degradation process of PCL/HA composites. Nevertheless, the degradation process is very slow. The weight loss of the composite after 12 weeks of incubation in PBS was only 0.47%. The degradation process is accompanied by a decrease in density and an increase in the specific surface area of the material over time. A comparison of the strength of the developed PCL/HA composites before and after 12 weeks of incubation in PBS, allows us to conclude that the addition of synthesized hydroxyapatite affects the increase in the strength of the composites over time (up to 20%).
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A hydroxyapatite (HA) based biocompatible and bioactive composite is an appropriate choice for bio-implants. This experimental work presents the influence of ZnO and Fe3O4 on the microstructure of HA-ZnO-Fe3O4 composites synthesized by the wet powder metallurgy process. These composites were characterized using SEM, energy-dispersive X-ray spectroscopy (EDS), and XRD. The obtained results showed the effect of the addition of Fe3O4 on the interface formation, which is exhibited by interconnected pores and sintered neck in the micrographs. The observed porosity helps to enhance the required osseointegration for the fixation of implants with human bones.
Functional and composite materials obtained from hydroxyapatite (HAp) are widely used in practice, which results in intensive research of systems containing hydroxyapatite. Doping with divalent ions of hydroxyapatite changes its properties, thus extending its application in material science. Substitution of calcium ions in the surface layer of hydroxyapatite by metal cations is used in the development of new catalysts, sorbents, sensors and materials for other applications. The doping of the surface of the hydroxyapatite with divalent ions may occur as a result of adsorption of metal cations on the surface groups and calcium exchange in the crystal structure of the hydroxyapatite. The paper presents the mechanisms of adsorption of selected bivalent ions Ba2+, Cd2+, Co2+, Fe2+, Sr2+, Zn2+ on hydroxyapatite. The influence of cation adsorption on unit cell parameters, crystallite size and particle size distribution is discussed.
Materiały na bazie polilaktydu są perspektywicznymi surowcami do wytwarzania substytutów kości. Stale poszukuje się nowych rozwiązań poprawiających ich właściwości mechaniczne. Obiecującym kierunkiem jest wprowadzenie bioaktywnej ceramiki, która nie tylko wpłynie na poprawę właściwości, lecz również na biokompatybilność materiału.
XX
The polylactide-based materials are prospective raw materials for the production of bone substitutes. New solutions to improve their mechanical properties are constantly being sought. A promising direction is the implementation bioactive ceramics, which will not only improve properties, but also could improve the biocompatibility of the material.
Purpose: Human bone suffered some degeneration due to age and accidents; therefore, there are many interests in the prepared synthetic bone with properties nearer to natural bone. The present study prepared a nanocomposite of polypropylene reinforced with different weight fraction of Nano hydroxyapatite (HAp) to be used as a bone replacement with good biological properties that enhanced the growth of osteoplastic cells and enhance the prevention of clots and coagulates creation. Design/methodology/approach: Nanocomposite from polypropylene reinforced with different weight fraction of Hydroxyapatite (HAp) (1,2 and 3) % prepared by first dispersion Nano hydroxyapatite insolvent and then mixing with a pellet of polypropylene by the twin-screw extrusion process, the current research study the surface properties ( atomic force microscopy (AFM), contact angle test) Moreover, it studied the characteristics of prepared nanocomposite materials (Differential Scanning Calorimetry (DSC), Field Emission-Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared (FTIR)). Findings: The AFM results show the surface roughness decreased with increasing content of HAp, which diminished the chance of creation clots and coagulates on it. The contact angle results referred to polypropylene behaviour transformed from hydrophobic to hydrophilic with addition HAp that permission to grow the osteoplastic cell on it, so the healing process is accelerated. Moreover, the FE-SEM images revealed uniform distribution and good bonding between polypropylene and Hydroxyapatite. The thermal properties were measured by the DSC test showed the melting temperature, and the enthalpy of melting (indicated to increase the crystalline structure per cent) are increased with increasing the percentage of Hydroxyapatite. Research limitations/implications: This research studied the characteristics of nanocomposite materials prepared by three steps (dispersion by ultrasonic device, manually mixed and melting and mixing by twin extruder) which can be used as a bone replacement. However, the main limitation was the uniform distribution of nano-hydroxyapatite within the matrix. In a further study, the cytotoxic test can be tested to study the effect of prepared nanocomposite on living cells’ growth. Practical implications: The interest object is how to connect among different properties to prepared bone replacement with good properties and biocompatibility that made able to stimulate the growth and healing process. Originality/value: The nano-hydroxyapatite is a biomaterial that has a composition similar to the natural mineral phase of the bone and does not have any negative effect, which enhanced the growth of osteoplastic cells and decreased the clots and coagulates creation; therefore, nano-hydroxyapatite is used to decrease the surface roughness which decreased the chance of coagulation creation and to enhance the hydrophilic properties.
