Phosphate materials

T. Kanazawa, ed.. Inorganic Phosphate Materials, Kodansha, Tokyo, Japan, 1989. 

Therapeutic dental materials. Calcium phosphate materials. Dental implants. 

Other Ceramic Calcium Phosphate Materials. Other ceramic calcium phosphate materials for repairing bony defect iaclude p-tricalcium phosphate (P-TCP) [7758-87-4], P-Ca2(PO, and biphasic calcium phosphate (BCP) ceramics which consist of both P-TCP and HA. Unlike ceramic HA, P-TCP resorbs ia the tissue (293). The in vivo dissolution of BCP ceramic implants was shown (296) to iacrease with increasing P-TCP/HA ratio ia the implants. Both P-TCP and BCP can lead to new bone growth to various extents depending on the appHcations and the type of materials used (293,296). 

Kiln inclination varies wtih processes from 2 to 6 cm/m. Speed of rotation also varies from veiy slow, i.e., a peripheral speed of 0.15 iti/s for a TiOg pigment kiln, or 0.22 iti/s for a cement lain, to 0.64 iti/s for a unit calcining phosphate materials. 

Molecular phosphonate cages with metal, P, and O atoms as model compounds and a source for phosphate materials 99ACR117. 

The following examples describing the thermolytic behavior of di(ferf-butyl)phosphate complexes serve to demonstrate the utihty of the TMP approach for synthesis of various phosphate materials. 

There are several reasons why these cements are bland. Acid irritation is probably minimal. Poly(acrylic acid) is a weak add and, in addition, because of its high molecular weight will not readily diffuse along dentinal tubules and is also immobilized by phosphatic material in these tubules. Moreover, once set these cements rapidly become neutral. 

Zinc phosphates and phosphonates can form highly interesting coordination networks, some in the presence of additional ligands. A number of compounds that have useful properties for the formation of zinc phosphate materials will also be discussed. 

A zinc phosphate material formed in the presence of traro-l,2-diaminocyclohexane forms with pores of 24-membered rings and a consequent large amount of free space in the structure, Zn3(P04)2(P03OH)(diaminocyclohexane)-2H20. The tubular channels formed... 

Marchand, R. L Haridon, P. Feldmann, W. Proc. Third. Int. Symp. Inorganic Phosphate Materials, Lille (France), 1999. 

Our researchers have worked very hard to accomplish our goals by doing things we felt would enhance our synthetic bone materials and their performance to enable them to equal and often exceed the performance of autograft as implants as well as in other types of bone augmentation and replacement. The nonporous tooth enamel solid calcium phosphate materials have flexural strengths of over 20,000 lb in.2 However, without pores it would take an extremely long time to resorb this nonporous bioceramic. 

Phosphate materials that may be analyzed are bone, dentine, enamel, fish scales and invertebrate shells. In contrast to bone and dentine, enamel is extremely dense, so it is least likely to be affected diageneticaUy and the prime candidate for paleoeviromnental reconstractions. Biogenic apatites contain besides the PO4 group CO3 that substitutes for PO " and OH as well as labile CO3 (Kohn and Cerling 2002), the latter is removed by pretreatment with a weak acid. The... 

The bone tissue grows into the pore structure of the phosphate material, which, in its turn, slowly dissolves. At the same time mineralised bone is formed. 

Chart 15. Preparation of Phosphate Materials from Molecular Complexes... 

Waiawalkar. M, G. Roesky, H. W., Murugavel. R. Molecular phosphonate cages Model compounds and starting materials for phosphate materials, Acc. Chem. Res. 1999. 32, n 7-126,... 

Most of the insoluble or slightly soluble phosphate materials are used because they are less expensive than soluble phosphates or because they supply other elements. These products are rarely agronomical ly superior to soluble phosphates. However, some of them are valued for specialty uses because they may be safely placed in contact with seeds or roots in some situations. Slightly soluble phosphates are found to be useful in tropical agriculture where conditions are quite different from those in temperate zones. 

Spotts, E. and D. J. Dollhopf. 1992. Evaluation of phosphate materials for control of acid production in pyritic mine overburden. J. Environ. Qual. 21 627-634. 

---