Orthopedic implant having a crystalline calcium phosphate coating and methods for making the same

• Main Authors: Qu, Haibo, Kasinath, Rajendra, Ernsberger, Craig, Ginn, Steven N, Vass, Stephanie, Tong, Weidong
• Format: Patent
• Language: English
• Published: 13.07.2021
• Subjects: APPARATUS THEREFOR; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS, ORSURGICAL ARTICLES; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; DISINFECTION, STERILISATION, OR DEODORISATION OF AIR; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; HUMAN NECESSITIES; HYGIENE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS, OR SURGICALARTICLES; MEDICAL OR VETERINARY SCIENCE; METALLURGY; METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS INGENERAL; PERFORMING OPERATIONS; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS; SPRAYING OR ATOMISING IN GENERAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TRANSPORTING

An orthopedic implant having a metal surface and a calcium phosphate layer disposed on at least part of the metal surface is described. The calcium phosphate layer has an average crystallite size of less than about 100 nm in at least one direction and dissolves for more than 2 hours in vitro. The calcium phosphate layer is substantially free of carbonate. The coating, which is formed on a sodium titanate surface, has increased shear strength and tensile strength. The coating is formed by a solution deposited hydroxyapatite process under inert conditions. The pH of the solution varies by less than 0.1 pH unit/hour during coating formation.