Other

J.m. Huber Corporation

Ceramedical, Inc.

Sung-Tsuen Liu

Harvey H Chung

Gary M Freeman

William C Fultz

Patrick D McGill

Mark E Wozniak

Michel J Martin

Jason T Zapf

Michael Robert Hart

A method for forming calcium carbonate is provided, the method comprising the steps of: (a) milling calcium hydroxide; (b) providing a reactor vessel containing a slurry of the milled calcium hydroxide; and (c) carbonating the slurry of the milled calcium hydroxide by introducing carbon dioxide into the reactor vessel to form basic calcium carbonate by a precipitation reaction, wherein the initial reaction temperature is from about 8&#xb0; C. to about 15&#xb0; C.

Precipitated calcium carbonate

A new and useful method of simultaneously producing and granulating anhydrous dicalcium phosphate is provided. Such a method entails the reaction of concentrated phosphoric acid with a powdered material of lime and/or calcium carbonate in substantially equal stoichiometric amounts, with subsequent, mixing, drying, milling, and sieving to provide the correct target particle size range for the resultant granulated materials. Such specifically produced granulated anhydrous dicalcium phosphate materials exhibit very high available calcium levels, excellent flow characteristics, and very high capability for compression into tablets. Products including such particularly produced granulated anhydrous dicalcium phosphate materials are also encompassed within this invention.

Method of producing granulated anhydrous dicalcium phosphate

A new and useful method of simultaneously producing and granulating composite materials for simultaneous internal delivery of high amounts of calcium and phosphate to a subject (person or animal) is provided. Such a method entails the dropwise addition of concentrated phosphoric acid within a specified amount of water into a vessel containing a powdered material of lime and/or calcium carbonate, with the lime and/or calcium carbonate present in an excessive amount of the phosphoric acid, with subsequent, mixing, drying, milling, and sieving to provide the correct target particle size range for the resultant granulated materials. Such specifically produced granulated calcium carbonate/dicalcium phosphate materials exhibit very high available calcium levels, very high available phosphate levels, excellent flow characteristics, and very high capability for compression into tablets. Products including such particularly produced composite materials are also encompassed within this invention.

Method of producing granulated calcium carbonate/calcium phosphate composite materials with very high calcium to phosphate mole ratios

Disclosed is a composite material comprising a boehmite substrate coated with a precipitated silica, the composite having a BET specific surface area of from 1 m/g to 50 m/g, such that the composite material has a % silica coating parameter value of about 5% to about 50%. Also disclosed is a dentifrice comprising this composite material. When included in a dentifrice composition, the composite material not only provides excellent abrasive and cleaning performance but also has compatibility with other ingredients used in dentifrice formulations, such as fluoride, flavors and cationic species.

Silica-coated boehmite composites suitable for dentifrices

An abrasive precipitated calcium carbonate is provided that provides excellent cleaning properties without being excessively abrasive or damaging to gums or tooth surfaces. The abrasive, precipitated calcium carbonate has a primary particle size of about 1 &#x3bc;m to about 4 &#x3bc;m, and an aggregate size of about 3 &#x3bc;m to about 10 &#x3bc;m. Also disclosed is a method for forming calcium carbonate comprising the steps of: providing a reaction medium; introducing carbon dioxide and the calcium hydroxide slurry simultaneously into a reaction medium to form calcium carbonate while maintaining constant pH during calcium carbonate precipitation; and optionally drying the calcium carbonate slurry to form a dried calcium carbonate product. Also disclosed is a dentifrice containing the aforementioned abrasive, precipitated calcium, and one or more ingredients selected from the group consisting of humectants, thickening agents, binders, gums, stabilizing agents, antibacterial agents, fluorides, sweeteners, and surfactants.

A strong, thin flexible mineralized collagen membrane is disclosed that is useful for such medical applications as a barrier for guided tissue regeneration, periodontal defect repair, bone grafts and skin wound repair. The mineralized collagen membrane comprises a substantially homogeneous mineralized collagen composite consisting essentially of about 30% to about 70% by weight of a collagen component and about 30% to about 70% by weight of a calcium phosphate minerals component precipitated from a collagen slurry by a soluble calcium ion-containing solution and a soluble phosphate ion-containing solution. The calcium phosphate minerals component has a mole ratio of calcium to phosphate in the range of about 1.0 to about 2.0. The thin mineralized collagen membrane has a bulk density of the membrane of at least about 1.0 g/cm and has a thickness not greater than about 0.5 mm and preferably not greater than about 0.3 mm. A corresponding method of making the mineralized collagen membrane includes casting washed mineralized collagen slurry as a thin, flat sheet onto a surface, such as a sieve or filter paper, air drying the sheet and removing it from the surface as the thin mineralized collagen membrane.

