Silicon-substituted apatites and process for the preparation thereof
US6312468A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 1999 |
| Grant date | Nov 6, 2001 |
| Priority date | — |
| Expiry date | Aug 9, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F2310/00293
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The present invention provides a synthetic silicon-substituted apatite or hydroxyapatite which comprises 0.1% to 5% by weight of silicon. The silicon-substituted apatite or hydroxyapatite may be used as a synthetic bone material for use in bone substitution, implants, fillers and cements, coatings for metallic implants, and for making hydroxyapatite-polymer composites. The silicon-substituted apatite is prepared by reacting a calcium salt or calcium hydroxide with orthophosphoric acid or a salt of orthophosphoric acid in the presence of a silicon-containing compound, the molar ratio of calcium ions to phosphorous-containing ions being from 1:0.5 to 1:0.7 and the molar ratio of calcium ions to silicon-containing ions being at least 1:0.2, whereby a precipitate of a silicon-substituted apatite is formed. On heating and/or sintering the silicon-substituted apatite at a temperature of from 500.degree. C. to 1400.degree. C. part or substantially all of the silicon-substituted apatite transforms to silicon-substituted hydroxyapatite.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.