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The influence of autologous and heterologous extract of antimicrobial peptides on leukocytes isolated during titanium implant insertion in rabbit and ovine model

Zdziennicka Joanna, Szponder Tomasz, Latalski Michał, Żylińska Beata, Sobczyńska-Rak Aleksandra, Wessely-Szponder Joanna

Engineering of Biomaterials

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2021

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Vol. 24, no. 159

24--30

EN

This study evaluated the in vitro leukocyte response to titanium implants in the presence of autologous or heterologous antimicrobial peptides extracts. Antimicrobial peptides (AMPs) appeared to be a new approach both against microorganisms and for regulation of inflammatory and repair processes. To evaluate their potential usefulness in regenerative medicine, we prepared different extracts of neutrophil-derived AMPs from rabbit, ovine or porcine blood which contained AMPs of different compositions, mainly defensins, cathelicidins and fragments thereof. Then, we assessed in vitro the influence of different AMPs extracts on the neutrophils and monocyte-derived macrophages (MDM) activity. For this purpose, these cells were obtained from experimental animals, rabbits, or sheep submitted to insertion of a titanium implant into the tibial defect. The cultured cells stimulation was autologous or heterologous, dependently on the AMPs extract origin and the experimental animal species. The neutrophil activity was assessed on the basis of the enzymes release from azurophilic and secondary granules and the free radicals generation. The MDM functional assessment was based on the NO and superoxide generation and arginase activity. Additionally, morphological changes were evaluated in the cell cultures. Our results indicated that the origin of AMPs extract is crucial for its activity. The autologous extracts stimulated anti-inflammatory responses, whereas the heterologous extracts displayed pro-inflammatory effect on neutrophils and macrophages. These results might be considered during the introduction of new preparations in regenerative medicine.

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Fabrication and characterization of Zr microplasma sprayed coatings for medical applications

Voinarovych Sergii G., Alontseva Darya L., Kyslytsia Oleksandr N., Kaliuzhnyi Sergii, Khozhanov Alexandr R., Krasavin Alexander, Kolesnikova Tatiana

Advances in Materials Science

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2021

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Vol. 21, nr 2(68)

93--105

EN

This paper presents new results of studying the influence of parameters of microplasma spraying (MPS) of Zr wire on the structure of Zr coatings. The coating experiments were accomplished in a two level fractional factorial design. Individual particles of sprayed Zr wire and their splats on the substrate were collected under various spraying parameters (amperage, spraying distance, plasma gas flow rate and wire flow rate) and evaluated by Scanning Electron Microscopy (SEM) to establish the effect of particle size and shape on the coating microstructure. The particles were characterized by measurement of their sizes and the obtained results were evaluated in terms of their degree of melting. This was compared with the experimentally observed coating microstructure type and finally correlated to the investigated coating porosity to select the specific MPS parameters of Zr coatings depositing onto medical implants from Ti alloy. It was found that the main parameters influencing the size of the sprayed Zr particles and the porosity of the Zr coatings are the plasma gas flow rate and amperage. It was demonstrated that it is possible to control the porosity of Zr microplasma coatings in the range from 2.8% to 20.3% by changing the parameters of the MPS. The parameters of microplasma spraying of Zr wire were established to obtain medical implant coatings with porosity up to 20.3% and pore size up to 300 μm.

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Electrochemical Behavior of Titanium Implants in Artificial Saliva After Laser Surface Treatment

Biedunkiewicz A., Dembowska E., Figiel P., Biedunkiewicz W.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 1

91--97

EN

Peri-implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant connective tissue and progressive loss of supporting bone. In the treatment of peri-implantitis, a laser surgical technique is used. Lasers are a safe and gentle alternative to traditional dental tools. They allow oral surgeons and dentists to accomplish more complex tasks, reduce blood loss, decrease post-operative discomfort, reduce the chance of wound infection, achieve better wound healing and perform some procedures in close methods without access flap. The aim of the work was to determine the impact of laser surface treatment of titanium dental implants on its electrochemical behavior in artificial saliva at 37°C. The study used an Er, Cr: YSGG laser and diode lasers 810 nm and 980 nm for debridement of titanium implant surface. In the research, the thread on the surface of implant was scanned with the diode laser beam of energy 1, 1.25, 1.5 and 2 W, cw and Er, Cr YSGG: 1,5 and 2 W, pulse 30 Hz.

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Wpływ modyfikacji warstwy pasywnej implantów tytanowych na ich odporność korozyjną

Nawrat G., Simka W., Nieużyła Ł., Zdziech I.

Przemysł Chemiczny

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2006

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T. 85, nr 8-9

1204-1207

PL

Przedstawiono badania wpływu modyfikacji warstwy pasywnej na odporność korozyjną implantów tytanowych. Na podstawie badań elektrochemicznych określono wpływ procesu polerowania elektrolitycznego i warunków pasywacji na potencjał korozyjny, opór polaryzacyjny oraz prąd korozyjny i liniową szybkość korozji. Wyznaczono optymalne warunki prowadzenia procesu pasywacji dla próbek poddanych procesowi polerowania elektrolitycznego (średnia chropowatość Ra poniżej 0,16 µm).

EN

Tech.-grade Ti and Ti6A14V alloy (cf.. ISO 5832-3) wires were electrolytically polished and anodically passivated 10 min. at 20–60 V, 25–50°C, in the presence of Si, Nb, Ta or Zr anions. The elements were incorporated into the passive layer. Tyrode’s soln. tests showed both Ti and the alloy to have corrosion potentials shifted from –344 to –76 mV and from – 409 to –88 mV, resp. At higher temp. (50°C) and higher passivation voltages, the effect was greater: polarization resistance rose to a few MΩcm2, the linear corrosion rate and current d fell. For Ti, 60°C was the best passivation temp.

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Extra-cellular matrices for titanium implants

Douglas T., Hempel U., Bierbaum S., Scharnweber D., Worch H.

Inżynieria Biomateriałów

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2005

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R. 8, nr 47-53

12--13