Crystalline hydroxyapatite coatings synthesized under hydrothermal conditions on modified titanium substrates

Bioceramic Coatings for Metallic Implants

“…Silicon-substituted HA is now successfully used as bone graft material in spinal fusion, but it is not a good alternative for the hard tissue, due to its low hydrophobicity, which decreases the 2 1.67 [12][13][14][15][16][17][18][19] Calcium-deficient hydroxyapatite Ca 10Àx (HPO 4 ) x (PO 4 ) 6Àx (OH) 2Àx, with 0 < x_1 1.50 < Ca/ P < 1.67 [20][21][22][23][24] Carbonate hydroxyapatite [37] adsorption of proteins onto a material's surfaces, and its mechanical and tribological characteristics. Some researchers have also proposed the incorporation of Mg in the HA lattice, in order to accelerate the osseointegration process of implants.…”

Synthesis of the hydroxyapatite coatings on the Ti substrates by mechanical alloying

“…The HA coating provides bioactivity, corrosion resistance, and biocompatibility, whereas biocompatible metals provide mechanical strength [7]. The structural similarity of Ca 10 (PO 4 ) 6 (OH) 2 (hydroxyapatite) to hard tissues makes HA an attractive coating material to accelerate bone growth around the implant.…”

“…Moreover, as a ceramic coating, HA provides protection against corrosion and metal debris release, resulting in the reduction of implant rejection [7].…”

HA coating fabricated by electrochemical deposition on modified Ti6Al4V alloy

“…However, the bioactivity of titanium alloy is poor [2]. Hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 , HA) has excellent biocompatibility and has been recognized as osteoconductive [3,4]. Natural hydroxyapatite represents about 70% of the natural human bones.…”

“…However, the mechanical strength of HA is too poor to be used in load-bearing applications. Therefore, HA coatings on bio-inert metallic prostheses have been extensively investigated in order to obtain medical implants combining the chemical and biological properties of hydroxyapatite with the mechanical properties of titanium alloy [5][6][7]. Several methods have been reported to fabricate HA coating on implant surfaces, such as plasma spraying [8][9][10][11][12], sputtering process [13,14], pulsed laser deposition [15], sol-gel [16], electrophoretic method [17], electrochemical deposition [18][19][20][21][22][23][24], etc.…”