Thin mineralized collagen membrane and method of making same

A coating composition for paper or paperboard products comprising a structured pigment. The structured pigment includes a plurality of chemically treated mineral particles. The mineral particles have a Malvern median particle size of about 0.3 microns to about 3.5 microns. The Malvern median particle size of the treated particles is less than 20% greater than the Malvern median particle size of the mineral particles prior to treatment.

Paper or paper board coating composition containing a structured clay pigment

A thin, strong, flexible mineralized collagen membrane is disclosed that is useful for such medical applications as a barrier for guided tissue regeneration, periodontal defect repair, bone grafts and skin wound repair. The mineralized collagen membrane comprises a substantially homogeneous mineralized collagen composite consisting essentially of about 30% to about 70% by weight of a collagen component and about 30% to about 70% by weight of a calcium phosphate minerals component precipitated from a collagen slurry by a soluble calcium ion-containing solution and a soluble phosphate ion-containing solution. The calcium phosphate minerals component has a mole ratio of calcium to phosphate in the range of about 1.0 to about 2.0. The thin, strong, flexible mineralized collagen membrane has a bulk density of at least about 1.0 g/cm,. A corresponding method of making the thin, strong, flexible mineralized collagen membrane is disclosed, including the steps of casting the washed mineralized collagen slurry into a thin sheet on a filtering media, air drying the thin sheet of mineralized collagen slurry and removing the dried sheet from the filtering media as a thin, strong, flexible mineralized collagen membrane.

Mineralized collagen membrane and method of making same

A method of preparing a polymer structured pigment slurry which comprises providing an anionic, aqueous slurry including a plurality of solid mineral particles, adding a low molecular weight, cationic polymer in an amount of less than about 0.20% by weight to the slurry and then adding a small amount of an inorganic dispersant to the polymer treated pigment slurry. The Malvern median particle size of the mineral particles treated with the polycationic polymer is less than about 20% larger than the Malvern median particle size of the untreated mineral particles.

Polymer structured clay pigment and method of preparing the same

This invention provides new inorganic composite materials for hard tissue replacement. The new composite material comprises solid material of calcium sulfate which is fully or partially converted to calcium phosphate from aqueous solution. This composite material has good biocompatibility and controllable resorption, and will be very useful for bone substitute material in orthopaedic and dental applications. The fully converted material which comprises mainly apatite calcium phosphate is also useful for chromatography application. A process to prepare these new composite materials is also described.

Calcium phosphate calcium sulfate composite implant material

Hard tissue replacement materials and methods for making same are disclosed. In one embodiment, the present composition comprises a synthetically derived, substantially homogenous composite containing collagen component and calcium phosphate-containing component precipitated from a liquid medium in which the collagen component is contained.

Composite materials for hard tissue replacement

A new surgical cement is disclosed. This surgical cement comprises a hardened cement formed from a mixture comprising a cementing component selected from the group consisting of calcium components having a solubility in water at 25.degree. C. in the range of about 0.5 .times. 10.sup.-2 M to about 20 .times. 10.sup.-2 M and mixtures thereof; a setting component selected from the group consisting of water soluble salts of polyfunctional carboxylic acids containing 2 to about 10 carbon atoms, water soluble dibasic phosphate salts and mixtures thereof; and water in an amount effective to form a paste from the mixture which paste hardens into said hardened cement which is biocompatible.

Resorbable surgical cements

A surgical cement of high biocompatibility, useful in orthopedic, maxillofacial and dental applications, comprising a calcium alkali phosphate cement with relatively high surface pH of about 7 or higher, and having a wide variety of chemical compositions, permitting flexibility in controlling the bioresorption rate by changing the chemical composition of the cementing powder.

Resorbable bioactive phosphate containing cements

New surgical cements for use in medical applications such as orthopedic and maxillofacial surgeries and dental applications are disclosed. These surgical cements comprise a hardened cement formed from a mixture comprising a cementing component selected from the group consisting of ceramics having the formula

Phosphate-containing surgical cements

This invention provides a calcium phosphate cement with relatively high surface pH which is very beneficial from the biocompatibility point of view. When calcium phosphate salts react with an acidic reagent to form cement, it normally involves the dissolution and recrystallization process. The acidity of the setting cements depends strongly on the nature of the calcium phosphate salt used, the acidity of the setting reagent, and the reaction rate. The present invention uses high alkaline calcium phosphate ceramics such as tetracalcium phosphate alone or together with calcium phosphate ceramics such as .alpha.-tricalcium phosphate as base cementing powder to increase the surface pH of the setting cement.

Growing community of inventors

Aberdeen, MD, United States of America

Sung-Tsuen Liu