| Title | Liquid phase sintering of hydroxyapatite by phosphate and silicate glass additions: Structure and properties of the composites |
| Publication Type | Journal Article |
| 1995 |
| Authors | Santos, JD, Reis, RL, Monteiro, FJ, Knowles, JC, Hastings, GW |
| Journal | Journal of Materials Science: Materials in MedicineJ. MATER. SCI. MATER. MED. |
| Volume | 6 |
| Issue | 6London, United Kingdom |
| Pagination | 348 - 352 |
| Date Published | 1995/// |
| 09574530 (ISSN) |
| Adhesion, article, Bioactivity, Bioglass, Biomaterials, Bone, bone prosthesis, calcium phosphate, chemical binding, Chemical bonds, chemical composition, Chemical structure, Complex calcium phosphate silicate, Composite materials, crystal, density, Density measurement (specific gravity), glass, Human blood plasma, hydroxyapatite, Liquid phase sintering, Mechanical properties, Mechanics, phosphate, Phosphates, plasma, priority journal, Scanning electron microscopy, silicate, Silicates, Sintering, Structure (composition), surface property, thickness |
| Phosphate- and silicate-based glasses were added to hydroxyapatite in order to improve its mechanical properties and to fabricate composites with different degrees of bioactivity. A strong chemical bonding was obtained between hydroxyapatite and the phosphate-based glasses leading to samples approaching theoretical density, according to density measurements and scanning electron microscopy. Bioglass® additions led to the formation of a complex calcium phosphate silicate which hampered the reinforcement process. The fracture toughness of the hydroxyapatite-glass composites was shown to be within the 1.1-1.2 MPam(1/2) range, which is double that determined for sintered hydroxyapatite. A 2 μm thick apatite layer was observed on the surface of the hydroxyapatite-glass composites after 48 h immersion in a simulated human blood plasma, whereas only a few apatite crystals were detected on sintered hydroxyapatite after 7 days immersion. From the results obtained we anticipate that the composites might show a higher rate of bone bonding, leading to enhanced bioactivity.Phosphate- and silicate-based glasses were added to hydroxyapatite in order to improve its mechanical properties and to fabricate composites with different degrees of bioactivity. A strong chemical bonding was obtained between hydroxyapatite and the phosphate-based glasses leading to samples approaching theoretical density, according to density measurements and scanning electron microscopy. Bioglass
(R) additions led to the formation of a complex calcium phosphate silicate which hampered the reinforcement process. The fracture toughness of the hydroxyapatite-glass composites was shown to be within the 1.1-1.2 MPa m
1/2 range, which is double that determined for sintered hydroxyapatite. A 2 μm thick apatite layer was observed on the surface of the hydroxyapatite-glass composites after 48 h immersion in a simulated human blood plasma, whereas only a few apatite crystals were detected on sintered hydroxyapatite after 7 days immersion. From the results obtained we anticipate that the composites might show a higher rate of bone bonding, leading to enhanced bioactivity.
|
| http://www.scopus.com/inward/record.url?eid=2-s2.0-0029311049&partnerID=40&md5=433498e286bfad74a296d1fafc50c223 |