The paper is focused on the preparation and characterization of calcium sulfate gypsum-based materials modified with hydroxyapatite of natural origin. To search for new bioactive materials, calcium sulfate gypsum Stodent III Arti was mixed with hydroxyapatite obtained in the three-step preparation process including hydrolysis, pre-calcination, and calcination of bones. Such-obtained material was characterized by X-ray diffractometry and Fouriertransform infrared spectroscopy. Additionally, the microstructure and chemical composition of the prepared composite materials were investigated with a scanning electron microscope equipped with an energy dispersive spectrometer detector. Moreover, the influence of the hydroxyapatite content in the materials on their in vitro degradation in storage solutions including artificial saliva, Ringer’s solution, and simulated body fluid was examined. A comparison of the degradation of gypsum composites demonstrated that in vitro stability is dependent on hydroxyapatite content. The samples' weight changes indicate hydroxyapatite addition results in increased degradation of prepared composite materials. Moreover, the imaging of the samples confirmed the formation of finely-crystalline apatite precipitate on the surface of the materials during immersion in incubation fluids.
PL
W pracy przedstawiono charakterystykę materiałów na bazie gipsu modyfikowanych hydroksyapatytem pochodzenia naturalnego. Hydroksyapatyt uzyskano w trzyetapowym procesie obejmującym hydrolizę, prekalcynację i kalcynację kości. Otrzymane materiały scharakteryzowano metodą dyfraktometrii rentgenowskiej i spektroskopii w podczerwieni z transformatą Fouriera. Dodatkowo zbadano mikrostrukturę i skład chemiczny wytworzonych materiałów kompozytowych za pomocą skaningowego mikroskopu elektronowego wyposażonego w rentgenowski spektrometr z dyspersją energii. Ponadto zbadano wpływ zawartości hydroksyapatytu w materiałach na ich degradację in vitro w płynach symulujących środowisko organizmu, takich jak sztuczna ślina, roztwór Ringera i symulowany płyn ustrojowy SBF. Porównanie degradacji kompozytów wykazało, że stabilność in vitro jest zależna od zawartości hydroksyapatytu. Analiza zmiany masy próbek w czasie inkubacji wskazała, że dodatek hydroksyapatytu powoduje zwiększoną degradację przygotowanych materiałów kompozytowych. Ponadto obrazowanie próbek potwierdziło powstawanie drobnokrystalicznego apatytu na powierzchni materiałów podczas inkubacji w płynach symulujących środowisko organizmu.
