Abstract: Methods for producing a room temperature stable, phase pure .alpha.-C.sub.3 P product, and compositions derived therefrom, are provided. In the subject method, a tricalcium phosphate source is heated to a temperature sufficient to convert substantially all of said tricalcium phosphate source to a substantially phase pure .alpha.-C.sub.3 P product. The temperature of the resultant product is rapidly cooled to a temperature below about 700.degree. C., resulting in a room temperature stable, reactive .alpha.-C.sub.3 P product. The resultant .alpha.-C.sub.3 P product may be milled to provide an .alpha.-C.sub.3 P composition which may find use in the preparation of calcium phosphate cements.

Abstract: Methods for producing a room temperature stable, phase pure .alpha.-C.sub.3 P product, and compositions derived therefrom, are provided. In the subject method, a tricalcium phosphate source is heated to a temperature sufficient to convert substantially all of said tricalcium phosphate source to a substantially phase pure .alpha.-C.sub.3 P product. The temperature of the resultant product is rapidly cooled to a temperature below about 700.degree. C., resulting in a room temperature stable, reactive .alpha.-C.sub.3 P product. The resultant .alpha.-C.sub.3 P product may be milled to provide an .alpha.-C.sub.3 P composition which may find use in the preparation of calcium phosphate cements.

Abstract: Two component, storage stable apatitic cement compositions, as well as methods for their production, are provided. The dry component of subject apatitic cements comprises basic calcium source particles at least partially coated with a partially neutralized acidic calcium phosphate. The dry component of subject compositions is prepared by combining basic calcium source particles with dissolved acidic phosphate in at least a partially aqueous medium, whereby the basic calcium source particles become partially coated with a partially neutralized acidic calcium phosphate. The reaction is terminated prior to completion of the reaction between the acidic phosphate and the basic calcium source by removing the available water from the reaction mixture. In a first mode, the subject cement may be produced by mechanically mixing an acidic phosphate source with basic calcium source particles in the presence of an aqueous solvent and stopping the reaction between the acid and base prior to completion.

Abstract: Mineralized collagen is prepared by forming calcium phosphate mineral under mild agitation in situ in the presence of dispersed collagen fibrils. A stable composition is obtained with desirable physical characteristics mimicking the characteristics of bone.

Abstract: Setting times of calcium phosphate cement compositions are enhanced by the addition of phosphate or carbonate lubricant compositions. Methods for preparing the cement compositions are provided.

Abstract: Methods and compositions are provided for coating a substrate with a strongly adherent hydroxyapatite coating, which allows for ingrowth of natural bone and strong bonding between the coating and the substrate. The procedure provides for repetitive coatings at varying concentrations of coating forming reagents, where the highest concentration is used initially. The coating has particular application for prostheses, where porous areas of the prostheses are completely coated with a thin sturdy coating of hydroxyapatite.

Abstract: Mineralized collagen is prepared by forming calcium phosphate mineral under mild agitation in situ in the presence of dispersed collagen fibrils. A stable composition is obtained with desirable physical characteristics mimicking the characteristics of bone.

Abstract: Methods, compositions and apparatus are provided for coating a substrate with a strongly adherent hydroxyapatite coating, which allows for ingrowth of natural bone and strong bonding between the coating and the substrate. The procedure provides for coating under conditions which form sticky particles which bind to the substrate to form a crystalline hydroxyapatite coating. The coating has particular application for prostheses, where porous areas of the prostheses are completely coated with a thin sturdy coating of hydroxyapatite.The apparatus includes a coating trough in which the substrates are present and the reactive components added. The medium is recirculated in an outer circuit through a distribution tank solution preparation tank and coating trough. Means are provided for maintaining temperature and pH. The substrates are maintained in a line normal to the flow in the trough and can be rotated to ensure even coating.

Abstract: Novel compositions are provided for the production of hydroxyapatite, where a dry mixture is provided which combines a calcium source and an acidic phosphate source, particularly monocalcium phosphate monohydrate or orthophosphoric acid crystals. These two are combined, optionally with other ingredients, with mechanical mixing, resulting in partial reaction or intimate combination to produce a product which requires less water for formation of a desired viscosity, has enhanced mechanical properties and is physiologically acceptable.

Abstract: Methods and compositions are provided for coating a substrate with a strongly adherent hydroxyapatite coating, which allows for ingrowth of natural bone and strong bonding between the coating and the substrate. The procedure provides for repetitive coatings at varying concentrations of coating forming reagents, where the highest concentration is used initially. The coating has particular application for prostheses, where porous areas of the prostheses are completely coated with a thin sturdy coating of hydroxyapatite.

Abstract: Calcium phosphate minerals are formed by using phosphoric acid source substantially free of uncombined water in conjunction with a calcium source, normally as any combination of carbonate, phosphate and hydroxide, and, as required, any additional base to neutralize the phosphoric acid. Protein may be optionally added. The resulting product is readily formed and then sets to a hard, stable, workable shaped object.

Abstract: Novel compositions are provided for the production of hydroxyapatite, where a dry mixture is provided which combines a calcium source and an acidic phosphate source, particularly monocalcium phosphate monohydrate or orthophosphoric acid crystals. These two are combined, optionally with other ingredients, with mechanical mixing, resulting in partial reaction or intimate combination to produce a product which requires less water for formation of a desired viscosity, has enhanced mechanical properties and is physilogically acceptable.

Abstract: Calcium phosphate minerals are formed by using phosphoric acid substantially free of uncombined water in conjunction with a calcium source, normally as any combination of carbonate, phosphate and hydroxide, and, as required, any additional base to neutralize the phosphoric acid. Protein may be optionally added. The resulting product is readily formed and then sets to a hard, stable, workable shaped object.

Abstract: Octacalcium phosphate and hydroxyapatite are provided, where octacalcium phosphate is produced as novel single crystals and organized polycrystalline structures that are non-dense. The crystals serve as fibers, which find application in a wide variety of applications as well as coatings of prosthetic devices or other materials which may have physiological application.

Abstract: Calcium phosphate minerals are formed by using highly concentrated phosphoric acid in conjunction with a calcium source, normaly as carbonate or a combination of carbonate and hydroxide, optimally in conjunction with calcium phosphate crystals and additional base to neutralize the phosphoric acid. Protein may be optionally added. The resulting product is readily formed and then sets to a hard, stable, workable shaped object.