Preparation, solubility, and cytocompatibility of zinc-releasing calcium phosphate ceramics

✍ Scribed by Ito, Atsuo ;Ojima, Kenji ;Naito, Hiroshi ;Ichinose, Noboru ;Tateishi, Tetsuya

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 291 KB
• Volume: 50
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/(sici)1097-4636(200005)50:2<178::aid-jbm12>3.0.co;2-5

✦ Synopsis

Zinc is an essential trace element with stimulatory effects on bone formation. Therefore, zinc was doped into ␤-tricalcium phosphate to develop zinc-releasing biomaterials to promote bone formation. The zinc-doped ␤-tricalcium phosphate, ␤-tricalcium phosphate, and hydroxyapatite powders were mixed at a (Ca+Zn)/P molar ratio of 1.60, followed by sintering into a dense body at 1100°C for 1 h. The sintered body was a composite ceramic consisting of zinc-doped ␤-tricalcium phosphate and hydroxyapatite phases. The composite ceramic contained zinc oxide when the zinc content was higher than 1.20 wt %. The composite ceramic released zinc under pseudophysiological conditions. However, the release of calcium and phosphate de-creased with an increase in zinc content in a range higher than 0.12 wt % owing to a decrease in solubility of the zincdoped ␤-tricalcium phosphate phase. Proliferation of osteoblastic MC3T3-E1 cells was significantly increased on the composite ceramic with a zinc content from 0.6 to 1.20 wt %, compared with those without zinc. When the zinc content was higher than 1.20 wt %, release of zinc from the zinc oxide caused cytotoxicity. Therefore, the zinc content of the composite ceramic must be <1.20 wt %.