Bioceramic materials, such as hydroxyapatite (HAp), are characterized by high biocompatibility in the presence of tissues and body fluids without causing toxic or allergic reactions. Hydroxyapatite, due to its similarity to structures found in bones, is used both in the form of powders, e.g. as additives to bone cements, and implants coatings. However, this material is not characterized by antimicrobial properties, therefore attempts are made to improve its properties by introducing additional elements into the hydroxyapatite structure. Thanks to HAp’s high ion-exchange ability, silver can be introduced into its structure. The calcium ions present in the HAp structure can be easily replaced by silver ions to create a material endowed with high biocompatibility and antibacterial properties. The presented study is based on the analysis of the morphology of the modified powders via scanning electron microscopy (SEM), their chemical composition via X-ray energy dispersive spectroscopy (EDS) and chemical structure via X-ray diffraction (XRD) and Raman spectroscopy. The powders obtained through the ion exchange were mixtures of silver phosphates Ag3PO4 and HAp. The highest silver content was found in the sample modified with a 1M concentration of AgNO3 in the aqueous solution. It was also determined that the annealing of the obtained powders under vacuum at 800°C resulted in the formation of metallic silver and a change in the structure of HAp to β-TCP.
Polymer coatings are increasingly used in varied fields and applications from simple coatings of barrier to intricated nanotechnology based composite. In the present study, polyvinylidene fluoride(PVDF)/Hydroxyapatite (HA )coatings were produced by spin coating technique over 316L SS. Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) were used to observe the coated 316L SS substrates surface morphology. The corrosion protection efficiency of pure polyvinylidene fluoride and polyvinylidene fluoride/HA nanocomposite coatings on 316L SS was inspected using potentiodynamic polarization along with the ions release techniques in Hank’s solution. A superior biocompatibility and an improved protection performance against corrosion were obtained for the 316L SS samples with nanocomposite coatings compared with the pure polyvinylidene fluoride coatings and pristine 316L SS counterparts. The 316L SS samples coated by PVDF/HA nanocomposite showed enhanced corrosion protection within Hank’s solution. The corrosion of 316L SS samples within Hank’s solution increased from 92.99% to 99.99% when using 3wt% HA due to increasing the PVDF inhibition efficiency. Good agreements in the electrochemical corrosion parameters were obtained from using ions release and potentiodynamic polarization tests.
W artykule przedstawiono metodę oraz wyniki badań obejmujące próbę dostosowania przyrostowej technologii selektywnego łączenia ziaren proszku do wytwarzania indywidualizowanych ceramicznych uzupełnień ubytków kostnych z zastosowaniem syntetycznego hydroksyapatytu. W dobie intensywnego rozwoju nowoczesnych technologii wytwórczych pojawia się coraz więcej możliwości ich wykorzystania w medycynie, szczególnie z uwagi na zapewnienie precyzyjnego odwzorowania anatomii pacjenta, opartego na danych pochodzących z obrazowania medycznego. Przyrostowe wytwarzanie znalazło już zastosowanie w wytwarzaniu trójwymiarowych modeli fizycznych umożliwiających szczegółową analizę skomplikowanych przypadków oraz służących do planowania i symulacji operacji w celu zmniejszenia ryzyka oraz skrócenia czasu trwania zabiegu. Znane są również przypadki przeprowadzenia implantacji z wykorzystaniem indywidualizowanych implantów. Najczęściej wykorzystywanym materiałem w takich przypadkach są stopy tytanu, co niesie liczne ograniczenia: brak dopasowania własności mechanicznych, brak degradacji czy niepożądane reakcje obronne organizmu. Z tego powodu nieustannie trwają badania nakierowane na wytwarzanie bioakceptowalnych i biodegradowalnych materiałów, które posłużą wytwarzaniu czasowych konstrukcji wspomagających odbudowę naturalnej tkanki w miejscach ubytków. W artykule zaprezentowano metodę wytwarzania oraz przygotowania wszczepów z zastosowaniem biomateriału ceramicznego. W ramach prowadzonych badań wykonano analizę oraz dobrano odpowiednie materiały, parametry procesowe i przeanalizowano ich wpływ na jakość wytwarzanych modeli. Otrzymany w przygotowanej metodzie materiał do zastosowań medycznych poddano testom in vitro, w celu weryfikacji właściwości biologicznych.
