169 results about "Calcium phosphate cement" patented technology

A system is provided for the storage, preparation and administration of calcium phosphate cements. The subject invention provides a storage means for storing a two component calcium phosphate cement having a liquid component and a dry component. Also provided is a preparation means for combining the two components of the cement while present in the storage means. The subject invention further provides a means for administering the prepared cement to a physiological site. The subject devices and methods find use in a variety of applications where the introduction of a flowable material capable of setting to a solid calcium phosphate mineral to a physiological site is desired, including dental and orthopedic applications.

The invention describes a new calcium phosphate cement powder, whose composition can best be described over the Ca/P molar ratio range of 1.35 to 1.40, most preferably 1.39, and whose two components were prepared by wet chemical synthesis procedures. One component is chemically-synthesized, bi-phasic alpha-TCP (Ca₃(PO₄)₂, 95 wt %)+HA (Ca₁₀(PO₄)₆(OH)₂, 5 wt %) powder, while the second component is again a chemically-synthesized, single-phase DCPD (CaHPO₄·2H₂O) powder. A setting solution (Na₂HPO₄·2H₂O) is used to form a self-setting calcium phosphate cement from the powder mixture. This cement can be used as bone filler or bone substitute in applications, which require higher rates of resorption.

This invention relates to novel calcium phosphate-coated implantable medical devices and processes of making same. The calcium-phosphate coatings are designed to minimize the immune response to the implant (e.g. restenosis in stenting procedures) and can be used to store and release a medicinally active agent in a controlled manner. Such coatings can be applied to any implantable medical devices and are useful for a number of medical procedures including (but not limited to) balloon angioplasty in cardiovascular stenting, ureteral stenting and catheterisation. The calcium phosphate coatings can be applied to a substrate as one or more coatings by a sol-gel deposition process, an aerosol-gel deposition process, a biomimetic deposition process, a calcium phosphate cement deposition process, an electro-phoretic deposition process or an electrochemical deposition process. The coating can contain and elude a drug in an engineered manner.

The present invention provides a novel process for producing a calcium phosphate cement or filler which hardens in a temperature dependent fashion in association with an endothermic reaction. In the reaction a limited amount of water is mixed with dry calcium phosphate precursors to produce a hydrated precursor paste. Hardening of the paste occurs rapidly at body temperature and is accompanied by the conversion of one or more of the reactants to poorly crystalline apatitic calcium phosphate. The hardened cements, fillers, growth matrices, orthopedic and delivery devices of the invention are rapidly resorbable and stimulate hard tissue growth and healing. A composite material is provided including a strongly bioresorbable, poorly crystalline apatitic calcium phosphate composite and a supplementary material. The supplementary material is in intimate contact with the hydroxyapatite material in an amount effective to impart a selected characteristic to the composite. The supplemental material may be biocompatible, bioresorbable or non-resorbable. A method for treating a bone defect also is provided by identifying a bone site suitable for receiving an implant, and introducing a strongly resorbable, poorly crystalline apatitic calcium phosphate at the implant site, whereby bone is formed at the implant site. The implant site may be a variety of sites, such as a tooth socket, non-union bone, bone prosthesis, an osteoporotic bone, an intervertebral space, an alveolar ridge or a bone fracture.

The present invention discloses a method for making a porous calcium phosphate article including i) preparing a shaped article from a paste containing a calcium phosphate cement, a pore-forming powder and a setting liquid; ii) immersing the shaped article in an immersing liquid for a period of time so that the pore-forming powder is dissolved in the immersing liquid, creating pores in said shaped article; and iii) removing the resulting porous shaped article from the immersing liquid, wherein the resulting porous shaped article has an improved compressive strength. The porous shaped calcium phosphate article of the present invention may be used as a tissue-engineered scaffold, medical implant or a reinforcing constituent of a composite.

