4372 results about "Hydroxyapatites" patented technology

Blends of biodegradable polymers, preferably poly(caprolactone) and poly(D,L-lactic-co-glycolic) acid are discussed as well as their applications in the medical field, particularly with regard to bone tissue engineering. Preferably, hydroxyapatite ("HA") granules are incorporated into the blends and the resulting blends have desirable mechanical, physical, and biological characteristics. Even more preferably the compositions of the present invention are utilized to form osteoconductive composites that supported bone cell growth on the surface as well as throughout the scaffold.

An injectable and moldable putty comprising biodegradable calcium-based compounds including calcium sulfate, hydroxyapatite, and tricalcium phosphate is invented. The putty hardens into a solid body when mixed with water, saline, serum, or other neutral aqueous solutions. The hardening time of the putty can be tailored in order to meet the specific requirements of various dental or orthopedic applications. The pH of the putty is neutral during and after mixing. The invented putty may be used as bone graft, bone implant, or implantable drug delivery device.

An improved bone graft is provided for human implantation, bone graft includes a substrate block of high strength biocompatible material having a selected size and shape to fit the anatomical space, and a controlled porosity analogous to natural bone. The substrate block may be coated with a bio-active surface coating material such as hydroxyapatite or a calcium phosphate to promote bone ingrowth and enhanced bone fusion. Upon implantation, the bone graft provides a spacer element having a desired combination of mechanical strength together with osteoconductivity and osteoinductivity to promote bone ingrowth and fusion, as well as radiolucency for facilitated post-operative monitoring. The bone graft may additionally carry one or more natural or synthetic therapeutic agents for further promoting bone ingrowth and fusion.

The present invention provides a biocompatible coating comprising calcium phosphate that is functionally graded across the thickness of the coating. The coating, which preferably includes hydroxyapatite, is particularly useful for coating implants, such as dental or orthopedic implants. The functionally graded coating is generally crystalline near the interface with the surface of the implant, with crystallinity and crystal diameter decreasing toward the outer layer of the coating. The invention further provides methods for preparing a coated implant comprising a functionally graded calcium phosphate coating thereon.

Polymeric nanofibers have been developed which are useful in a variety of medical and other applications, such as filtration devices, medical prosthesis, scaffolds for tissue engineering, wound dressings, controlled drug delivery systems, cosmetic skin masks, and protective clothing. These can be formed of any of a variety of different polymers, either non-degradable or degradable. In a preferred embodiment demonstrated in the following examples, nanofibers are formed of biodegradable and non biodegradable polyphosphazenes, their blends with other polyphosphazenes or with organic, inorganic / organometallic polymers as well as composite nanofibers of polyphosphazenes with nanosized particles such as hydroxyapatites.

A dietary supplement for benefitting human bone health includes a calcium source, a source of vitamin D activity, and an osteoblast stimulant. A preferred calcium source is microcrystalline hydroxyapatite, which also contains protein (mostly collagen), phosphorus, fat, and other minerals. A preferred source of vitamin D activity is cholecalciferol, and a preferred osteoblast stimulant is ipriflavone. In addition to these basic ingredients, the composition can further include various other minerals known to occur in bone, vitamin C, and glucosamine sulfate, all of which exert beneficial effects on growth and maintenance of healthy bone. A method for benefitting human bone health involves administering a daily regimen of the dietary supplement.

The spinal cage comprises a structural component having sufficient strength to withstand the compressive loading between vertebral bodies. The structural component is integrated with an osteoconductive component to facilitate bone growth between the vertebral bodies. The structural component may comprise any of PEEK, PEKK, or other structural material. The osteoconductive component may comprise any of allograft, natural bone, tricalcium phosphate, hydroxyapatite or a blend of calcium carbonate, calcium lactate and other calcium salts. A method for making the spinal cage involves molding polymers around an osteoconductive component, heat staking, and may further include ultrasonically welding, snap fit or mechanically assembling and / or adhesively bonding components.

A method is provided for separating a protein from one or more other proteins using hydroxyapatite chromatography in which the protein does not bind to hydroxyapatite but the other protein(s) does. In some embodiments, a second protein affixed to a solid support has been used previously to purify the protein by affinity chromatography, and small amounts of the second protein are introduced in the sample during this process. The protein being purified can comprise at least one constant antibody immunoglobulin domain. The second protein can bind to proteins comprising such a domain.