EN
The paper presents the method and results comprising adjustment of the incremental technology of selective connection of the powder particles. It is used for the manufacturing of ceramic restorations of individualized bone defects based on synthetic hydroxyapatite. In the era of intensive development of modern technologies of manufacturing, there are more and more opportunities to use their extensive capabilities in medicine, particular by the precise mapping of the patient’s anatomy based on data from medical imaging. Incremental manufacturing has already found application in the manufacture of three-dimensional physical models enabling a detailed analysis of complicated cases and used for planning and simulation of operations to reduce the risk and duration of treatment. There are also known some cases of carrying out the implantation with the use of individualized implants. The most commonly used material in such cases are titanium alloys which cause many restrictions i.e., no matching of mechanical properties, lack of degradation or adverse reactions of the body’s defenses. For this reason, many research is being continuously conducted focusing on manufacturing bioacceptable and biodegradable materials, which will be used in manufacture of temporary structures supporting the restoration of the natural tissue in places of cavities. This paper presents a method of manufacturing and preparing implants using ceramic biomaterial. In this study, appropriate materials as well as process parameters have been chosen and their impact on the quality of the generated models was analyzed. Obtained material for medical use has been tested in vitro to verify biological properties.
A comparison of poly(l-lactide) (PLLA) and poly(l-lactide)/hydroxyapatite (PLLA/HAp) biocomposite microspheres fabricated by emulsion solvent evaporation technique designed for laser sintering (LS) applications is presented. Key properties such as thermal and structural as well as geometry, size distribution and powder flowability, which are crucial for this technique, are characterized to validate the applicability of microspheres for LS. The biocomposite microspheres turns out to be more suitable for the LS process than PLLA due to the higher thermal stability, broader sintering window and higher powder flowability.
PL
Porównano właściwości mikrosfer z poli(l-laktydu) (PLLA) i z biokompozytu poli(l-laktyd)/ hydroksyapatyt (PLLA/HAp), przygotowanych metodą emulsyjną z odparowaniem rozpuszczalnika, przeznaczonych do procesu spiekania laserowego (LS). W celu weryfikacji przydatności mikrosfer do LS scharakteryzowano kluczowe dla tej techniki właściwości: termiczne i strukturalne oraz geometrię, rozkład wymiarów i sypkość proszku. Wykazano, iż mikrosfery biokompozytowe wykazują lepsze właściwości predestynujące je do przetwarzania metodą LS niż mikrosfery PLLA, w tym większą stabilność termiczną, szersze okno parametrów spiekania i większą sypkość proszku.
Metalic materials intended for bone implants should exhibit not only appropriate mechanical properties, but also high biocompatibility. The surface treatment modifications, for example acidic treatment, laser treatment, ion implantation and deposition of highly biocompatible coatings, are practiced. One of the most popular methods of surface modification is to deposit hydroxyapatite (HAp) coatings. HAp naturally occurs in human body, but can be also synthesized in laboratory conditions. Among diverse deposition techniques, electrophoretic deposition (EDP) is a cost-effective method in which charged particles, dispersed in an organic medium, after applying voltage migrate to the counter charged electrode forming a thin coating. There are several parameters that can be controlled during the process and that directly affect the morphology of the surface. The zeta potential and pH of prepared colloidal suspension are closely related to suspension stability and affect the susceptibility for agglomeration of the particles. Electrical settings, especially applied voltage, affect primarily the mass of deposition, but also the porosity of the coating, as well as its homogeneity. One of the basic parameters of EDP method is time of process. With increasing process time, the thickness of the deposited coating increases. Importantly, its mechanical properties also decrease. Moreover, the particles shape and size also affect the morphology of the deposited coating. The analysis of many variables is necessary to choose the right parameters to obtain the coating with desired morphology. In this paper, the influence of each parameter on the morphology of hydroxyapatite coatings is discussed.
PL
W artykule omówiono parametry procesu osadzania elektroforetycznego (EDP) ze szczególnym uwzględnieniem wykorzystania tej metody do osadzania powłok hydroksyapatytowych (HAp) na metalicznych implantach kostnych. Bazując na obszernym przeglądzie najnowszej literatury, przedstawiono wpływ każdego z parametrów na strukturę powstającej powłoki.