The present invention discloses a method for making a porous calcium phosphate article including i) preparing a shaped article from a paste containing a calcium phosphate cement, a pore-forming powder and a setting liquid; ii) immersing the shaped article in an immersing liquid for a period of time so that the pore-forming powder is dissolved in the immersing liquid, creating pores in said shaped article; and iii) removing the resulting porous shaped article from the immersing liquid, wherein the resulting porous shaped article has an improved compressive strength. The porous shaped calcium phosphate article of the present invention may be used as a tissue-engineered scaffold, medical implant or a reinforcing constituent of a composite.

The invention concerns injectable bone filling cements, in particular hydraulic calcium phosphate cements, the latter being prepared from at least two initial liquid or pasty constituents comprising each a species reactive in solution or in suspension, the solidification process being initiated when said constituents are being mixed.

A bone or dental implant material in the form of a paste includes a mixture of calcium phosphate and/or calcium-containing powders and a solution that is (1) an acidic calcium phosphate solution saturated with respect to one or more calcium phosphate compounds, (2) a concentrated acid solution, or (3) salt solutions with a cationic component other than calcium. The paste is stable, resistant to washout and will form hydroxyapatite and harden relatively rapidly to a cement.

The present invention discloses a method for making a porous calcium phosphate article including i) preparing a shaped article from a paste containing a calcium phosphate cement, a pore-forming powder and a setting liquid; ii) immersing the shaped article in an immersing liquid for a period of time so that the pore-forming powder is dissolved in the immersing liquid, creating pores in said shaped article; and iii) removing the resulting porous shaped article from the immersing liquid, wherein the resulting porous shaped article has an improved compressive strength. The porous shaped calcium phosphate article of the present invention may be used as a tissue-engineered scaffold, medical implant or a reinforcing constituent of a composite.

The invention relates to a magnesium phosphate cement based rapid repair mortar and a preparation method thereof. The rapid repair mortar includes the following components by weight: 100 parts of magnesium phosphate cement, 6-50 parts of a mineral admixture, 50-300 parts of fine aggregate, and 10-30 parts of water. The magnesium phosphate cement is obtained by mixing of, by weight, 60-70 parts of metal oxide powder, 20-28 parts of phosphate, 3-6 parts of a retarder and 4-6 parts of a coagulation regulating component. The magnesium phosphate cement based rapid repair mortar is prepared by adopting magnesium phosphate cement as the cementing material, adopting dipotassium phosphate for coagulation regulating modification, and using sand as the fine aggregate, then adding a proper amount of mineral admixture, and performing mixing with water. Compared with the prior art, the magnesium phosphate cement based rapid repair mortar provided by the invention has the advantages of controllable coagulation time, high bonding strength, good stability and high water resistance, etc.

In some embodiments, an implant may include a porous component and a load bearing component at least partially surrounding the porous component. The porous component has a porosity that is greater than the porosity of the load bearing component. One or more protrusions may be present on the load bearing component. The porous component and/or a load bearing component may be at least partially composed of calcium phosphate.

The invention discloses a making method of composite tissue engineering rack of original poring self-solidifying calcium phosphate, which comprises the following steps: placing porous rack of calcium phosphate cement into drier to dry; immersing porous rack into macromolecular solution; extracting into vacuum for 0.5-6h; injecting macromolecular material into the pore of porous rack of calcium phosphate cement; drying the surface of porous rack through filter paper; pre-freezing under -60- -4 deg.c for 1-48h; drying the frozen material to do multiple injections until the pore is filled with cement; obtaining the product.

The present invention discloses a method for making a porous calcium phosphate article including i) preparing a shaped article from a paste containing a calcium phosphate cement, a pore-forming powder and a setting liquid; ii) immersing the shaped article in an immersing liquid for a period of time so that the pore-forming powder is dissolved in the immersing liquid, creating pores in said shaped article; and iii) removing the resulting porous shaped article from the immersing liquid, wherein the resulting porous shaped article has an improved compressive strength. The porous shaped calcium phosphate article of the present invention may be used as a tissue-engineered scaffold, medical implant or a reinforcing constituent of a composite.