An engineered regenerative biostructure (erb) for implantation into a human body as a bone substitute, which includes an internal microstructure, mesostructure and / or macrostructure to provide improved bone in-growth, and methods for making the erb. Under one aspect of the invention, the biostructure has resorbable and nonresorbable regions. Under another aspect of the invention, the biostructure is constructed of hydroxyapatite, tricalcium phosphate and / or demineralized bone. Under yet another aspect of the invention, the porous biostructure is partially or fully infused with a resorbable, nonresorbable or dissolvable material.

This invention relates to novel room-temperature process for obtaining calcium phosphate, in particular hydroxyapatite, coatings and microspheres that encapsulate drugs, proteins, genes, DNA for therapeutical use. The coatings and microspheres are designed to perform a defined biological function related to drug delivery, such as gene therapy through gene delivery. A novel method for encapsulation, and subsequent controlled release of therapeutically active agents from such biofunctional coatings and microspheres is disclosed. Such coatings and microspheres are useful for side-effects free, long-term, targeted, controlled release and delivery of drugs, proteins, DNA, and other therapeutic agents.

Two (or more), -component, body-implantable, absorbable, biocompatible, putty, and non-putty hemostatic tamponades for use in surgery. Component 1 is a finely powdered bulking material, preferably less than 50 microns, e.g. the calcium, magnesium, aluminum, or barium salts of saturated or unsaturated carboxylic acids containing about 6 to 22 carbon atoms, hydroxyapatite, DBM, polyglycolide, polylactide, poldioxinones, polycaprolactones, absorbable glasses, gelatin, collagens, mono, and polysaccharides starches. Component 2, a dispersing vehicle, may be esters of C8-C18 monohydric alcohols with C2-C6 aliphatic monocarboxylic acids; C2-C18 monohydric alcohols with polycarboxylic acids; C8-C30 monohydric alcohols; tocopherol and esters thereof with C2-C10 aliphatic monocarboxylic acids or polycarboxylic acids; absorbable 10-14C hydrocarbons; free carboxylic acids such as oleic, capric, and lauric; dialkyl ethers and ketones; alkyl aryl ethers and ketones, polyhydroxy compounds and esters and ethers thereof; (ethylene oxide / propylene oxide copolymers), oils e.g. olive oil, castor oil and triglycerides.

Described herein are methods and compositions comprising a mixture of silk polymer and hydroxyapatite. The methods described herein can be used to prepare a mixture of silk polymer and hydroxyapatite and further provide mixtures that can be molded into a desired shape. Also encompassed herein are compositions comprising a mixture of silk polymer and hydroxyapatite having a desired shape, which can further be implanted, for example, to facilitate bone healing or tooth structure or support. Such compositions can also include agents, such as therapeutic agents, or cells.

Nanotubular structured titanium (Ti) substrates have been coated with nanoparticulate hydroxyapatite (nano-HA). The nano-HA surface is highly adherent to the nanotubular Ti surface and is free of microparticles. The nano-HA coated nanotubular Ti surface promotes osteoblast cell adhesion and is particularly suitable for orthopedic and dental implants where deposition of osteoblasts and other proteins is important in bone formation.

Two (or more), -component, body-implantable, absorbable, biocompatible, putty, and non-putty hemostatic tamponades for use in surgery. Component 1 is a finely powdered bulking material, preferably less than 50 microns, e.g. the calcium, magnesium, aluminum, or barium salts of saturated or unsaturated carboxylic acids containing about 6 to 22 carbon atoms, hydroxyapatite, DBM, polyglycolide, polylactide, poldioxinones, polycaprolactones, absorbable glasses, gelatin, collagens, mono, and polysaccharides starches. Component 2, a dispersing vehicle, may be esters unsubstituted and N-substituted pyrrolidones of C8-C18 monohydric alcohols with C2-C6 aliphatic monocarboxylic acids; C2-C18 monohydric alcohols with polycarboxylic acids; C8-C30 monohydric alcohols; tocopherol and esters thereof with C2-C10 aliphatic monocarboxylic acids or polycarboxylic acids; absorbable 10-14C hydrocarbons; free carboxylic acids such as oleic, capric, and lauric; dialkyl ethers and ketones; alkyl aryl ethers and ketones, polyhydroxy compounds and esters and ethers thereof; (ethylene oxide / propylene oxide copolymers), oils e.g. olive oil, castor oil and triglycerides.

