BIOACTIVE COATING ON TITANIUM IMPLANT AND METHOD FOR MAKING THEREOF Russian patent published in 2010 - IPC A61L27/54 A61F2/02 A61C8/00 

FIELD: medicine.

SUBSTANCE: invention concerns medicine, more specifically the method for surfacing titanium implants that allows forming a bioactive surface. There is described a bioactive coating on the titanium implant exhibiting high adhesion to the implant surface and an extended rough surface sufficient for successful osteointegration of bone tissue and the method for making thereof. The bioactive coating on the titanium implant contains calcium-phosphate compounds and has multilevel porous structure with a rough surface. The coating has thickness 10-40 microns, total porosity 35-45% with average pore dimension 3-8 mcm, roughness 2.5-5 microns, adhesive strength 30-35 MPa. The coating contains calcium-phosphates in roentgenoamorphous condition. There is described method for making the bioactive coating on the titanium implant that involves surfacing by micro-arc oxide coating, but preceded with mechanical and chemical processing of the surface of the titanium implant that is followed with micro-arc oxide coating to make a multilevel porous structure of the calcium-phosphate coating. The mechanical and chemical processing represents sandblasting of the surface of the titanium implant to be exposed to chemical etching. For sandblasting, powdered aluminium oxide AI₂O₃ or silica SiO₂ of fraction 250-380 mcm is used to ensure roughness 1.5-5 mcm. Chemical etching is carried out by staining the surface of the titanium implant in an acid etchant heated to boiling temperature and prepared of hydrochloric and sulphuric acids of the composition as follows: 10 portions of HC1 (30%) and 80 portions of H₂SO₄ (60%)) and 10 portions of H₂O to form pores 1-2 mcm. Micro-arc oxide coating is performed in an anode mode with the following parametres: voltage 250-300 V, pulse duration 50-100 mcs, and pulse repetition rate - 50-100 Hz, within 3-10 minutes in an aqueous solution of electrolyte of orthophosphoric acid, hydroxyapatite and calcium carbonate, of the following composition, wt %: H₃PO₄ - 20, Ca₁₀(PO₄)₆(OH)₂ - 6, CaCO₃ - 9. The implant is made of titanium nanostructure with the average grain-subgrain size 60-110 mcm.

EFFECT: implant for bone tissue improves biological compatibility with a living organism.

13 cl, 3 dwg, 3 tbl, 1 ex