In Vitro Properties of Manganese-Substituted Tricalcium Phosphate Coatings for Titanium Biomedical Implants Deposited by Arc Plasma

Abstract

Bioactive manganese (Mn)-doped ceramic coatings for intraosseous titanium (Ti) implants are developed. Arc plasma deposition procedure is used for coatings preparation. X-ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy, and Electron Paramagnetic Resonance (EPR) methods are applied for coatings characterization. The coatings are homogeneous, composed of the main phase α-tricalcium phosphate (α-TCP) (about 67%) and the minor phase hydroxyapatite (about 33%), and the Mn content is 2.3 wt%. EPR spectroscopy demonstrates that the Mn ions are incorporated in the TCP structure and are present in the coating in Mn2+ and Mn3+ oxidation states, being aggregated in clusters. The wetting contact angle of the deposited coatings is suitable for cells’ adhesion and proliferation. In vitro soaking in physiological solution for 90 days leads to a drastic change in phase composition; the transformation into calcium carbonate and octacalcium phosphate takes place, and no more Mn is present. The absence of antibacterial activity against Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa bacteria strains is observed. A study of the metabolic activity of mouse fibroblasts of the NCTC L929 cell line on the coatings using the MTT (dye compound 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test demonstrates that there is no toxic effect on the cell culture. Moreover, the coating material supports the adhesion and proliferation of the cells. A good adhesion, spreading, and proliferative activity of the human tooth postnatal dental pulp stem cells (DPSC) is demonstrated. The developed coatings are promising for implant application in orthopedics and dentistry.

Effect of Temperature on Electrochemically Assisted Deposition and Bioactivity of CaP Coatings on CpTi Grade 4

“…So far, thin CaP coatings have been obtained using various methods, including pulsed laser deposition, ion beam techniques, sputter deposition, electrochemically assisted deposition (ECAD), electrospraying, electrophoretic deposition, biomimetic deposition in simulated body fluid (SBF), and sol–gel method [ 19 ]. Recently, arc plasma has been applied to produce bioactive and non-toxic manganese-substituted α–TCP coatings on Ti [ 35 ]. These Mn–TCP coatings were composed of α-Ca 3 (PO 4 ) 2 (67%) and HA (33%).…”

“…The structure and surface morphology of the CaP coatings can be tailored through the selection of conditions of the ECAD process, including electrolyte composition, pH of the electrolyte, temperature, electrochemical conditions, and time of deposition [ 19 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ]. The ECAD method produces the CaP coatings in the amorphous state, and heat treatments at high temperatures are used to achieve high crystallization [ 38 ].…”

“…The ECAD process’s operating parameters primarily affect stoichiometry, the grade of crystallization, particle size, and microstructure of the obtained CaP coatings, and thus allow to shape their properties as thermal stability, mechanical performance, biocompatibility, and corrosion resistance [ 39 ]. The CaP coatings have been deposited so far from a nitrate bath without or with HCl’s addition, which caused the dissolution of individual components of the bath [ 19 , 32 , 33 , 34 , 35 , 36 , 38 , 40 ]. However, the obtained coatings were characterized by a heterogeneous structure.…”

Using DFT to Calculate the Parameters of the Crystal Field in Mn2+ Doped Hydroxyapatite Crystals

“…The crystal structure of HAp (Ca 10 (PO 4 ) 6 (OH) 2 ) allows for a wide range of substitutions, which can affect various material properties ranging from mechanical to antimicrobial [2][3][4]. Among various ions with therapeutic effects, manganese (Mn) has recently attracted attention for inclusion in diverse bioceramics [5][6][7][8][9]. Manganese is one of the essential trace elements for human health and one of the metals found in natural (bio)apatites.…”

Arc Plasma Deposition of TiO2 Nanoparticles from Colloidal Solution

“…Different surface modification technics, such as chemical etching and coating, ion implantation and deposition, anodic oxidation, etc., can be used for this purpose [7]. However, arc plasma deposition can be singled out as an easy-to-apply coating deposition technique that offers the possibility to deposit different types of coatings on the surface of the metallic implants depending on their medical application requirements [7,9,10].…”