Embodiments of the present invention provide an osseointegrative implant and related tools, components and fabrication techniques for surgical bone fixation and dental restoration purposes. In one embodiment an all-ceramic single-stage threaded or press-fit implant is provided having finely detailed surface features formed by ceramic injection molding and / or spark plasma sintering of a powder compact or green body comprising finely powdered zirconia. In another embodiment a two-stage threaded implant is provided having an exterior shell or body formed substantially entirely of ceramic and / or CNT-reinforced ceramic composite material. The implant may include one or more frictionally anisotropic bone-engaging surfaces. In another embodiment a densely sintered ceramic implant is provided wherein, prior to sintering, the porous debound green body is exposed to ions and / or particles of silver, gold, titanium, zirconia, YSZ, α-tricalcium phosphate, hydroxyapatite, carbon, carbon nanotubes, and / or other particles which remain lodged in the implant surface after sintering. Optionally, at least the supragingival portions of an all-ceramic implant are configured to have high translucence in the visible light range. Optionally, at least the bone-engaging portions of an all-ceramic implant are coated with a fused layer of titanium oxide.

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.

a biocompatible and biodegradable implant for a cavity in a bone of a living organism is made of a biocompatible and biodegradable granules which are selected from the group including biopolymers, bioglasses, bioceramics preferably calcium sulfate, calcium phosphate such as monocalcium phosphate monohydrate, monocalcium phosphate anhydrous, dicalcium phosphate dihydrate, dicalcium phosphate anhydrous, tetracalcium phosphate, calcium orthophosphate phosphate, α-tricalcium phosphate, β-tricalcium phosphate, apatite such as hydroxyapatite, or a mixture thereof. The biocompatible and biodegradable granules are provided with a coating, which comprises at least one layer of a biocompatible and biodegradable polymer which is selected from the group including poly((α-hydroxyesters), poly(orthoesters), polyanhydrides, poly(phosphazenes), poly(propylene fumarate), poly(ester amides), poly(ethylene fumarate), polylactide, polyglycolide, polycaprolactone, poly(glycolide-co-trimethylene carbonate), polydioxanone, co-polymers thereof and blends of those polymers. The biocompatible and biodegradable implants are obtained by fusing together the polymer-coated granules through polymer-linkage of the polymer coatings of neighboring granules.

Ceramic materials operable to repair a defect in bone of a human or animal subject comprising a porous ceramic scaffold having a bioresorbable coating, and a carrier comprising denatured demineralized bone. The ceramic may contain a material selected from the group consisting of hydroxyapatite, tricalcium phosphate, calcium phosphates, calcium carbonates, calcium sulfates, and combinations thereof. The compositions may also contain a bone material selected from the group consisting of: bone powder, bone chips, bone shavings, and combinations thereof. The bioresorbable coating may be, for example, demineralized bone matrix, gelatin, collagen, hyaluronic acid, chitosan, polyglycolic acid, polylactic acid, polypropylenefumarate, polyethylene glycol, or mixtures thereof.

Polymeric nanofibers have been developed which are useful in a variety of medical and other applications, such as filtration devices, medical prosthesis, scaffolds for tissue engineering, wound dressings, controlled drug delivery systems, cosmetic skin masks, and protective clothing. These can be formed of any of a variety of different polymers, either non-degradable or degradable. In a preferred embodiment demonstrated in the following examples, nanofibers are formed of biodegradable and non biodegradable polyphosphazenes, their blends with other polyphosphazenes or with organic, inorganic / organometallic polymers as well as composite nanofibers of polyphosphazenes with nanosized particles such as hydroxyapatites.

The present invention is a bioactive endodontic material and its use for filling the tooth and bone cavities. The present invention, by using calcium salt, calcium oxide, calcium silicate, and calcium phosphate compounds as essential constituents, and mixing them with a water base solution, prepares a bioactive calcium and phosphate enriched material. The enriched material (cement) comprises high concentration of water-soluble calcium and phosphate, and immediately forms hydroxyapatite during and after setting. The cement is biocompatible, antibacterial, capable to form an effective seal against reentrance of microorganisms into the filled cavity, compatible to handle and set in an aqueous environment, and able to stimulate hard tissue healing.