The present invention discloses a method for making a porous calcium phosphate article including i) preparing a shaped article from a paste containing a calcium phosphate cement, a pore-forming powder and a setting liquid; ii) immersing the shaped article in an immersing liquid for a period of time so that the pore-forming powder is dissolved in the immersing liquid, creating pores in said shaped article; and iii) removing the resulting porous shaped article from the immersing liquid, wherein the resulting porous shaped article has an improved compressive strength. The porous shaped calcium phosphate article of the present invention may be used as a tissue-engineered scaffold, medical implant or a reinforcing constituent of a composite.

The present invention provides a novel process for producing a calcium phosphate cement or filler which hardens in a temperature dependent fashion in association with an endothermic reaction. In the reaction a limited amount of water is mixed with dry calcium phosphate precursors to produce a hydrated precursor paste. Hardening of the paste occurs rapidly at body temperature an is accompanied by the conversion of one or more of the reactants to poorly crystalline apatitic calcium phosphate. The hardened cements, fillers, growth matrices, orthopedic and delivery devices of the invention are rapidly resorbable and stimulate hard tissue growth and healing.

Methods and devices are provided for delivery an orthopedic, e.g., calcium phosphate cement to a target bone site. In practicing the subject methods, a flowable cement composition is delivered to a target bone site in conjunction with vibration. Also provided are the devices that deliver a flowable cement to a target bone site according to the subject methods. Introducing a flowable cement to a target bone site in conjunction with vibration in accordance with the subject methods provides for highly controlled penetration of the delivered cement throughout the target bone site without the use of substantial pressure. The subject devices and methods find use in a variety of different applications, and are particularly suited for use in applications where a calcium phosphate cement is to be delivered to cancellous tissue, e.g., as found in a vertebral body.

The invention refers to an injectable composition for a bone mineral substitute material, which comprises a dry powder mixed with an aqueous liquid. The powder comprises a first reaction component comprising a calcium sulphate hemihydrate with the capability of being hardened to calcium sulphate dihydrate when reacting with said aqueous liquid; a second reaction component, which comprise a calcium phosphate with the capability of being hardened to a calcium phosphate cement when reacting with said aqueous liquid; and at least one accelerator for the reaction of said first and/or second reaction component with said aqueous liquid. A method of producing an injectable bone mineral substitute material is also provided, wherein the composition is mixed in a closed mixing and delivery system for delivery.

A method for increasing working time/setting time of monolithic tetracalcium phosphate (TTCP) cement paste formed by mixing a TTCP powder with an aqueous solution, which includes heating the TTCP powder, prior to the mixing, so that the TTCP powder is maintained at a temperature of 50-350° C. for a period of time which is greater than one minute, and that a TTCP cement paste formed by mixing the resulting heated TTCP powder with the aqueous solution has a prolonged working time in comparison with that formed by mixing TTCP powder that has not been subjected to such heating with the aqueous solution.

The present invention discloses a prosthetic bone implant made of a hardened calcium phosphate cement having an apatitic phase as a major phase, which includes a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth.

The present invention discloses a prosthetic bone implant made of a hardened calcium phosphate cement having an apatitic phase as a major phase, which includes a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth.

The present invention discloses a prosthetic bone implant made of a hardened calcium phosphate cement having an apatitic phase as a major phase, which includes a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth.

A composite calcium phosphate cement for preparing artificial bone is prepared through immersing carbon fibres in NaOH solution, heating at 70-90 deg.C for 2-3 hr, flushing, drying, shearing short, proportionally mixing it with calcium phosphate cement, stirring to obtain composite powder, proportionally mixing it with solidifying liquid, stirring, moulding and curing.

A self-foaming bone cement is described herein. In one variation, the bone cements include a self setting calcium phosphate cement formulation which when cured, forms macroscopic pores of varying sizes and densities with sufficient surface area to provide substantial regions for bone turnover.

The present invention discloses a prosthetic bone implant made of a hardened calcium phosphate cement having an apatitic phase as a major phase, which includes a dense cortical portion bearing the majority of load and a porous cancellous portion allowing a rapid blood/body fluid penetration and tissue ingrowth.