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Microwave assistant synthesis of calcium phosphate minerals using hen’s eggshells as a calcium source

Kalbarczyk Marta, Szcześ Aleksandra

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 6

167--177

EN

In this study raw hen’s eggshells were used as a calcium source for calcium phosphate mineral synthesis. The materials composed of brushite and different amounts of HA (hydroxyapatite) and β-TCP (β-tricalcium phosphate) with the needle-like, sheet-like and hexagonal structures were synthesized in the presence of the microwave. It was found that the time of microwave action, temperature and initial pH are parameters affecting the morphology and composition of the obtained materials, i.e. the increasing duration of MW exposure increases the amount of HA increases, whereas the temperature increase causes an increase in the contents of brushite and β-TCP. The lowering of initial pH leads to an increase in the brushite content.

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Temperature behaviour of ceramic biocomposites investigated via hot-stage microscopy

Pawlik Justyna, Cholewa-Kowalska Katarzyna

Engineering of Biomaterials

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2019

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Vol. 22, no. 150

22--28

EN

In this study, sol-gel bioactive glasses and β-TCP composites were investigated regarding their thermal behaviour, microstructure, and phase composition. Sol-gel bioactive glasses based on the CaO-SiO2 -P2O5 system of either a high SiO2 content (S2) or a high CaO content (A2) were mixed with the β-TCP at 25:75, 50:50 and 75:25 weight ratios. Basing on the HSM results, i.e. shrinkage curves, densification intervals and characteristic temperatures, the sintering temperatures of composites were indicated. Scanning electron microscopy and X-ray diffraction were used to determine the microstructure and phase composition of composites after sintering at selected temperatures, i.e. 1100°C and 1200°C. The SEM/EDX investigations proved the well-sintered and densified microstructure of the sintered composites. The chemistry of sol-gel bioactive glasses influenced both the thermal beha-viour and the phase composition of the composites. The dominant phases for A2-β-TCP materials were α-TCP, pseudowollastonite and β-TCP, while for S2-β-TCP – cristobalite, β-TCP, and α-TCP. However, the content of each phase varied, depending on the A2 or S2 content in the composite composition. Hot-stage microscopy provides useful information for selecting optimal sintering temperature in order to obtain well-sintered and strengthened material. Moreover, by a carefully selected combination of sol-gel bioactive glasses and β-TCP it is possible to obtain the materials with favorable phase composition with regard to biological activity.

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In vitro and in vivo evaluation of novel Tadalafil/β-TCP/Collagen scaffold for bone regeneration: A rabbit critical-size calvarial defect study

Soufdoost Reza Sayyad, Yazdanian Mohsen, Tahmasebi Elaheh, Yazdanian Alireza, Tebyanian Hamid, Karami Ali, Nourani Mohammad Reza, Panahi Yunes

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 3

789--796

EN

Different composite materials have been investigated in bone regeneration but none of them have a significant regeneration in a short time. In this study, the novel scaffold with the osteoinductive characteristic in order to accelerate bone regeneration for 6 weeks. Tadalafil/β-TCP/Collagen (TβC) and β-TCP/Collagen (βC) composite scaffolds were prepared and analyzed by porosity, biodegradability and MTT tests. And then, three bone defects (8 mm diameter, n = 6 group) were produced and filled with TβC, βC scaffolds and the third defect was unfilled as a control. Samples were taken and evaluated by histological, radiological and histomorphometric evaluation at 4 and 6 weeks. In vitro tests showed that both scaffold approximately had the same results in the percentage of porosity and in vitro cytotoxicity. Biodegradability of the βC scaffold was more than TβC scaffold. In vivo test showed bone regeneration was more in TβC scaffold at 6 weeks based on radiological and histopathologic analysis compared with βC scaffold and control groups. Histomorphometric analysis showed that the amount of the bone regeneration was significant in TβC group in comparison βC and control groups (P < 0.05) at 6 weeks. This study highlights the promising application of TβC scaffold with Tadalafil for successful bone regeneration by enhancing osteogenesis.

4

Badanie możliwości przygotowania past do drukowania przestrzennego (3D) z wybranych biomateriałów ceramicznych

Wiśniewski Z., Jaegermann Z., Tymowicz-Grzyb P., Biernat M., Pęczkowski P.

Szkło i Ceramika

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2016

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R. 67, nr 4

10--15

PL

Celem niniejszej pracy było przygotowanie past do drukowania przestrzennego z wybranych biomateriałów oraz wykonanie próby wyciskania past przez ustnik o średnicy wewnętrznej 0,45 mm. W ramach pracy wytypowano proszki biomateriałów i przeprowadzono badanie ich uziarnienia i morfologii. Wykonano zestawy past o różnych zawartościach substancji uplastyczniających z czterech rodzajów biomateriałów stosowanych w chirurgii kości: z kalcytu, aragonitu, hydroksyapatytu i trójfosforanu wapnia – β-TCP. Z użyciem specjalistycznej przystawki do maszyny wytrzymałościowej testowano sposób wyciskania past z jednoczesnym pomiarem siły potrzebnej do formowania pasma. Ocenę jakości uzyskanych pasm (jednorodności masy, morfologii powierzchni pasma, zdolności do wzajemnego zespolenia pasm pomiędzy sobą oraz podatności na odkształcenie) prowadzono metodą obserwacji obrazów w mikroskopie stereoskopowym i skaningowym. Następnie wytypowano receptury past, które po dopracowaniu szczegółów technologicznych będą mogły być zastosowane w docelowym urządzeniu drukującym. Doświadczenia wynikłe z realizacji pracy będą wykorzystywane przy opracowaniu receptur past i formowaniu ceramicznych struktur przestrzennych w drukarkach 3D.

EN

The aim of this work was to prepare pastes for 3D printing made of selected biomaterials and to attempt an extrusion of pastes through the nozzle with an inside diameter of 0,45 mm. For the aim of the study powders of biomaterials were selected, their particle size was measured and powders’ morphology was observed. Pastes with different contents of plasticizing substances made of four types of biomaterials used in bone surgery: the calcite, aragonite, hydroxyapatite and tricalcium phosphate – β-TCP were prepared. The method of pastes extrusion process with simultaneous measurement of the force needed to form the bands was determined using a special adapter for testing machine. Evaluation of the quality of the bands (microstructure uniformity, surface morphology of bands, capacity to form a junction between bands and the deformability) was performed by observations in the stereomicroscope and scanning electron microscope. Then the most suitable pastes recipes were selected. Technological details of their preparation have to be optimized for their application in selected printing device. The experience resulting from this work will be used in designing ceramic pastes systems for application in 3D printers.