The invention discloses a composite heavy metal polluted soil conditioner as well as application and an application method thereof. The soil conditioner comprises the following components: plant ash, calcium magnesium phosphate, quicklime, zeolite and organic fertilizers at a weight ratio of (0.3-1.1):(0.1-1.2):(0.4-2.1):(0.1-0.6):(0.008-0.06):(0.4-1.2). Through inorganic components such as quicklime, calcium magnesium phosphate and phosphate in hydroxyapatite as well as potassium carbonate in the plant ash, the soil conditioner can be used for fixing heavy metals in polluted soil and improving the fertility of the polluted soil in combination with organic manures such as the plant ash and the organic fertilizers so as to continuously intensify the restoration of the polluted soil, has the advantages of relatively-high stability, good environmental friendliness and low cost, can be used for inactivating and restoring various heavy metal polluted soil, especially has a good restoration effect on soil pollution caused by waste slag discharged by industrial and mining enterprises, can be used for realizing the treatment goal without generating secondary pollution, and is liable to realize large-area popularization.

The present invention provides machinable calcium phosphate bone substitute material implants having mechanical properties comparable to those of natural bone. The implants include intimately mixed solid precursor materials that react under physiological conditions to form poorly-crystalline hydroxyapatite and eventually are remodeled into bone in vivo. The implants can include a biocompatible polymer to increase density and strength and control resorbability.

Nano-particles of calcium and phosphorous compounds are made in a highly pure generally amorphous state by spray drying a weak acid solution of said compound and evaporating the liquid from the atomized spray in a heated colunm followed by collection of the precipitated particles. Hydroxyapatite (HA) particles formed by such apparatus and methods are examples of particle manufacture useful in bone and dental therapies. Dual nozzle spraying etechniques are utilized for generally insoluble compounds.

A hydraulic cement for biomedical applications. The cement sets in-situ, hardening when exposed to water to produce nano-dispersed composite of calcium-silicate-hydrate gel mixed with hydroxyapatite. In comparison with prior cements, the composition provides high biocompatibility, high bioactivity and high biomechanical strength, due to the composite structure of the calcium silicate hydrate reinforced with co-precipitated particles of hydroxyapatite. Biocompatibility is also increased due to an absence of aluminum and magnesium in the composition. The cement is suitable for variety of applications, including dental implants, bone fixation, and bone repair.

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 invention relates to the use of Fused Deposition Modeling to construct three-dimensional (3D) bioresorbable scaffolds from bioresorbable polymers such as polycaprolactone (PCL), or from composites of bioresorbable polymers and ceramics, such as polycaprolactone / hydroxyapatite (PCL / HA). Incorporation of a bioresorbable ceramic to produce a hybrid / composite material support provides the desired degradation and resorption kinetics. Such a composite material improves the biocompatibility and hard tissue integration and allows for increased initial flash spread of serum proteins. The basic resorption products of the composite also avoids the formation of an unfavorable environment for hard tissue cells due to a decreased pH. The scaffolds have applications in tissue engineering, e.g., in tissue engineering bone and cartilage.

A method of making artificial bone comprises providing a membrane of collagen with solutions of calcium ions and of phosphate ions on opposite sides of the membrane. The calcium ions and phosphate ions diffuse through the membrane and precipitate as a hydroxyapatite material. Control of ionic concentrations ensures that precipitation takes place within the fibrils of the membrane. The result is an artificial bone material comprising a matrix of collagen and a hydroxyapatite material deposited within the matrix.

An osteoinductive bone graft substitute composition that does not return to its original shape upon hydration or manipulation is disclosed, comprising, in combination, about 86-89% by weight of a calcium phosphate particulate mineral component and about 11-14% by weight of a purified fibrillar collagen, the mineral component including about 20% to about 60% by weight of hydroxyapatite and about 60% to about 20% by weight of tricalcium phosphate. A package configured to store a bone graft composition is disclosed, comprising an inner sterile polymeric V-shaped pouch located in an outer sterile polymeric V-shaped pouch. Methods for repairing a bone defect in a patient are disclosed using the osteoinductive bone graft substitute composition.